diff --git a/library/compiler-builtins/.github/workflows/main.yaml b/library/compiler-builtins/.github/workflows/main.yaml
index 2729b8fa5d5c3..2ded0f6177d7b 100644
--- a/library/compiler-builtins/.github/workflows/main.yaml
+++ b/library/compiler-builtins/.github/workflows/main.yaml
@@ -15,13 +15,19 @@ env:
   RUSTDOCFLAGS: -Dwarnings
   RUSTFLAGS: -Dwarnings
   RUST_BACKTRACE: full
-  BENCHMARK_RUSTC: nightly-2026-02-10 # Pin the toolchain for reproducable results
+  BENCHMARK_RUSTC: nightly-2026-08-05 # Pin the toolchain for reproducable results
+
+defaults:
+  run:
+    # Add `-ux` to the default template specified at
+    # https://docs.github.com/en/actions/reference/workflows-and-actions/workflow-syntax#defaultsrunshell
+    shell: bash --noprofile --norc -euxo pipefail {0}
 
 jobs:
   # Determine which tests should be run based on changed files.
   calculate_vars:
     name: Calculate workflow variables
-    runs-on: ubuntu-24.04
+    runs-on: ubuntu-26.04
     timeout-minutes: 10
     env:
       GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
@@ -30,7 +36,7 @@ jobs:
       extensive_matrix: ${{ steps.script.outputs.extensive_matrix }}
       may_skip_libm_ci: ${{ steps.script.outputs.may_skip_libm_ci }}
     steps:
-      - uses: actions/checkout@de0fac2e4500dabe0009e67214ff5f5447ce83dd # v6.0.2
+      - uses: actions/checkout@3d3c42e5aac5ba805825da76410c181273ba90b1 # v7.0.1
         with:
           persist-credentials: false
           fetch-depth: 500
@@ -53,61 +59,63 @@ jobs:
       matrix:
         include:
         - target: aarch64-apple-darwin
-          os: macos-15
+          os: macos-26
         - target: aarch64-unknown-linux-gnu
-          os: ubuntu-24.04-arm
+          os: ubuntu-26.04-arm
         - target: aarch64-pc-windows-msvc
-          os: windows-11-arm
+          os: windows-11-vs2026-arm
         - target: arm-unknown-linux-gnueabi
-          os: ubuntu-24.04
+          os: ubuntu-26.04
         - target: arm-unknown-linux-gnueabihf
-          os: ubuntu-24.04
+          os: ubuntu-26.04
         - target: armv7-unknown-linux-gnueabihf
-          os: ubuntu-24.04
+          os: ubuntu-26.04
         - target: i586-unknown-linux-gnu
-          os: ubuntu-24.04
+          os: ubuntu-26.04
         - target: i686-unknown-linux-gnu
-          os: ubuntu-24.04
+          os: ubuntu-26.04
         - target: loongarch64-unknown-linux-gnu
-          os: ubuntu-24.04
+          os: ubuntu-26.04
         - target: powerpc-unknown-linux-gnu
-          os: ubuntu-24.04
+          os: ubuntu-26.04
         - target: powerpc64-unknown-linux-gnu
-          os: ubuntu-24.04
+          os: ubuntu-26.04
+        - target: powerpc64-unknown-linux-musl
+          os: ["self-hosted", "linux", "powerpc64", "musl"]
         - target: powerpc64le-unknown-linux-gnu
-          os: ubuntu-24.04
+          os: ubuntu-26.04
         - target: powerpc64le-unknown-linux-gnu
           os: ubuntu-24.04-ppc64le
         # FIXME(ci): re-enable these once more capacity is avialable
         # - target: riscv64gc-unknown-linux-gnu
         #   os: ["self-hosted", "linux", "riscv64"]
         - target: riscv64gc-unknown-linux-gnu
-          os: ubuntu-24.04
+          os: ubuntu-26.04
         - target: s390x-unknown-linux-gnu
           os: ubuntu-24.04-s390x
         - target: thumbv6m-none-eabi
-          os: ubuntu-24.04
+          os: ubuntu-26.04
         - target: thumbv7em-none-eabi
-          os: ubuntu-24.04
+          os: ubuntu-26.04
         - target: thumbv7em-none-eabihf
-          os: ubuntu-24.04
+          os: ubuntu-26.04
         - target: thumbv7m-none-eabi
-          os: ubuntu-24.04
+          os: ubuntu-26.04
         - target: wasm32-unknown-unknown
-          os: ubuntu-24.04
+          os: ubuntu-26.04
         - target: x86_64-unknown-linux-gnu
-          os: ubuntu-24.04
+          os: ubuntu-26.04
         - target: x86_64-apple-darwin
-          os: macos-15-intel
+          os: macos-26-intel
         - target: i686-pc-windows-msvc
-          os: windows-2025
+          os: windows-2025-vs2026
         - target: x86_64-pc-windows-msvc
-          os: windows-2025
+          os: windows-2025-vs2026
         - target: i686-pc-windows-gnu
-          os: windows-2025
+          os: windows-2025-vs2026
           channel: nightly-i686-gnu
         - target: x86_64-pc-windows-gnu
-          os: windows-2025
+          os: windows-2025-vs2026
           channel: nightly-x86_64-gnu
     runs-on: ${{ matrix.os }}
     needs: [calculate_vars]
@@ -116,12 +124,10 @@ jobs:
       JOB_TARGET: ${{ matrix.target }}
       JOB_CHANNEL: ${{ matrix.channel }}
       MAY_SKIP_LIBM_CI: ${{ needs.calculate_vars.outputs.may_skip_libm_ci }}
-      RUN_IN_DOCKER: ${{ matrix.os == 'ubuntu-24.04' }}
+      RUN_IN_DOCKER: ${{ matrix.os == 'ubuntu-26.04' }}
     steps:
     - name: Print runner information
-      shell: bash
       run: |
-        set -x
         uname -a
         lscpu || (sysctl -a | grep cpu) || true
         echo "home: ${HOME:-not found}"
@@ -129,13 +135,12 @@ jobs:
 
     # Native ppc and s390x runners don't have rustup by default
     - name: Install rustup
-      if: matrix.os == 'ubuntu-24.04-ppc64le' || matrix.os == 'ubuntu-24.04-s390x'
+      if: matrix.os == 'ubuntu-26.04-ppc64le' || matrix.os == 'ubuntu-26.04-s390x'
       run: sudo apt-get update && sudo apt-get install -y rustup
 
-    - uses: actions/checkout@de0fac2e4500dabe0009e67214ff5f5447ce83dd # v6.0.2
+    - uses: actions/checkout@3d3c42e5aac5ba805825da76410c181273ba90b1 # v7.0.1
       with: { persist-credentials: false }
     - name: Install Rust (rustup)
-      shell: bash
       run: |
         channel="nightly"
         # Account for channels that have required components (MinGW)
@@ -144,43 +149,40 @@ jobs:
         rustup default "$channel"
         rustup target add "$JOB_TARGET"
 
-    - uses: taiki-e/install-action@920ab1831fbf4fb3ef75c8ead83556c918bb7290 # v2.79.8
+    - uses: taiki-e/install-action@7f4eb899022d8fe70b20c4f3de697aa85c309026 # v2.85.11
       with:
         tool: nextest@0.9.131
 
-    - uses: Swatinem/rust-cache@c19371144df3bb44fab255c43d04cbc2ab54d1c4 # v2.9.1
+    - uses: Swatinem/rust-cache@6323deb102c322ba6fcbdcafc7e3dddab59af2b6 # v2.9.2
       with:
         key: ${{ matrix.target }}
     - name: Cache Docker layers
-      uses: actions/cache@668228422ae6a00e4ad889ee87cd7109ec5666a7 # v5.0.4
+      uses: actions/cache@55cc8345863c7cc4c66a329aec7e433d2d1c52a9 # v6.1.0
       if: ${{ env.RUN_IN_DOCKER == 'true' }}
       with:
         path: /tmp/.buildx-cache
         key: ${{ matrix.target }}-buildx-${{ github.sha }}
         restore-keys: ${{ matrix.target }}-buildx-
     # Configure buildx to use Docker layer caching
-    - uses: docker/setup-buildx-action@4d04d5d9486b7bd6fa91e7baf45bbb4f8b9deedd # v4
+    - uses: docker/setup-buildx-action@bb05f3f5519dd87d3ba754cc423b652a5edd6d2c # v4.2.0
       if: ${{ env.RUN_IN_DOCKER == 'true' }}
 
     - name: Cache compiler-rt
       id: cache-compiler-rt
-      uses: actions/cache@668228422ae6a00e4ad889ee87cd7109ec5666a7 # v5.0.4
+      uses: actions/cache@55cc8345863c7cc4c66a329aec7e433d2d1c52a9 # v6.1.0
       with:
         path: compiler-rt
-        key: ${{ runner.os }}-compiler-rt-${{ hashFiles('ci/download-compiler-rt.sh') }}
+        key: ${{ runner.os }}-compiler-rt-${{ hashFiles('ci/download-compiler-rt.sh', 'ci/compiler-rt-patches') }}
     - name: Download compiler-rt reference sources
       if: steps.cache-compiler-rt.outputs.cache-hit != 'true'
       run: ./ci/download-compiler-rt.sh
-      shell: bash
     - run: echo "RUST_COMPILER_RT_ROOT=$(realpath ./compiler-rt)" >> "$GITHUB_ENV"
-      shell: bash
 
     - name: Download musl source
       run: ./ci/update-musl.sh
-      shell: bash
 
     - name: Verify API list
-      if: matrix.os == 'ubuntu-24.04' || contains(matrix.os, 'self-hosted')
+      if: matrix.os == 'ubuntu-26.04' || contains(matrix.os, 'self-hosted')
       run: |
         # Must be run on the host (not in Docker) because git and fs access is required.
         python3 etc/update-api-list.py --check
@@ -189,7 +191,6 @@ jobs:
     # Non-linux tests just use our raw script
     - name: Run locally
       if: ${{ env.RUN_IN_DOCKER != 'true' }}
-      shell: bash
       run: ./ci/run.sh "$JOB_TARGET"
 
     # Otherwise we use our docker containers to run builds
@@ -200,7 +201,6 @@ jobs:
     - name: Print test logs if available
       if: always()
       run: if [ -f "target/test-log.txt" ]; then cat target/test-log.txt; fi
-      shell: bash
 
     # Workaround to keep Docker cache smaller
     # https://github.com/docker/build-push-action/issues/252
@@ -213,10 +213,10 @@ jobs:
 
   clippy:
     name: Clippy
-    runs-on: ubuntu-24.04
+    runs-on: ubuntu-26.04
     timeout-minutes: 10
     steps:
-    - uses: actions/checkout@de0fac2e4500dabe0009e67214ff5f5447ce83dd # v6.0.2
+    - uses: actions/checkout@3d3c42e5aac5ba805825da76410c181273ba90b1 # v7.0.1
       with: { persist-credentials: false }
     # Unlike rustfmt, stable clippy does not work on code with nightly features.
     - name: Install nightly `clippy`
@@ -224,35 +224,35 @@ jobs:
         rustup update nightly --no-self-update
         rustup default nightly
         rustup component add clippy
-    - uses: Swatinem/rust-cache@c19371144df3bb44fab255c43d04cbc2ab54d1c4 # v2.9.1
+    - uses: Swatinem/rust-cache@6323deb102c322ba6fcbdcafc7e3dddab59af2b6 # v2.9.2
     - name: Download musl source
       run: ./ci/update-musl.sh
     - run: cargo clippy --workspace --all-targets
 
   zizmor:
     name: Zizmor (Static analysis for GitHub Actions)
-    runs-on: ubuntu-24.04
+    runs-on: ubuntu-26.04
     permissions:
       security-events: write
     timeout-minutes: 10
     steps:
-      - uses: actions/checkout@de0fac2e4500dabe0009e67214ff5f5447ce83dd # v6.0.2
+      - uses: actions/checkout@3d3c42e5aac5ba805825da76410c181273ba90b1 # v7.0.1
         with: { persist-credentials: false }
-      - uses: zizmorcore/zizmor-action@71321a20a9ded102f6e9ce5718a2fcec2c4f70d8 # v0.5.2
+      - uses: zizmorcore/zizmor-action@3dc1ecc9bcb9e94e9b2c709687979e1298497054 # v0.6.2
 
   build-custom:
     name: Build custom target
-    runs-on: ubuntu-24.04
+    runs-on: ubuntu-26.04
     timeout-minutes: 10
     steps:
-    - uses: actions/checkout@de0fac2e4500dabe0009e67214ff5f5447ce83dd # v6.0.2
+    - uses: actions/checkout@3d3c42e5aac5ba805825da76410c181273ba90b1 # v7.0.1
       with: { persist-credentials: false }
     - name: Install Rust
       run: |
         rustup update nightly --no-self-update
         rustup default nightly
         rustup component add rust-src
-    - uses: Swatinem/rust-cache@c19371144df3bb44fab255c43d04cbc2ab54d1c4 # v2.9.1
+    - uses: Swatinem/rust-cache@6323deb102c322ba6fcbdcafc7e3dddab59af2b6 # v2.9.2
     - run: |
         # Ensure we can build with custom target.json files (these can interact
         # poorly with build scripts)
@@ -264,17 +264,17 @@ jobs:
   # FIXME: move this target to test job once https://github.com/rust-lang/rust/pull/150138 merged.
   build-thumbv6k:
     name: Build thumbv6k
-    runs-on: ubuntu-24.04
+    runs-on: ubuntu-26.04
     timeout-minutes: 10
     steps:
-    - uses: actions/checkout@de0fac2e4500dabe0009e67214ff5f5447ce83dd # v6.0.2
+    - uses: actions/checkout@3d3c42e5aac5ba805825da76410c181273ba90b1 # v7.0.1
       with: { persist-credentials: false }
     - name: Install Rust
       run: |
         rustup update nightly --no-self-update
         rustup default nightly
         rustup component add rust-src
-    - uses: Swatinem/rust-cache@c19371144df3bb44fab255c43d04cbc2ab54d1c4 # v2.9.1
+    - uses: Swatinem/rust-cache@6323deb102c322ba6fcbdcafc7e3dddab59af2b6 # v2.9.2
     - run: |
         cargo build -p compiler_builtins -p libm \
           --target etc/thumbv6-none-eabi.json \
@@ -289,24 +289,24 @@ jobs:
       matrix:
         include:
         - target: aarch64-unknown-linux-gnu
-          os: ubuntu-24.04-arm
+          os: ubuntu-26.04-arm
         - target: i686-unknown-linux-gnu
-          os: ubuntu-24.04
+          os: ubuntu-26.04
         - target: x86_64-unknown-linux-gnu
-          os: ubuntu-24.04
+          os: ubuntu-26.04
     runs-on: ${{ matrix.os }}
     env:
       JOB_TARGET: ${{ matrix.target }}
     steps:
-    - uses: actions/checkout@de0fac2e4500dabe0009e67214ff5f5447ce83dd # v6.0.2
+    - uses: actions/checkout@3d3c42e5aac5ba805825da76410c181273ba90b1 # v7.0.1
       with: { persist-credentials: false }
-    - uses: taiki-e/install-action@920ab1831fbf4fb3ef75c8ead83556c918bb7290 # v2.79.8
+    - uses: taiki-e/install-action@7f4eb899022d8fe70b20c4f3de697aa85c309026 # v2.85.11
       with:
         tool: cargo-binstall@1.17.7
 
     - name: Set up dependencies
       run: ./ci/install-bench-deps.sh "$JOB_TARGET"
-    - uses: Swatinem/rust-cache@c19371144df3bb44fab255c43d04cbc2ab54d1c4 # v2.9.1
+    - uses: Swatinem/rust-cache@6323deb102c322ba6fcbdcafc7e3dddab59af2b6 # v2.9.2
       with:
         key: ${{ matrix.target }}
     - name: Download musl source
@@ -319,7 +319,7 @@ jobs:
       run: ./ci/bench-icount.sh "$JOB_TARGET"
 
     - name: Upload the benchmark baseline
-      uses: actions/upload-artifact@bbbca2ddaa5d8feaa63e36b76fdaad77386f024f # v7.0.0
+      uses: actions/upload-artifact@043fb46d1a93c77aae656e7c1c64a875d1fc6a0a # v7.0.1
       with:
         name: ${{ env.BASELINE_NAME }}
         path: ${{ env.BASELINE_NAME }}.tar.xz
@@ -327,38 +327,36 @@ jobs:
     - name: Print test logs if available
       if: always()
       run: if [ -f "target/test-log.txt" ]; then cat target/test-log.txt; fi
-      shell: bash
 
   miri:
     name: Miri
-    runs-on: ubuntu-24.04
+    runs-on: ubuntu-26.04
     timeout-minutes: 10
     steps:
-    - uses: actions/checkout@de0fac2e4500dabe0009e67214ff5f5447ce83dd # v6.0.2
+    - uses: actions/checkout@3d3c42e5aac5ba805825da76410c181273ba90b1 # v7.0.1
       with: { persist-credentials: false }
     - name: Install Rust (rustup)
       run: rustup update nightly --no-self-update && rustup default nightly
-      shell: bash
     - run: rustup component add miri
     - run: cargo miri setup
-    - uses: Swatinem/rust-cache@c19371144df3bb44fab255c43d04cbc2ab54d1c4 # v2.9.1
+    - uses: Swatinem/rust-cache@6323deb102c322ba6fcbdcafc7e3dddab59af2b6 # v2.9.2
     - run: ./ci/miri.sh
 
   msrv:
     name: Check libm MSRV
-    runs-on: ubuntu-24.04
+    runs-on: ubuntu-26.04
     timeout-minutes: 10
     env:
       RUSTFLAGS: # No need to check warnings on old MSRV, unset `-Dwarnings`
     steps:
-    - uses: actions/checkout@de0fac2e4500dabe0009e67214ff5f5447ce83dd # v6.0.2
+    - uses: actions/checkout@3d3c42e5aac5ba805825da76410c181273ba90b1 # v7.0.1
       with: { persist-credentials: false }
     - name: Install Rust
       run: |
         msrv="$(perl -ne 'print if s/rust-version\s*=\s*"(.*)"/\1/g' libm/Cargo.toml)"
         echo "MSRV: $msrv"
         rustup update "$msrv" --no-self-update && rustup default "$msrv"
-    - uses: Swatinem/rust-cache@c19371144df3bb44fab255c43d04cbc2ab54d1c4 # v2.9.1
+    - uses: Swatinem/rust-cache@6323deb102c322ba6fcbdcafc7e3dddab59af2b6 # v2.9.2
     - run: |
         # FIXME(msrv): Remove the workspace Cargo.toml so 1.63 cargo doesn't see
         # `edition = "2024"` and get spooked.
@@ -367,10 +365,10 @@ jobs:
 
   rustfmt:
     name: Rustfmt
-    runs-on: ubuntu-24.04
+    runs-on: ubuntu-26.04
     timeout-minutes: 10
     steps:
-    - uses: actions/checkout@de0fac2e4500dabe0009e67214ff5f5447ce83dd # v6.0.2
+    - uses: actions/checkout@3d3c42e5aac5ba805825da76410c181273ba90b1 # v7.0.1
       with: { persist-credentials: false }
     - name: Install nightly `rustfmt`
       run: rustup set profile minimal && rustup default nightly && rustup component add rustfmt
@@ -382,7 +380,7 @@ jobs:
       # Wait on `clippy` so we have some confidence that the crate will build
       - clippy
       - calculate_vars
-    runs-on: ubuntu-24.04
+    runs-on: ubuntu-26.04
     timeout-minutes: 240 # 4 hours
     strategy:
       matrix:
@@ -394,20 +392,19 @@ jobs:
     env:
       TO_TEST: ${{ matrix.to_test }}
     steps:
-      - uses: actions/checkout@de0fac2e4500dabe0009e67214ff5f5447ce83dd # v6.0.2
+      - uses: actions/checkout@3d3c42e5aac5ba805825da76410c181273ba90b1 # v7.0.1
         with: { persist-credentials: false }
       - name: Install Rust
         run: |
           rustup update nightly --no-self-update
           rustup default nightly
-      - uses: Swatinem/rust-cache@c19371144df3bb44fab255c43d04cbc2ab54d1c4 # v2.9.1
+      - uses: Swatinem/rust-cache@6323deb102c322ba6fcbdcafc7e3dddab59af2b6 # v2.9.2
       - name: download musl source
         run: ./ci/update-musl.sh
       - name: Run extensive tests
         run: ./ci/run-extensive.sh
       - name: Print test logs if available
         run: if [ -f "target/test-log.txt" ]; then cat target/test-log.txt; fi
-        shell: bash
 
   success:
     needs:
@@ -421,7 +418,7 @@ jobs:
       - rustfmt
       - test
       - zizmor
-    runs-on: ubuntu-24.04
+    runs-on: ubuntu-26.04
     timeout-minutes: 10
     # GitHub branch protection is exceedingly silly and treats "jobs skipped because a dependency
     # failed" as success. So we have to do some contortions to ensure the job fails if any of its
diff --git a/library/compiler-builtins/.github/workflows/publish.yaml b/library/compiler-builtins/.github/workflows/publish.yaml
index aa742914a5344..02ddf0babdf40 100644
--- a/library/compiler-builtins/.github/workflows/publish.yaml
+++ b/library/compiler-builtins/.github/workflows/publish.yaml
@@ -13,13 +13,13 @@ jobs:
     runs-on: ubuntu-24.04
     environment: publish
     steps:
-      - uses: actions/checkout@de0fac2e4500dabe0009e67214ff5f5447ce83dd # v6.0.2
+      - uses: actions/checkout@3d3c42e5aac5ba805825da76410c181273ba90b1 # v7.0.1
         with:
           persist-credentials: false
           fetch-depth: 0
       - name: Install Rust (rustup)
         run: rustup update nightly --no-self-update && rustup default nightly
       - name: Run release-plz
-        uses: release-plz/action@1528104d2ca23787631a1c1f022abb64b34c1e11 # v0.5
+        uses: release-plz/action@2eb1d8bcb770b4c48ccfaad919734b38b51958c9 # v0.5
         env:
           GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
diff --git a/library/compiler-builtins/.github/workflows/rustc-pull.yml b/library/compiler-builtins/.github/workflows/rustc-pull.yml
index ff8305d3729fd..34e78e445677c 100644
--- a/library/compiler-builtins/.github/workflows/rustc-pull.yml
+++ b/library/compiler-builtins/.github/workflows/rustc-pull.yml
@@ -13,7 +13,7 @@ env:
 jobs:
   pull:
     if: github.repository == 'rust-lang/compiler-builtins'
-    uses: rust-lang/josh-sync/.github/workflows/rustc-pull.yml@8970a6eb3a6095db68e4d765b3b5fba5e9c42cf6 # main
+    uses: rust-lang/josh-sync/.github/workflows/rustc-pull.yml@00d007cf377c524bc2968b40a61ef1d2ce20e283 # main
     with:
       github-app-id: ${{ vars.APP_CLIENT_ID }}
       pr-author: "workflows-compiler-builtins[bot]"
diff --git a/library/compiler-builtins/.gitignore b/library/compiler-builtins/.gitignore
index 1137a19cf093b..ec7130db73802 100644
--- a/library/compiler-builtins/.gitignore
+++ b/library/compiler-builtins/.gitignore
@@ -1,11 +1,6 @@
 # Rust files
 target
 
-# We have a couple of potential Cargo.lock files, but we only the root
-# workspace should have dependencies other than (optional) `cc`.
-Cargo.lock
-!/Cargo.lock
-
 # Sources for external files
 compiler-rt
 *.tar.gz
diff --git a/library/compiler-builtins/Cargo.lock b/library/compiler-builtins/Cargo.lock
index ed27483d44b4e..1c216f5165b54 100644
--- a/library/compiler-builtins/Cargo.lock
+++ b/library/compiler-builtins/Cargo.lock
@@ -10,9 +10,9 @@ checksum = "320119579fcad9c21884f5c4861d16174d0e06250625266f50fe6898340abefa"
 
 [[package]]
 name = "aho-corasick"
-version = "1.1.4"
+version = "1.1.5"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "ddd31a130427c27518df266943a5308ed92d4b226cc639f5a8f1002816174301"
+checksum = "c982642fa9e8606056828ee9a8505737230110bb1099153c79efe865c59d12ba"
 dependencies = [
  "memchr",
 ]
@@ -84,9 +84,9 @@ dependencies = [
 
 [[package]]
 name = "anyhow"
-version = "1.0.102"
+version = "1.0.104"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "7f202df86484c868dbad7eaa557ef785d5c66295e41b460ef922eca0723b842c"
+checksum = "330a5ed07fa54e4702c9d6c4174f74427fc0ef6e214bbd677ae50a5099946470"
 
 [[package]]
 name = "api-list-common"
@@ -94,9 +94,9 @@ version = "0.1.0"
 
 [[package]]
 name = "assert_cmd"
-version = "2.2.1"
+version = "2.2.2"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "39bae1d3fa576f7c6519514180a72559268dd7d1fe104070956cb687bc6673bd"
+checksum = "2aa3a22042e45de04255c7bf3626e239f450200fd0493c1e382263544b20aea6"
 dependencies = [
  "anstyle",
  "bstr",
@@ -109,9 +109,9 @@ dependencies = [
 
 [[package]]
 name = "autocfg"
-version = "1.5.0"
+version = "1.5.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "c08606f8c3cbf4ce6ec8e28fb0014a2c086708fe954eaa885384a6165172e7e8"
+checksum = "f2032f911046de80f0a198e0901378627c33f59ea0ac00e363d481118bd70a53"
 
 [[package]]
 name = "az"
@@ -121,29 +121,31 @@ checksum = "be5eb007b7cacc6c660343e96f650fedf4b5a77512399eb952ca6642cf8d13f7"
 
 [[package]]
 name = "bincode-next"
-version = "2.1.0"
+version = "3.1.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "dbe9e7e6d14aeb39557f226bff158a30e367fac279d0e69b8b42fb41999f9a86"
+checksum = "1d6626829353ae29293be5c86f42de5f0468bc758af074b0c7d08f07e538ccbc"
 dependencies = [
+ "pastey",
+ "rapidhash",
  "serde",
  "unty-next",
 ]
 
 [[package]]
 name = "bitflags"
-version = "2.11.1"
+version = "2.13.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "c4512299f36f043ab09a583e57bceb5a5aab7a73db1805848e8fef3c9e8c78b3"
+checksum = "b588b76d00fde79687d7646a9b5bdf3cc0f655e0bbd080335a95d7e96f3587da"
 
 [[package]]
 name = "bstr"
-version = "1.12.1"
+version = "1.13.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "63044e1ae8e69f3b5a92c736ca6269b8d12fa7efe39bf34ddb06d102cf0e2cab"
+checksum = "1f7dc094d718f2e1c1559ad110e27eeaae14a5465d3d56dd6dbd793079fbd530"
 dependencies = [
  "memchr",
  "regex-automata",
- "serde",
+ "serde_core",
 ]
 
 [[package]]
@@ -160,9 +162,9 @@ dependencies = [
 
 [[package]]
 name = "bumpalo"
-version = "3.20.2"
+version = "3.20.3"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "5d20789868f4b01b2f2caec9f5c4e0213b41e3e5702a50157d699ae31ced2fcb"
+checksum = "72f5acc6cb2ba439de613abc23857ec3d78374d8ed5ac84e9d11336e87da8649"
 
 [[package]]
 name = "cast"
@@ -172,9 +174,9 @@ checksum = "37b2a672a2cb129a2e41c10b1224bb368f9f37a2b16b612598138befd7b37eb5"
 
 [[package]]
 name = "cc"
-version = "1.2.61"
+version = "1.4.2"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "d16d90359e986641506914ba71350897565610e87ce0ad9e6f28569db3dd5c6d"
+checksum = "5d262e149917187838d5b42777c8253bcb64500067342904e7d429499a6f277e"
 dependencies = [
  "find-msvc-tools",
  "shlex",
@@ -188,9 +190,9 @@ checksum = "9330f8b2ff13f34540b44e946ef35111825727b38d33286ef986142615121801"
 
 [[package]]
 name = "chacha20"
-version = "0.10.0"
+version = "0.10.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "6f8d983286843e49675a4b7a2d174efe136dc93a18d69130dd18198a6c167601"
+checksum = "d524456ba66e72eb8b115ff89e01e497f8e6d11d78b70b1aa13c0fbd97540a81"
 dependencies = [
  "cfg-if",
  "cpufeatures",
@@ -226,9 +228,9 @@ dependencies = [
 
 [[package]]
 name = "clap"
-version = "4.6.1"
+version = "4.6.6"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "1ddb117e43bbf7dacf0a4190fef4d345b9bad68dfc649cb349e7d17d28428e51"
+checksum = "473c7e07f409a8d772161724aa8db6a765a2532a70f9667eeb7b49d3d02fbdca"
 dependencies = [
  "clap_builder",
  "clap_derive",
@@ -236,9 +238,9 @@ dependencies = [
 
 [[package]]
 name = "clap_builder"
-version = "4.6.0"
+version = "4.6.6"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "714a53001bf66416adb0e2ef5ac857140e7dc3a0c48fb28b2f10762fc4b5069f"
+checksum = "7b48fea5a88e9ae728a2dcbedbfc0e730f7d60da42e1cb049a83c9fb8b789889"
 dependencies = [
  "anstream",
  "anstyle",
@@ -248,14 +250,14 @@ dependencies = [
 
 [[package]]
 name = "clap_derive"
-version = "4.6.1"
+version = "4.6.4"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "f2ce8604710f6733aa641a2b3731eaa1e8b3d9973d5e3565da11800813f997a9"
+checksum = "d012d2b9d65aca7f18f4d9878a045bc17899bba951561ba5ec3c2ba1eed9a061"
 dependencies = [
  "heck",
  "proc-macro2",
  "quote",
- "syn",
+ "syn 3.0.3",
 ]
 
 [[package]]
@@ -279,9 +281,9 @@ dependencies = [
 
 [[package]]
 name = "console"
-version = "0.16.3"
+version = "0.16.4"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "d64e8af5551369d19cf50138de61f1c42074ab970f74e99be916646777f8fc87"
+checksum = "4fe5f465a4f6fee88fad41b85d990f84c835335e85b5d9e6e63e0d06d28cba7c"
 dependencies = [
  "encode_unicode",
  "libc",
@@ -342,9 +344,9 @@ dependencies = [
 
 [[package]]
 name = "crossbeam-deque"
-version = "0.8.6"
+version = "0.8.7"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "9dd111b7b7f7d55b72c0a6ae361660ee5853c9af73f70c3c2ef6858b950e2e51"
+checksum = "5181e0de7b61eb03a81e347d6dd8797bae9da5146707b51077e2d71a54ec0ceb"
 dependencies = [
  "crossbeam-epoch",
  "crossbeam-utils",
@@ -352,18 +354,18 @@ dependencies = [
 
 [[package]]
 name = "crossbeam-epoch"
-version = "0.9.18"
+version = "0.9.20"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "5b82ac4a3c2ca9c3460964f020e1402edd5753411d7737aa39c3714ad1b5420e"
+checksum = "2d6914041f254d6e9176c01941b21115dcfb7089e55135a35411081bd106ef3f"
 dependencies = [
  "crossbeam-utils",
 ]
 
 [[package]]
 name = "crossbeam-utils"
-version = "0.8.21"
+version = "0.8.22"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "d0a5c400df2834b80a4c3327b3aad3a4c4cd4de0629063962b03235697506a28"
+checksum = "61803da095bee82a81bb1a452ecc25d3b2f1416d1897eb86430c6159ef717c17"
 
 [[package]]
 name = "crunchy"
@@ -389,7 +391,7 @@ dependencies = [
  "proc-macro2",
  "quote",
  "rustc_version",
- "syn",
+ "syn 2.0.119",
 ]
 
 [[package]]
@@ -406,9 +408,19 @@ checksum = "6184e33543162437515c2e2b48714794e37845ec9851711914eec9d308f6ebe8"
 
 [[package]]
 name = "either"
-version = "1.15.0"
+version = "1.17.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "48c757948c5ede0e46177b7add2e67155f70e33c07fea8284df6576da70b3719"
+checksum = "9e5e8f6c15a24b9a3ee5efec809ccd006d3b30e8b3bb63c39af737c7f87daa1d"
+
+[[package]]
+name = "either-or-both"
+version = "0.3.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "6717164c227120ba9ddf3e2b32305fc0122741d3ee41a54968eae7573ee01933"
+dependencies = [
+ "indexmap",
+ "serde",
+]
 
 [[package]]
 name = "encode_unicode"
@@ -440,15 +452,15 @@ checksum = "5692dd7b5a1978a5aeb0ce83b7655c58ca8efdcb79d21036ea249da95afec2c6"
 
 [[package]]
 name = "fastrand"
-version = "2.4.1"
+version = "2.5.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "9f1f227452a390804cdb637b74a86990f2a7d7ba4b7d5693aac9b4dd6defd8d6"
+checksum = "da7c62ceae207dd37ea5b845da6a0696c799f85e97da1ab5b7910be3c1c80223"
 
 [[package]]
 name = "find-msvc-tools"
-version = "0.1.9"
+version = "0.1.10"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "5baebc0774151f905a1a2cc41989300b1e6fbb29aff0ceffa1064fdd3088d582"
+checksum = "26b73573e6edcd2af0cdf47bd6cb58f0b3839491263c314eaad1ccf24430e1de"
 
 [[package]]
 name = "flate2"
@@ -460,29 +472,23 @@ dependencies = [
  "miniz_oxide",
 ]
 
-[[package]]
-name = "foldhash"
-version = "0.1.5"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "d9c4f5dac5e15c24eb999c26181a6ca40b39fe946cbe4c263c7209467bc83af2"
-
 [[package]]
 name = "futures-core"
-version = "0.3.32"
+version = "0.3.33"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "7e3450815272ef58cec6d564423f6e755e25379b217b0bc688e295ba24df6b1d"
+checksum = "2cd50c473c80f6d7c3670a752354b8e569b1a7cbfdc0419ec88e5edad85e0dc7"
 
 [[package]]
 name = "futures-task"
-version = "0.3.32"
+version = "0.3.33"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "037711b3d59c33004d3856fbdc83b99d4ff37a24768fa1be9ce3538a1cde4393"
+checksum = "b231ed28831efb4a61a08580c4bc233ec56bc009f4cd8f52da2c3cb97df0c109"
 
 [[package]]
 name = "futures-util"
-version = "0.3.32"
+version = "0.3.33"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "389ca41296e6190b48053de0321d02a77f32f8a5d2461dd38762c0593805c6d6"
+checksum = "a77a90a256fce34da66415271e30f94ee91c57b04b8a2c042d9cf3220179deaa"
 dependencies = [
  "futures-core",
  "futures-task",
@@ -501,25 +507,23 @@ dependencies = [
 
 [[package]]
 name = "getrandom"
-version = "0.4.2"
+version = "0.4.3"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "0de51e6874e94e7bf76d726fc5d13ba782deca734ff60d5bb2fb2607c7406555"
+checksum = "300e883d756b2e4ec94e02791f39b04b522276138852cfc41d9fb7e904106099"
 dependencies = [
  "cfg-if",
  "js-sys",
  "libc",
  "r-efi",
  "rand_core",
- "wasip2",
- "wasip3",
  "wasm-bindgen",
 ]
 
 [[package]]
 name = "glob"
-version = "0.3.3"
+version = "0.3.4"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "0cc23270f6e1808e30a928bdc84dea0b9b4136a8bc82338574f23baf47bbd280"
+checksum = "e4eba85ea1d0a966a983acd07deee566e67395d2d96b6fb39e62b5a833f1eb0b"
 
 [[package]]
 name = "gmp-mpfr-sys"
@@ -533,9 +537,9 @@ dependencies = [
 
 [[package]]
 name = "gungraun"
-version = "0.19.0"
+version = "0.19.4"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "a710656785d3ed71a73a1007956874d6ebfdbc2f8660c492bb8d838c91e3f085"
+checksum = "9300d38d30facf6870c15bc9e243edcc47e5ddc270c9d2c1ae824a00b1faea79"
 dependencies = [
  "bincode-next",
  "derive_more",
@@ -545,26 +549,27 @@ dependencies = [
 
 [[package]]
 name = "gungraun-macros"
-version = "0.9.0"
+version = "0.9.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "4cc6269e89921872ec32af29af3a992618b9bd2ef47cbf3704af476066cb7182"
+checksum = "d7f3214bae6cfd6739f4f29edb262bae439c6393a7b7b12c4eeb96417c2e50df"
 dependencies = [
  "derive_more",
- "proc-macro-error2",
+ "proc-macro-error3",
  "proc-macro2",
  "quote",
  "rustc_version",
  "serde",
  "serde_json",
- "syn",
+ "syn 2.0.119",
 ]
 
 [[package]]
 name = "gungraun-runner"
-version = "0.19.0"
+version = "0.19.4"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "12016920cc6ba0a8aefe276c8f19421a3bf7a125385e25697658b9dd66bde024"
+checksum = "47c68c92812da579a2510a2cc702d5aa3251992b9662d4a98502ca46e0cbe16e"
 dependencies = [
+ "either-or-both",
  "serde",
 ]
 
@@ -581,18 +586,9 @@ dependencies = [
 
 [[package]]
 name = "hashbrown"
-version = "0.15.5"
+version = "0.17.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "9229cfe53dfd69f0609a49f65461bd93001ea1ef889cd5529dd176593f5338a1"
-dependencies = [
- "foldhash",
-]
-
-[[package]]
-name = "hashbrown"
-version = "0.17.0"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "4f467dd6dccf739c208452f8014c75c18bb8301b050ad1cfb27153803edb0f51"
+checksum = "ed5909b6e89a2db4456e54cd5f673791d7eca6732202bbf2a9cc504fe2f9b84a"
 
 [[package]]
 name = "heck"
@@ -600,12 +596,6 @@ version = "0.5.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "2304e00983f87ffb38b55b444b5e3b60a884b5d30c0fca7d82fe33449bbe55ea"
 
-[[package]]
-name = "id-arena"
-version = "2.3.0"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "3d3067d79b975e8844ca9eb072e16b31c3c1c36928edf9c6789548c524d0d954"
-
 [[package]]
 name = "indexmap"
 version = "2.14.0"
@@ -613,16 +603,14 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "d466e9454f08e4a911e14806c24e16fba1b4c121d1ea474396f396069cf949d9"
 dependencies = [
  "equivalent",
- "hashbrown 0.17.0",
- "serde",
- "serde_core",
+ "hashbrown",
 ]
 
 [[package]]
 name = "indicatif"
-version = "0.18.4"
+version = "0.18.6"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "25470f23803092da7d239834776d653104d551bc4d7eacaf31e6837854b8e9eb"
+checksum = "9433806cd6b4ec1aba79c021c7e4c58fb4c3b9977c085062e611ac929998fb0c"
 dependencies = [
  "console",
  "portable-atomic",
@@ -653,27 +641,20 @@ checksum = "8f42a60cbdf9a97f5d2305f08a87dc4e09308d1276d28c869c684d7777685682"
 
 [[package]]
 name = "js-sys"
-version = "0.3.97"
+version = "0.3.104"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "a1840c94c045fbcf8ba2812c95db44499f7c64910a912551aaaa541decebcacf"
+checksum = "0e0c1080212aad755ea003d18543e8768dd432c48819efd73a7bf1e39b7a5a3a"
 dependencies = [
  "cfg-if",
  "futures-util",
- "once_cell",
  "wasm-bindgen",
 ]
 
-[[package]]
-name = "leb128fmt"
-version = "0.1.0"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "09edd9e8b54e49e587e4f6295a7d29c3ea94d469cb40ab8ca70b288248a81db2"
-
 [[package]]
 name = "libc"
-version = "0.2.186"
+version = "0.2.189"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "68ab91017fe16c622486840e4c83c9a37afeff978bd239b5293d61ece587de66"
+checksum = "3eaf3ede3fee6db1a4c2ee091bf8a8b4dccdc6d17f656fb07896ee72867612f2"
 
 [[package]]
 name = "libm"
@@ -696,7 +677,7 @@ dependencies = [
  "heck",
  "proc-macro2",
  "quote",
- "syn",
+ "syn 3.0.3",
 ]
 
 [[package]]
@@ -740,17 +721,11 @@ version = "0.12.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "32a66949e030da00e8c7d4434b251670a91556f4144941d37452769c25d58a53"
 
-[[package]]
-name = "log"
-version = "0.4.29"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "5e5032e24019045c762d3c0f28f5b6b8bbf38563a65908389bf7978758920897"
-
 [[package]]
 name = "memchr"
-version = "2.8.0"
+version = "2.8.3"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "f8ca58f447f06ed17d5fc4043ce1b10dd205e060fb3ce5b979b8ed8e59ff3f79"
+checksum = "cf8baf1c55e62ffcace7a9f06f4bd9cd3f0c4beb022d3b367256b91b87513d98"
 
 [[package]]
 name = "miniz_oxide"
@@ -772,13 +747,13 @@ dependencies = [
 
 [[package]]
 name = "no-panic"
-version = "0.1.36"
+version = "0.1.37"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "f967505aabc8af5752d098c34146544a43684817cdba8f9725b292530cabbf53"
+checksum = "fc80370b4544f28ffa317e3c3474ee3ecbfe269196c01ae657d9f837a7d944a1"
 dependencies = [
  "proc-macro2",
  "quote",
- "syn",
+ "syn 3.0.3",
 ]
 
 [[package]]
@@ -792,14 +767,14 @@ dependencies = [
 
 [[package]]
 name = "object"
-version = "0.39.1"
+version = "0.40.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "2e5a6c098c7a3b6547378093f5cc30bc54fd361ce711e05293a5cc589562739b"
+checksum = "dd229a0361b9d0d4396176e02d65897f487eebeab7caa6d443855ee152ca0b9c"
 dependencies = [
  "flate2",
  "memchr",
  "ruzstd",
- "wasmparser 0.247.0",
+ "wasmparser",
 ]
 
 [[package]]
@@ -840,6 +815,12 @@ version = "1.0.15"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "57c0d7b74b563b49d38dae00a0c37d4d6de9b432382b2892f0574ddcae73fd0a"
 
+[[package]]
+name = "pastey"
+version = "0.2.3"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "2ee67f1008b1ba2321834326597b8e186293b049a023cdef258527550b9935b4"
+
 [[package]]
 name = "pin-project-lite"
 version = "0.2.17"
@@ -876,9 +857,9 @@ dependencies = [
 
 [[package]]
 name = "portable-atomic"
-version = "1.13.1"
+version = "1.15.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "c33a9471896f1c69cecef8d20cbe2f7accd12527ce60845ff44c153bb2a21b49"
+checksum = "05c8b63e8d9609db387f0324918f81d68fe27748f084ef092fb35954d0539a85"
 
 [[package]]
 name = "ppv-lite86"
@@ -927,51 +908,41 @@ dependencies = [
 ]
 
 [[package]]
-name = "prettyplease"
-version = "0.2.37"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "479ca8adacdd7ce8f1fb39ce9ecccbfe93a3f1344b3d0d97f20bc0196208f62b"
-dependencies = [
- "proc-macro2",
- "syn",
-]
-
-[[package]]
-name = "proc-macro-error-attr2"
-version = "2.0.0"
+name = "proc-macro-error-attr3"
+version = "3.1.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "96de42df36bb9bba5542fe9f1a054b8cc87e172759a1868aa05c1f3acc89dfc5"
+checksum = "b0084e6206a967a2dad822180626b2f6b07a3b379325e8f1ec0438e33a469ba7"
 dependencies = [
  "proc-macro2",
  "quote",
 ]
 
 [[package]]
-name = "proc-macro-error2"
-version = "2.0.1"
+name = "proc-macro-error3"
+version = "3.1.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "11ec05c52be0a07b08061f7dd003e7d7092e0472bc731b4af7bb1ef876109802"
+checksum = "0cf066225f2373bc711684792b69bdeac0356019b007e721090c24d92d5d5a50"
 dependencies = [
- "proc-macro-error-attr2",
+ "proc-macro-error-attr3",
  "proc-macro2",
  "quote",
- "syn",
+ "syn 3.0.3",
 ]
 
 [[package]]
 name = "proc-macro2"
-version = "1.0.106"
+version = "1.0.107"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "8fd00f0bb2e90d81d1044c2b32617f68fcb9fa3bb7640c23e9c748e53fb30934"
+checksum = "985e7ec9bb745e6ce6535b544d84d6cd6f7ad8bd711c398938ae983b91a766d9"
 dependencies = [
  "unicode-ident",
 ]
 
 [[package]]
 name = "quote"
-version = "1.0.45"
+version = "1.0.47"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "41f2619966050689382d2b44f664f4bc593e129785a36d6ee376ddf37259b924"
+checksum = "1fbf4db142a473a8d80c26bbf18454ed458bf8d26c8219c331daecfdbd079001"
 dependencies = [
  "proc-macro2",
 ]
@@ -984,9 +955,9 @@ checksum = "f8dcc9c7d52a811697d2151c701e0d08956f92b0e24136cf4cf27b57a6a0d9bf"
 
 [[package]]
 name = "rand"
-version = "0.10.1"
+version = "0.10.2"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "d2e8e8bcc7961af1fdac401278c6a831614941f6164ee3bf4ce61b7edb162207"
+checksum = "c7f5fa3a058cd35567ef9bfa5e75732bee0f9e4c55fa90477bef2dfcdbc4be80"
 dependencies = [
  "chacha20",
  "getrandom",
@@ -1011,13 +982,22 @@ checksum = "63b8176103e19a2643978565ca18b50549f6101881c443590420e4dc998a3c69"
 
 [[package]]
 name = "rand_xoshiro"
-version = "0.8.0"
+version = "0.8.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "1f0b2cc7bfeef8f0320ca45f88b00157a03c67137022d59393614352d6bf4312"
+checksum = "662effc7698e08ea324d3acccf8d9d7f7bf79b9785e270a174ea36e56900c91d"
 dependencies = [
  "rand_core",
 ]
 
+[[package]]
+name = "rapidhash"
+version = "4.5.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "5da7e78a036ce858e8d55b7e7dc8ba3a88b78350fd2155d3591bbd966b58589e"
+dependencies = [
+ "rustversion",
+]
+
 [[package]]
 name = "rayon"
 version = "1.12.0"
@@ -1040,9 +1020,9 @@ dependencies = [
 
 [[package]]
 name = "regex"
-version = "1.12.3"
+version = "1.13.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "e10754a14b9137dd7b1e3e5b0493cc9171fdd105e0ab477f51b72e7f3ac0e276"
+checksum = "f020237b6c8eed93db2e2cb53c00c60a8e1bc73da7d073199a1180401450218d"
 dependencies = [
  "aho-corasick",
  "memchr",
@@ -1052,9 +1032,9 @@ dependencies = [
 
 [[package]]
 name = "regex-automata"
-version = "0.4.14"
+version = "0.4.18"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "6e1dd4122fc1595e8162618945476892eefca7b88c52820e74af6262213cae8f"
+checksum = "ad8553b9b26413251cbf30e620595c7a41b3887f03da04579c0e6b0d6a06b4b2"
 dependencies = [
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  "memchr",
@@ -1063,9 +1043,9 @@ dependencies = [
 
 [[package]]
 name = "regex-syntax"
-version = "0.8.10"
+version = "0.8.11"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "dc897dd8d9e8bd1ed8cdad82b5966c3e0ecae09fb1907d58efaa013543185d0a"
+checksum = "d6f6ff9a378485b298a5286656da665ba74413d36db0979633275d2e708145d4"
 
 [[package]]
 name = "rug"
@@ -1113,15 +1093,15 @@ dependencies = [
 
 [[package]]
 name = "rustversion"
-version = "1.0.22"
+version = "1.0.23"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "b39cdef0fa800fc44525c84ccb54a029961a8215f9619753635a9c0d2538d46d"
+checksum = "cf54715a573b99ac80df0bc206da022bcd442c974952c7b9720069370852e21f"
 
 [[package]]
 name = "ruzstd"
-version = "0.8.2"
+version = "0.9.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "e5ff0cc5e135c8870a775d3320910cd9b564ec036b4dc0b8741629020be63f01"
+checksum = "a252f5e20f038fe7b4ea53e073e65398d652c864cc162fc77c56c2f13717b888"
 dependencies = [
  "twox-hash",
 ]
@@ -1143,9 +1123,9 @@ checksum = "8a7852d02fc848982e0c167ef163aaff9cd91dc640ba85e263cb1ce46fae51cd"
 
 [[package]]
 name = "serde"
-version = "1.0.228"
+version = "1.0.229"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "9a8e94ea7f378bd32cbbd37198a4a91436180c5bb472411e48b5ec2e2124ae9e"
+checksum = "4148590afebada386688f18773da617792bf2ef03ffc1e4cbd2b1d45b023e0ba"
 dependencies = [
  "serde_core",
  "serde_derive",
@@ -1153,29 +1133,29 @@ dependencies = [
 
 [[package]]
 name = "serde_core"
-version = "1.0.228"
+version = "1.0.229"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "41d385c7d4ca58e59fc732af25c3983b67ac852c1a25000afe1175de458b67ad"
+checksum = "67dca2c9c51e58a4791a4b1ed58308b39c64224d349a935ab5039aa360942a48"
 dependencies = [
  "serde_derive",
 ]
 
 [[package]]
 name = "serde_derive"
-version = "1.0.228"
+version = "1.0.229"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "d540f220d3187173da220f885ab66608367b6574e925011a9353e4badda91d79"
+checksum = "e7a5d71263a5a7d47b41f6b3f06ba276f10cc18b0931f1799f710578e2309348"
 dependencies = [
  "proc-macro2",
  "quote",
- "syn",
+ "syn 3.0.3",
 ]
 
 [[package]]
 name = "serde_json"
-version = "1.0.149"
+version = "1.0.151"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "83fc039473c5595ace860d8c4fafa220ff474b3fc6bfdb4293327f1a37e94d86"
+checksum = "c841b55ecdae098c80dcae9cf767f6f8a0c2cdb3416bbef72181df4d0fe73f14"
 dependencies = [
  "itoa",
  "memchr",
@@ -1186,15 +1166,15 @@ dependencies = [
 
 [[package]]
 name = "shlex"
-version = "1.3.0"
+version = "2.0.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "0fda2ff0d084019ba4d7c6f371c95d8fd75ce3524c3cb8fb653a3023f6323e64"
+checksum = "f8fadd59c855ef2080decdef8ff161eb6661b86933c9d82e5ba29dc602a55aba"
 
 [[package]]
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-version = "0.3.9"
+version = "0.3.10"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "703d5c7ef118737c72f1af64ad2f6f8c5e1921f818cdcb97b8fe6fc69bf66214"
+checksum = "3a219298ac11a56ea9a6d2120044824d6f01aeb034955e7af7bc16858527deea"
 
 [[package]]
 name = "slab"
@@ -1204,9 +1184,9 @@ checksum = "0c790de23124f9ab44544d7ac05d60440adc586479ce501c1d6d7da3cd8c9cf5"
 
 [[package]]
 name = "smallvec"
-version = "1.15.1"
+version = "1.15.2"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "67b1b7a3b5fe4f1376887184045fcf45c69e92af734b7aaddc05fb777b6fbd03"
+checksum = "8ed6a63f02c8539c91a8685a86f4099661ba3da017932f6ebbea6de3f0fa7c90"
 
 [[package]]
 name = "strsim"
@@ -1215,7 +1195,7 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "7da8b5736845d9f2fcb837ea5d9e2628564b3b043a70948a3f0b778838c5fb4f"
 
 [[package]]
-name = "symbol-check"
+name = "symcheck"
 version = "0.1.0"
 dependencies = [
  "assert_cmd",
@@ -1229,9 +1209,20 @@ dependencies = [
 
 [[package]]
 name = "syn"
-version = "2.0.117"
+version = "2.0.119"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "872831b642d1a07999a962a351ed35b955ea2cfc8f3862091e2a240a84f17297"
+dependencies = [
+ "proc-macro2",
+ "quote",
+ "unicode-ident",
+]
+
+[[package]]
+name = "syn"
+version = "3.0.3"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "e665b8803e7b1d2a727f4023456bbbbe74da67099c585258af0ad9c5013b9b99"
+checksum = "53e9bae58849f64dfa4f5d5ae372c8341f7305f82a3868709269343628b659a3"
 dependencies = [
  "proc-macro2",
  "quote",
@@ -1269,9 +1260,9 @@ dependencies = [
 
 [[package]]
 name = "twox-hash"
-version = "2.1.2"
+version = "2.1.3"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "9ea3136b675547379c4bd395ca6b938e5ad3c3d20fad76e7fe85f9e0d011419c"
+checksum = "8464ec13c3691491391d9fce00f6416c9a48e46972f72d7865688be2080192c9"
 
 [[package]]
 name = "unicode-ident"
@@ -1285,12 +1276,6 @@ version = "0.2.2"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "b4ac048d71ede7ee76d585517add45da530660ef4390e49b098733c6e897f254"
 
-[[package]]
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-version = "0.2.6"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "ebc1c04c71510c7f702b52b7c350734c9ff1295c464a03335b00bb84fc54f853"
-
 [[package]]
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 version = "0.5.2"
@@ -1299,9 +1284,9 @@ checksum = "81e544489bf3d8ef66c953931f56617f423cd4b5494be343d9b9d3dda037b9a3"
 
 [[package]]
 name = "unty-next"
-version = "0.1.1"
+version = "0.1.2"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "9fa66022bbd1ab992fad72bdedcfd07a0023b6f5ecc83d50121e39e3a3caed41"
+checksum = "16062d030850f35054e37746427b9febb74a2f24c9c6dd6fa2d0c13c5f53221e"
 
 [[package]]
 name = "update-api-list"
@@ -1324,7 +1309,6 @@ checksum = "06abde3611657adf66d383f00b093d7faecc7fa57071cce2578660c9f1010821"
 name = "util"
 version = "0.1.0"
 dependencies = [
- "cfg-if",
  "libm 0.2.16",
  "libm-macros",
  "libm-test",
@@ -1351,29 +1335,11 @@ dependencies = [
  "winapi-util",
 ]
 
-[[package]]
-name = "wasip2"
-version = "1.0.3+wasi-0.2.9"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "20064672db26d7cdc89c7798c48a0fdfac8213434a1186e5ef29fd560ae223d6"
-dependencies = [
- "wit-bindgen 0.57.1",
-]
-
-[[package]]
-name = "wasip3"
-version = "0.4.0+wasi-0.3.0-rc-2026-01-06"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "5428f8bf88ea5ddc08faddef2ac4a67e390b88186c703ce6dbd955e1c145aca5"
-dependencies = [
- "wit-bindgen 0.51.0",
-]
-
 [[package]]
 name = "wasm-bindgen"
-version = "0.2.120"
+version = "0.2.127"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "df52b6d9b87e0c74c9edfa1eb2d9bf85e5d63515474513aa50fa181b3c4f5db1"
+checksum = "1b70935747edd64d89de3efa29d73789b806c15798f8e7dca4d8ac356b50ce70"
 dependencies = [
  "cfg-if",
  "once_cell",
@@ -1384,9 +1350,9 @@ dependencies = [
 
 [[package]]
 name = "wasm-bindgen-macro"
-version = "0.2.120"
+version = "0.2.127"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "78b1041f495fb322e64aca85f5756b2172e35cd459376e67f2a6c9dffcedb103"
+checksum = "77775f8f3f7217702089053b94958f8f54061a3f663417df76e19cbdcca29bc1"
 dependencies = [
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  "wasm-bindgen-macro-support",
@@ -1394,74 +1360,40 @@ dependencies = [
 
 [[package]]
 name = "wasm-bindgen-macro-support"
-version = "0.2.120"
+version = "0.2.127"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "9dcd0ff20416988a18ac686d4d4d0f6aae9ebf08a389ff5d29012b05af2a1b41"
+checksum = "e11d33f857dc2fb11b8bc75aee111aa9cbeb12cd9f25efd3d4c2a3dd4e235284"
 dependencies = [
  "bumpalo",
  "proc-macro2",
  "quote",
- "syn",
+ "syn 2.0.119",
  "wasm-bindgen-shared",
 ]
 
 [[package]]
 name = "wasm-bindgen-shared"
-version = "0.2.120"
+version = "0.2.127"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "49757b3c82ebf16c57d69365a142940b384176c24df52a087fb748e2085359ea"
+checksum = "7ef64dbcc55df09c7e5a46182d181c2cfa3e925f3da937ea764728b4bbb9dcbf"
 dependencies = [
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 ]
 
-[[package]]
-name = "wasm-encoder"
-version = "0.244.0"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "990065f2fe63003fe337b932cfb5e3b80e0b4d0f5ff650e6985b1048f62c8319"
-dependencies = [
- "leb128fmt",
- "wasmparser 0.244.0",
-]
-
-[[package]]
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-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "bb0e353e6a2fbdc176932bbaab493762eb1255a7900fe0fea1a2f96c296cc909"
-dependencies = [
- "anyhow",
- "indexmap",
- "wasm-encoder",
- "wasmparser 0.244.0",
-]
-
 [[package]]
 name = "wasmparser"
-version = "0.244.0"
+version = "0.255.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "47b807c72e1bac69382b3a6fb3dbe8ea4c0ed87ff5629b8685ae6b9a611028fe"
-dependencies = [
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- "hashbrown 0.15.5",
- "indexmap",
- "semver",
-]
-
-[[package]]
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-version = "0.247.0"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "8e6fb4c2bee46c5ea4d40f8cdb5c131725cd976718ec56f1c8e82fbde5fa2a80"
+checksum = "e8e329ef4b5d46e73b91d3ac6924417cad55a8cbbf869c199283383427c3320b"
 dependencies = [
  "bitflags",
 ]
 
 [[package]]
 name = "web-sys"
-version = "0.3.97"
+version = "0.3.104"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "2eadbac71025cd7b0834f20d1fe8472e8495821b4e9801eb0a60bd1f19827602"
+checksum = "c435338968042f4f59a557f690a253676d47ce13ceb55d70100e7facf6620a30"
 dependencies = [
  "js-sys",
  "wasm-bindgen",
@@ -1523,100 +1455,6 @@ dependencies = [
  "windows-link",
 ]
 
-[[package]]
-name = "wit-bindgen"
-version = "0.51.0"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "d7249219f66ced02969388cf2bb044a09756a083d0fab1e566056b04d9fbcaa5"
-dependencies = [
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-]
-
-[[package]]
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-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "1ebf944e87a7c253233ad6766e082e3cd714b5d03812acc24c318f549614536e"
-
-[[package]]
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-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "ea61de684c3ea68cb082b7a88508a8b27fcc8b797d738bfc99a82facf1d752dc"
-dependencies = [
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- "heck",
- "wit-parser",
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-
-[[package]]
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- "syn",
- "wasm-metadata",
- "wit-bindgen-core",
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-
-[[package]]
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-
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-source = "registry+https://github.com/rust-lang/crates.io-index"
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- "wasmparser 0.244.0",
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-
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- "indexmap",
- "log",
- "semver",
- "serde",
- "serde_derive",
- "serde_json",
- "unicode-xid",
- "wasmparser 0.244.0",
-]
-
 [[package]]
 name = "yansi"
 version = "1.0.1"
@@ -1625,26 +1463,26 @@ checksum = "cfe53a6657fd280eaa890a3bc59152892ffa3e30101319d168b781ed6529b049"
 
 [[package]]
 name = "zerocopy"
-version = "0.8.48"
+version = "0.8.56"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "eed437bf9d6692032087e337407a86f04cd8d6a16a37199ed57949d415bd68e9"
+checksum = "556764e583adb45a9f8d413c2a147fa7e8d821e48e12b14fd560b607998b75eb"
 dependencies = [
  "zerocopy-derive",
 ]
 
 [[package]]
 name = "zerocopy-derive"
-version = "0.8.48"
+version = "0.8.56"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "70e3cd084b1788766f53af483dd21f93881ff30d7320490ec3ef7526d203bad4"
+checksum = "f2ab42fc20575779bd240faa45f94a74256f755c0fa9e89f0ede20d91d0cdfc1"
 dependencies = [
  "proc-macro2",
  "quote",
- "syn",
+ "syn 2.0.119",
 ]
 
 [[package]]
 name = "zmij"
-version = "1.0.21"
+version = "1.0.23"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "b8848ee67ecc8aedbaf3e4122217aff892639231befc6a1b58d29fff4c2cabaa"
+checksum = "29666d0abbfad1e3dc4dcf6144730dd3a3ab225bbbdac83319345b1b44ccfc1b"
diff --git a/library/compiler-builtins/Cargo.toml b/library/compiler-builtins/Cargo.toml
index ceff63ac930a2..423adfbcbd02c 100644
--- a/library/compiler-builtins/Cargo.toml
+++ b/library/compiler-builtins/Cargo.toml
@@ -7,7 +7,7 @@ members = [
     "crates/libm-macros",
     "crates/musl-math-sys",
     "crates/panic-handler",
-    "crates/symbol-check",
+    "crates/symcheck",
     "crates/update-api-list",
     "crates/util",
     "libm",
@@ -39,7 +39,6 @@ anyhow = "1.0.101"
 api-list-common = { path = "crates/api-list-common" }
 assert_cmd = "2.1.2"
 cc = "1.2.56"
-cfg-if = "1.0.4"
 compiler_builtins = { path = "builtins-shim", default-features = false }
 criterion = { version = "0.8.2", default-features = false, features = ["cargo_bench_support"] }
 getopts = "0.2.24"
@@ -55,7 +54,7 @@ libm-test = { path = "libm-test", default-features = false }
 libtest-mimic = "0.8.1"
 musl-math-sys = { path = "crates/musl-math-sys" }
 no-panic = "0.1.36"
-object = { version = "0.39.0", features = ["wasm"] }
+object = { version = "0.40.0", features = ["wasm"] }
 panic-handler = { path = "crates/panic-handler" }
 paste = "1.0.15"
 pretty_assertions = "1.4.1"
@@ -69,7 +68,7 @@ regex = "1.12.3"
 rug = { version = "1.28.1", default-features = false, features = ["float", "integer", "std"] }
 rustc_apfloat = "0.2.3"
 serde_json = "1.0.149"
-syn = "2.0.115"
+syn = "3.0.3"
 tempfile = "3.25.0"
 
 [profile.release]
diff --git a/library/compiler-builtins/builtins-test-intrinsics/Cargo.lock b/library/compiler-builtins/builtins-test-intrinsics/Cargo.lock
new file mode 100644
index 0000000000000..5f3754a2de305
--- /dev/null
+++ b/library/compiler-builtins/builtins-test-intrinsics/Cargo.lock
@@ -0,0 +1,71 @@
+# This file is automatically @generated by Cargo.
+# It is not intended for manual editing.
+version = 4
+
+[[package]]
+name = "builtins-test-intrinsics"
+version = "0.1.0"
+dependencies = [
+ "compiler_builtins",
+ "panic-handler",
+ "test",
+ "utest-cortex-m-qemu",
+ "utest-macros",
+]
+
+[[package]]
+name = "cc"
+version = "1.4.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "5d262e149917187838d5b42777c8253bcb64500067342904e7d429499a6f277e"
+dependencies = [
+ "find-msvc-tools",
+ "shlex",
+]
+
+[[package]]
+name = "compiler_builtins"
+version = "0.1.160"
+dependencies = [
+ "cc",
+]
+
+[[package]]
+name = "find-msvc-tools"
+version = "0.1.10"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "26b73573e6edcd2af0cdf47bd6cb58f0b3839491263c314eaad1ccf24430e1de"
+
+[[package]]
+name = "panic-handler"
+version = "0.1.0"
+
+[[package]]
+name = "sc"
+version = "0.2.7"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "010e18bd3bfd1d45a7e666b236c78720df0d9a7698ebaa9c1c559961eb60a38b"
+
+[[package]]
+name = "shlex"
+version = "2.0.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "f8fadd59c855ef2080decdef8ff161eb6661b86933c9d82e5ba29dc602a55aba"
+
+[[package]]
+name = "test"
+version = "0.1.0"
+source = "git+https://github.com/japaric/utest#e32073e2b078e3bee46001c13ae4c1acf368d762"
+
+[[package]]
+name = "utest-cortex-m-qemu"
+version = "0.1.0"
+source = "git+https://github.com/japaric/utest#e32073e2b078e3bee46001c13ae4c1acf368d762"
+dependencies = [
+ "sc",
+]
+
+[[package]]
+name = "utest-macros"
+version = "0.1.0"
+source = "git+https://github.com/japaric/utest#e32073e2b078e3bee46001c13ae4c1acf368d762"
diff --git a/library/compiler-builtins/builtins-test/src/lib.rs b/library/compiler-builtins/builtins-test/src/lib.rs
index 70478f5f6d745..56c04e551df9d 100644
--- a/library/compiler-builtins/builtins-test/src/lib.rs
+++ b/library/compiler-builtins/builtins-test/src/lib.rs
@@ -1,6 +1,6 @@
 //! This crate is for integration testing and fuzz testing of functions in `compiler-builtins`. This
 //! includes publicly documented intrinsics and some internal alternative implementation functions
-//! such as `usize_leading_zeros_riscv` (which are tested because they are configured for
+//! such as `usize_leading_zeros_condset` (which are tested because they are configured for
 //! architectures not tested by the CI).
 //!
 //! The general idea is to use a combination of edge case testing and randomized fuzz testing. The
diff --git a/library/compiler-builtins/builtins-test/tests/misc.rs b/library/compiler-builtins/builtins-test/tests/misc.rs
index 64a9d56f36b33..a637cb71189e5 100644
--- a/library/compiler-builtins/builtins-test/tests/misc.rs
+++ b/library/compiler-builtins/builtins-test/tests/misc.rs
@@ -65,7 +65,7 @@ fn fuzz_values() {
 
 #[test]
 fn leading_zeros() {
-    use compiler_builtins::int::leading_zeros::{leading_zeros_default, leading_zeros_riscv};
+    use compiler_builtins::int::leading_zeros::{leading_zeros_condset, leading_zeros_default};
     {
         use compiler_builtins::int::leading_zeros::__clzsi2;
         fuzz(N, |x: u32| {
@@ -75,7 +75,7 @@ fn leading_zeros() {
             let lz = x.leading_zeros() as usize;
             let lz0 = __clzsi2(x);
             let lz1 = leading_zeros_default(x);
-            let lz2 = leading_zeros_riscv(x);
+            let lz2 = leading_zeros_condset(x);
             if lz0 != lz {
                 panic!("__clzsi2({x}): std: {lz}, builtins: {lz0}");
             }
@@ -83,7 +83,7 @@ fn leading_zeros() {
                 panic!("leading_zeros_default({x}): std: {lz}, builtins: {lz1}");
             }
             if lz2 != lz {
-                panic!("leading_zeros_riscv({x}): std: {lz}, builtins: {lz2}");
+                panic!("leading_zeros_condset({x}): std: {lz}, builtins: {lz2}");
             }
         });
     }
@@ -97,7 +97,7 @@ fn leading_zeros() {
             let lz = x.leading_zeros() as usize;
             let lz0 = __clzdi2(x);
             let lz1 = leading_zeros_default(x);
-            let lz2 = leading_zeros_riscv(x);
+            let lz2 = leading_zeros_condset(x);
             if lz0 != lz {
                 panic!("__clzdi2({x}): std: {lz}, builtins: {lz0}");
             }
@@ -105,7 +105,7 @@ fn leading_zeros() {
                 panic!("leading_zeros_default({x}): std: {lz}, builtins: {lz1}");
             }
             if lz2 != lz {
-                panic!("leading_zeros_riscv({x}): std: {lz}, builtins: {lz2}");
+                panic!("leading_zeros_condset({x}): std: {lz}, builtins: {lz2}");
             }
         });
     }
diff --git a/library/compiler-builtins/ci/bench-icount.sh b/library/compiler-builtins/ci/bench-icount.sh
index cd36303ca316a..ac86453bceb18 100755
--- a/library/compiler-builtins/ci/bench-icount.sh
+++ b/library/compiler-builtins/ci/bench-icount.sh
@@ -13,6 +13,7 @@ fi
 # Print machine information
 uname -a
 lscpu || true
+rustc -Vv
 
 gungraun_home="gungraun-home"
 
diff --git a/library/compiler-builtins/ci/ci-util.py b/library/compiler-builtins/ci/ci-util.py
index f359c59797448..97f563dbd6230 100755
--- a/library/compiler-builtins/ci/ci-util.py
+++ b/library/compiler-builtins/ci/ci-util.py
@@ -229,12 +229,21 @@ def _init_change_list(self):
         assert len(parents) == 2, f"expected two-parent merge but got:\n{parents}"
         base = parents[0].strip()
         incoming = parents[1].strip()
-
         eprint(f"base: {base}, incoming: {incoming}")
+
+        merge_base = sp.check_output(
+            GIT + ["merge-base", base, incoming], text=True
+        ).strip()
+        eprint(f"merge base: {merge_base}")
+
         textlist = sp.check_output(
-            GIT + ["diff", base, incoming, "--name-only"], text=True
+            GIT + ["diff", merge_base, incoming, "--name-only"], text=True
         )
         self.changed = [Path(p) for p in textlist.splitlines()]
+        eprint("all changed: [")
+        for f in self.changed:
+            eprint(f"    {f},")
+        eprint("]")
 
     def is_pr(self) -> bool:
         """Check if we are looking at a PR rather than a push."""
@@ -304,7 +313,7 @@ def emit_workflow_output(self):
                 eprint("Skipping all extensive tests")
 
         changed = self.changed_routines()
-        eprint(f"Changed: {changed}")
+        eprint(f"changed routines: {changed}")
 
         matrix = []
         total_to_test = 0
diff --git a/library/compiler-builtins/ci/compiler-rt-patches/0001-compiler-rt-Disable-executable-stack-on-aeabi_u-read.patch b/library/compiler-builtins/ci/compiler-rt-patches/0001-compiler-rt-Disable-executable-stack-on-aeabi_u-read.patch
new file mode 100644
index 0000000000000..13f4bc31d08f7
--- /dev/null
+++ b/library/compiler-builtins/ci/compiler-rt-patches/0001-compiler-rt-Disable-executable-stack-on-aeabi_u-read.patch
@@ -0,0 +1,95 @@
+From 849c51e082b0958524246a0a880f46d468a55147 Mon Sep 17 00:00:00 2001
+From: Trevor Gross <tg@trevorgross.com>
+Date: Thu, 6 Aug 2026 09:08:27 -0400
+Subject: [PATCH] [compiler-rt] Disable executable stack on
+ `aeabi_u{read,write}*.S` (#214465)
+
+These were missing `NO_EXEC_STACK_DIRECTIVE` to add `.note.GNU-stack`;
+without it, a binary including any of these files will have the stack
+marked executable. Add the directive here, matching other similar files.
+
+Symtab diff before:
+
+$ clang compiler-rt/lib/builtins/arm/aeabi_uread4.S
+--target=arm-unknown-linux-gnueabi -c
+    $ llvm-readelf aeabi_uread4.o -S
+    There are 5 section headers, starting at offset 0xe4:
+
+    Section Headers:
+[Nr] Name Type Address Off Size ES Flg Lk Inf Al
+[ 0] NULL 00000000 000000 000000 00 0 0 0
+[ 1] .strtab STRTAB 00000000 0000a8 000039 00 0 0 1
+[ 2] .text PROGBITS 00000000 000034 000020 00 AX 0 0 4
+[ 3] .ARM.attributes ARM_ATTRIBUTES 00000000 000054 000022 00 0 0 1
+[ 4] .symtab SYMTAB 00000000 000078 000030 10 1 2 4
+
+After:
+
+$ clang compiler-rt/lib/builtins/arm/aeabi_uread4.S
+--target=arm-unknown-linux-gnueabi -c
+    $ llvm-readelf aeabi_uread4.o -S
+    There are 6 section headers, starting at offset 0xf4:
+
+    Section Headers:
+[Nr] Name Type Address Off Size ES Flg Lk Inf Al
+[ 0] NULL 00000000 000000 000000 00 0 0 0
+[ 1] .strtab STRTAB 00000000 0000a8 000049 00 0 0 1
+[ 2] .text PROGBITS 00000000 000034 000020 00 AX 0 0 4
+[ 3] .note.GNU-stack PROGBITS 00000000 000054 000000 00 0 0 1
+[ 4] .ARM.attributes ARM_ATTRIBUTES 00000000 000054 000022 00 0 0 1
+[ 5] .symtab SYMTAB 00000000 000078 000030 10 1 2 4
+
+Fixes: 39413af931a7 ("[Compiler-rt] Implement AEABI Unaligned Read/Write
+       Helpers in compiler-rt (#167913)")
+---
+
+Add this patch to avoid a symcheck failure until the LLVM update can work
+through.
+
+ compiler-rt/lib/builtins/arm/aeabi_uread4.S  | 1 +
+ compiler-rt/lib/builtins/arm/aeabi_uread8.S  | 2 ++
+ compiler-rt/lib/builtins/arm/aeabi_uwrite4.S | 2 ++
+ compiler-rt/lib/builtins/arm/aeabi_uwrite8.S | 2 ++
+ 4 files changed, 7 insertions(+)
+
+diff --git a/compiler-rt/lib/builtins/arm/aeabi_uread4.S b/compiler-rt/lib/builtins/arm/aeabi_uread4.S
+index 4a54890fdf83..05e476a17905 100644
+--- a/compiler-rt/lib/builtins/arm/aeabi_uread4.S
++++ b/compiler-rt/lib/builtins/arm/aeabi_uread4.S
+@@ -61,3 +61,4 @@ DEFINE_COMPILERRT_FUNCTION(__aeabi_uread4)
+ #endif
+ END_COMPILERRT_FUNCTION(__aeabi_uread4)
+
++NO_EXEC_STACK_DIRECTIVE
+diff --git a/compiler-rt/lib/builtins/arm/aeabi_uread8.S b/compiler-rt/lib/builtins/arm/aeabi_uread8.S
+index 32844b8b3c7e..0b12c48ae46f 100644
+--- a/compiler-rt/lib/builtins/arm/aeabi_uread8.S
++++ b/compiler-rt/lib/builtins/arm/aeabi_uread8.S
+@@ -98,3 +98,5 @@ DEFINE_COMPILERRT_FUNCTION(__aeabi_uread8)
+ #endif
+
+ END_COMPILERRT_FUNCTION(__aeabi_uread8)
++
++NO_EXEC_STACK_DIRECTIVE
+diff --git a/compiler-rt/lib/builtins/arm/aeabi_uwrite4.S b/compiler-rt/lib/builtins/arm/aeabi_uwrite4.S
+index 9f749695910b..7e9a0337b781 100644
+--- a/compiler-rt/lib/builtins/arm/aeabi_uwrite4.S
++++ b/compiler-rt/lib/builtins/arm/aeabi_uwrite4.S
+@@ -33,3 +33,5 @@ DEFINE_COMPILERRT_FUNCTION(__aeabi_uwrite4)
+ #endif
+         bx      lr
+ END_COMPILERRT_FUNCTION(__aeabi_uwrite4)
++
++NO_EXEC_STACK_DIRECTIVE
+diff --git a/compiler-rt/lib/builtins/arm/aeabi_uwrite8.S b/compiler-rt/lib/builtins/arm/aeabi_uwrite8.S
+index 8188032fc3bd..763f42ff7ed0 100644
+--- a/compiler-rt/lib/builtins/arm/aeabi_uwrite8.S
++++ b/compiler-rt/lib/builtins/arm/aeabi_uwrite8.S
+@@ -49,3 +49,5 @@ DEFINE_COMPILERRT_FUNCTION(__aeabi_uwrite8)
+ #endif
+         bx      lr
+ END_COMPILERRT_FUNCTION(__aeabi_uwrite8)
++
++NO_EXEC_STACK_DIRECTIVE
+--
+2.50.1 (Apple Git-155)
diff --git a/library/compiler-builtins/ci/download-compiler-rt.sh b/library/compiler-builtins/ci/download-compiler-rt.sh
index 87b337d8255bb..55498c61d54b4 100755
--- a/library/compiler-builtins/ci/download-compiler-rt.sh
+++ b/library/compiler-builtins/ci/download-compiler-rt.sh
@@ -4,7 +4,13 @@
 
 set -eux
 
-rust_llvm_version=20.1-2025-02-13
+rust_llvm_version=23.1-2026-07-22
 
 curl -L --retry 3 -o code.tar.gz "https://github.com/rust-lang/llvm-project/archive/rustc/${rust_llvm_version}.tar.gz"
 tar xzf code.tar.gz --strip-components 1 llvm-project-rustc-${rust_llvm_version}/compiler-rt
+
+cd compiler-rt
+
+for p in ../ci/compiler-rt-patches/*; do
+    cat "$p" | patch -p 2
+done
diff --git a/library/compiler-builtins/ci/miri.sh b/library/compiler-builtins/ci/miri.sh
index 2751bf0dc49e1..498bbe3c47f00 100755
--- a/library/compiler-builtins/ci/miri.sh
+++ b/library/compiler-builtins/ci/miri.sh
@@ -1,9 +1,11 @@
 #!/bin/bash
 set -eux
 
+# We need to disable the randomness that Miri intentionally introduces when
+# performing floating-point operations
 # We need Tree Borrows as some of our raw pointer patterns are not
 # compatible with Stacked Borrows.
-export MIRIFLAGS="-Zmiri-tree-borrows"
+export MIRIFLAGS="-Zmiri-deterministic-floats -Zmiri-tree-borrows"
 
 # One target that sets `mem_unaligned` and one that does not,
 # and a big-endian target.
@@ -20,4 +22,10 @@ for target in "${targets[@]}"; do
         --no-default-features \
         --target "$target" \
         -- mem
+
+    # Run the `libm` tests as well, but not `libm-test` to avoid this taking
+    # too long.
+    cargo miri test \
+        --manifest-path libm/Cargo.toml \
+        --target "$target"
 done
diff --git a/library/compiler-builtins/ci/run-docker.sh b/library/compiler-builtins/ci/run-docker.sh
index a894677b59f90..08f20b934acd5 100755
--- a/library/compiler-builtins/ci/run-docker.sh
+++ b/library/compiler-builtins/ci/run-docker.sh
@@ -11,8 +11,6 @@ host_arch="$(uname -m | sed 's/arm64/aarch64/')"
 # calling docker, otherwise docker will create them but they will be owned
 # by root.
 mkdir -p target
-cargo generate-lockfile
-cargo generate-lockfile --manifest-path builtins-test-intrinsics/Cargo.toml
 
 run() {
     local target="$1"
diff --git a/library/compiler-builtins/ci/run.sh b/library/compiler-builtins/ci/run.sh
index 93c551dc52ec7..359bf3d945b9b 100755
--- a/library/compiler-builtins/ci/run.sh
+++ b/library/compiler-builtins/ci/run.sh
@@ -13,6 +13,12 @@ if [ -z "$target" ]; then
     target="$host_target"
 fi
 
+# Print machine information
+uname -a
+lscpu || true
+rustc -Vv
+cc -v || true
+
 if [ "${USING_CONTAINER_RUSTC:-}" = 1 ]; then
     # Install nonstandard components if we have control of the environment
     rustup target list --installed |
@@ -72,8 +78,8 @@ fi
 # Ensure there are no duplicate symbols or references to `core` when
 # `compiler-builtins` is built with various features. Symcheck invokes Cargo to
 # build with the arguments we provide it, then validates the built artifacts.
-SYMCHECK_TEST_TARGET="$target" cargo test -p symbol-check --release
-symcheck=(cargo run -p symbol-check --release)
+SYMCHECK_TEST_TARGET="$target" cargo test -p symcheck --release
+symcheck=(cargo run -p symcheck --release)
 symcheck+=(-- --build-and-check --target "$target")
 
 # Executable section checks are meaningless on no-std targets
@@ -145,10 +151,6 @@ case "$target" in
 
     # We can build musl on MinGW but running tests gets a stack overflow
     *windows-gnu*) ;;
-    # FIXME(#309): LE PPC crashes calling the musl version of some functions. It
-    # seems like a qemu bug but should be investigated further at some point.
-    # See <https://github.com/rust-lang/libm/issues/309>.
-    *powerpc64le*) ;;
 
     # Everything else gets musl enabled
     *) mflags+=(--features libm-test/build-musl) ;;
@@ -184,7 +186,7 @@ if [ "${BUILD_ONLY:-}" = "1" ]; then
     echo "can't run tests on $target; skipping"
 else
     # symcheck tests need specific env setup, and is already tested above
-    mflags+=(--workspace --exclude symbol-check --target "$target")
+    mflags+=(--workspace --exclude symcheck --target "$target")
     cmd=("${test_runner[@]}" "${mflags[@]}")
 
     # Test once without intrinsics
diff --git a/library/compiler-builtins/compiler-builtins/src/arm.rs b/library/compiler-builtins/compiler-builtins/src/arm.rs
index f26fce2d912b6..0c15b37df1dc1 100644
--- a/library/compiler-builtins/compiler-builtins/src/arm.rs
+++ b/library/compiler-builtins/compiler-builtins/src/arm.rs
@@ -84,11 +84,7 @@ intrinsics! {
     ///
     /// Usual `memcpy` requirements apply.
     #[cfg(not(target_vendor = "apple"))]
-    pub unsafe extern "aapcs" fn __aeabi_memcpy(
-        dst: *mut core::ffi::c_void,
-        src: *const core::ffi::c_void,
-        n: usize
-    ) {
+    pub unsafe extern "aapcs" fn __aeabi_memcpy(dst: *mut u8, src: *const u8, n: usize) {
         // SAFETY: memcpy preconditions apply.
         unsafe { crate::mem::memcpy(dst, src, n) };
     }
@@ -100,11 +96,7 @@ intrinsics! {
     /// Usual `memcpy` requirements apply. Additionally, `dest` and `src` must be aligned to
     /// four bytes.
     #[cfg(not(target_vendor = "apple"))]
-    pub unsafe extern "aapcs" fn __aeabi_memcpy4(
-        dst: *mut core::ffi::c_void,
-        src: *const core::ffi::c_void,
-        n: usize
-    ) {
+    pub unsafe extern "aapcs" fn __aeabi_memcpy4(dst: *mut u8, src: *const u8, n: usize) {
         // We are guaranteed 4-alignment, so accessing at u32 is okay.
         let mut dst = dst.cast::<u32>();
         let mut src = src.cast::<u32>();
@@ -129,7 +121,7 @@ intrinsics! {
         }
 
         // SAFETY: `dst` and `src` will still be valid for `n` bytes
-        unsafe { __aeabi_memcpy(dst.cast::<core::ffi::c_void>(), src.cast::<core::ffi::c_void>(), n) };
+        unsafe { __aeabi_memcpy(dst.cast::<u8>(), src.cast::<u8>(), n) };
     }
 
     /// `memcpy` for 8-byte alignment.
@@ -139,11 +131,7 @@ intrinsics! {
     /// Usual `memcpy` requirements apply. Additionally, `dest` and `src` must be aligned to
     /// eight bytes.
     #[cfg(not(target_vendor = "apple"))]
-    pub unsafe extern "aapcs" fn __aeabi_memcpy8(
-        dst: *mut core::ffi::c_void,
-        src: *const core::ffi::c_void,
-        n: usize
-    ) {
+    pub unsafe extern "aapcs" fn __aeabi_memcpy8(dst: *mut u8, src: *const u8, n: usize) {
         debug_assert!(dst.addr().is_multiple_of(8));
         debug_assert!(src.addr().is_multiple_of(8));
 
@@ -157,11 +145,7 @@ intrinsics! {
     ///
     /// Usual `memmove` requirements apply.
     #[cfg(not(target_vendor = "apple"))]
-    pub unsafe extern "aapcs" fn __aeabi_memmove(
-        dst: *mut core::ffi::c_void,
-        src: *const core::ffi::c_void,
-        n: usize
-    ) {
+    pub unsafe extern "aapcs" fn __aeabi_memmove(dst: *mut u8, src: *const u8, n: usize) {
         // SAFETY: memmove preconditions apply.
         unsafe { crate::mem::memmove(dst, src, n) };
     }
@@ -173,11 +157,7 @@ intrinsics! {
     /// Usual `memmove` requirements apply. Additionally, `dest` and `src` must be aligned to
     /// four bytes.
     #[cfg(not(any(target_vendor = "apple", target_env = "msvc")))]
-    pub unsafe extern "aapcs" fn __aeabi_memmove4(
-        dst: *mut core::ffi::c_void,
-        src: *const core::ffi::c_void,
-        n: usize
-    ) {
+    pub unsafe extern "aapcs" fn __aeabi_memmove4(dst: *mut u8, src: *const u8, n: usize) {
         debug_assert!(dst.addr().is_multiple_of(4));
         debug_assert!(src.addr().is_multiple_of(4));
 
@@ -192,11 +172,7 @@ intrinsics! {
     /// Usual `memmove` requirements apply. Additionally, `dst` and `src` must be aligned to
     /// eight bytes.
     #[cfg(not(any(target_vendor = "apple", target_env = "msvc")))]
-    pub unsafe extern "aapcs" fn __aeabi_memmove8(
-        dst: *mut core::ffi::c_void,
-        src: *const core::ffi::c_void,
-        n: usize
-    ) {
+    pub unsafe extern "aapcs" fn __aeabi_memmove8(dst: *mut u8, src: *const u8, n: usize) {
         debug_assert!(dst.addr().is_multiple_of(8));
         debug_assert!(src.addr().is_multiple_of(8));
 
@@ -210,11 +186,7 @@ intrinsics! {
     ///
     /// Usual `memset` requirements apply.
     #[cfg(not(target_vendor = "apple"))]
-    pub unsafe extern "aapcs" fn __aeabi_memset(
-        dst: *mut core::ffi::c_void,
-        n: usize,
-        c: i32
-    ) {
+    pub unsafe extern "aapcs" fn __aeabi_memset(dst: *mut u8, n: usize, c: i32) {
         // Note the different argument order
         // SAFETY: memset preconditions apply.
         unsafe { crate::mem::memset(dst, c, n) };
@@ -227,11 +199,7 @@ intrinsics! {
     /// Usual `memset` requirements apply. Additionally, `dest` and `src` must be aligned to
     /// four bytes.
     #[cfg(not(target_vendor = "apple"))]
-    pub unsafe extern "aapcs" fn __aeabi_memset4(
-        dst: *mut core::ffi::c_void,
-        n: usize,
-        c: i32
-    ) {
+    pub unsafe extern "aapcs" fn __aeabi_memset4(dst: *mut u8, n: usize, c: i32) {
         let mut dst = dst.cast::<u32>();
         debug_assert!(dst.is_aligned());
         let mut n = n;
@@ -254,7 +222,7 @@ intrinsics! {
         }
 
         // SAFETY: `dst` will still be valid for `n` bytes
-        unsafe { __aeabi_memset(dst.cast::<core::ffi::c_void>(), n, byte as i32) };
+        unsafe { __aeabi_memset(dst.cast::<u8>(), n, byte as i32) };
     }
 
     /// `memset` for 8-byte alignment.
@@ -264,11 +232,7 @@ intrinsics! {
     /// Usual `memset` requirements apply. Additionally, `dst` and `src` must be aligned to
     /// eight bytes.
     #[cfg(not(target_vendor = "apple"))]
-    pub unsafe extern "aapcs" fn __aeabi_memset8(
-        dst: *mut core::ffi::c_void,
-        n: usize,
-        c: i32
-    ) {
+    pub unsafe extern "aapcs" fn __aeabi_memset8(dst: *mut u8, n: usize, c: i32) {
         debug_assert!(dst.addr().is_multiple_of(8));
 
         // SAFETY: memset preconditions apply, less strict alignment.
@@ -281,7 +245,7 @@ intrinsics! {
     ///
     /// Usual `memclr` requirements apply.
     #[cfg(not(target_vendor = "apple"))]
-    pub unsafe extern "aapcs" fn __aeabi_memclr(dst: *mut core::ffi::c_void, n: usize) {
+    pub unsafe extern "aapcs" fn __aeabi_memclr(dst: *mut u8, n: usize) {
         // SAFETY: memclr preconditions apply, less strict alignment.
         unsafe { __aeabi_memset(dst, n, 0) };
     }
@@ -293,7 +257,7 @@ intrinsics! {
     /// Usual `memclr` requirements apply. Additionally, `dest` and `src` must be aligned to
     /// four bytes.
     #[cfg(not(any(target_vendor = "apple", target_env = "msvc")))]
-    pub unsafe extern "aapcs" fn __aeabi_memclr4(dst: *mut core::ffi::c_void, n: usize) {
+    pub unsafe extern "aapcs" fn __aeabi_memclr4(dst: *mut u8, n: usize) {
         debug_assert!(dst.addr().is_multiple_of(4));
 
         // SAFETY: memclr preconditions apply, less strict alignment.
@@ -307,7 +271,7 @@ intrinsics! {
     /// Usual `memclr` requirements apply. Additionally, `dst` and `src` must be aligned to
     /// eight bytes.
     #[cfg(not(any(target_vendor = "apple", target_env = "msvc")))]
-    pub unsafe extern "aapcs" fn __aeabi_memclr8(dst: *mut core::ffi::c_void, n: usize) {
+    pub unsafe extern "aapcs" fn __aeabi_memclr8(dst: *mut u8, n: usize) {
         debug_assert!(dst.addr().is_multiple_of(8));
 
         // SAFETY: memclr preconditions apply, less strict alignment.
diff --git a/library/compiler-builtins/compiler-builtins/src/float/cmp.rs b/library/compiler-builtins/compiler-builtins/src/float/cmp.rs
index a59365a2bdb8b..243c9c767f61b 100644
--- a/library/compiler-builtins/compiler-builtins/src/float/cmp.rs
+++ b/library/compiler-builtins/compiler-builtins/src/float/cmp.rs
@@ -1,6 +1,6 @@
 #![allow(unreachable_code)]
 
-use crate::support::{Float, MinInt, cfg_if};
+use crate::support::{Float, MinInt, cfg_select_nofmt};
 
 // These definitions should be consistent with LLVM's definition from `getCmpLibcallReturnType`,
 // compiler-rt's definitions [1], GCC's `CMPtype` [2], and `libgcc`. To find the definitions
@@ -12,15 +12,17 @@ use crate::support::{Float, MinInt, cfg_if};
 //
 // [1]: https://github.com/llvm/llvm-project/blob/0cf3c437c18ed27d9663d87804a9a15ff6874af2/compiler-rt/lib/builtins/fp_compare_impl.inc#L11-L27
 // [2]: https://gcc.gnu.org/onlinedocs/gccint/Soft-float-library-routines.html#Comparison-functions-1
-cfg_if! {
-    if #[cfg(any(target_arch = "aarch64", target_arch = "arm64ec", target_family = "wasm"))] {
+cfg_select_nofmt! {
+    any(target_arch = "aarch64", target_arch = "arm64ec", target_family = "wasm") => {
         // Aarch64 uses `int` rather than a pointer-sized value.
         // `getCmpLibcallReturnType` for WASM is always set to i32.
         pub type CmpResult = i32;
-    } else if #[cfg(target_arch = "avr")] {
+    }
+    target_arch = "avr" => {
         // AVR uses a single byte.
         pub type CmpResult = i8;
-    } else {
+    }
+    _ => {
         // The default is word-sized. In LLVM's compiler-rt, this is done by using `long long` on
         // LLP64 ABIs and `long` on everything else.
         pub type CmpResult = isize;
diff --git a/library/compiler-builtins/compiler-builtins/src/hexagon.rs b/library/compiler-builtins/compiler-builtins/src/hexagon.rs
index 46062fc3700d8..551186b1db861 100644
--- a/library/compiler-builtins/compiler-builtins/src/hexagon.rs
+++ b/library/compiler-builtins/compiler-builtins/src/hexagon.rs
@@ -44,69 +44,34 @@ intrinsics! {
     }
 }
 
-global_asm!(include_str!("hexagon/func_macro.s"), options(raw));
-
+// All hexagon assembly must live in ONE `global_asm!` invocation, and
+// `func_macro.s` must come first.
 global_asm!(
+    include_str!("hexagon/func_macro.s"),
     include_str!("hexagon/common_entry_exit_abi1.s"),
-    options(raw)
-);
-
-global_asm!(
     include_str!("hexagon/common_entry_exit_abi2.s"),
-    options(raw)
-);
-
-global_asm!(
     include_str!("hexagon/common_entry_exit_legacy.s"),
-    options(raw)
-);
-
-global_asm!(include_str!("hexagon/dfaddsub.s"), options(raw));
-
-global_asm!(include_str!("hexagon/dfdiv.s"), options(raw));
-
-global_asm!(include_str!("hexagon/dffma.s"), options(raw));
-
-global_asm!(include_str!("hexagon/dfminmax.s"), options(raw));
-
-global_asm!(include_str!("hexagon/dfmul.s"), options(raw));
-
-global_asm!(include_str!("hexagon/dfsqrt.s"), options(raw));
-
-global_asm!(include_str!("hexagon/divdi3.s"), options(raw));
-
-global_asm!(include_str!("hexagon/divsi3.s"), options(raw));
-
-global_asm!(include_str!("hexagon/fastmath2_dlib_asm.s"), options(raw));
-
-global_asm!(include_str!("hexagon/fastmath2_ldlib_asm.s"), options(raw));
-
-global_asm!(
+    include_str!("hexagon/dfaddsub.s"),
+    include_str!("hexagon/dfdiv.s"),
+    include_str!("hexagon/dffma.s"),
+    include_str!("hexagon/dfminmax.s"),
+    include_str!("hexagon/dfmul.s"),
+    include_str!("hexagon/dfsqrt.s"),
+    include_str!("hexagon/divdi3.s"),
+    include_str!("hexagon/divsi3.s"),
+    include_str!("hexagon/fastmath2_dlib_asm.s"),
+    include_str!("hexagon/fastmath2_ldlib_asm.s"),
     include_str!("hexagon/memcpy_forward_vp4cp4n2.s"),
-    options(raw)
-);
-
-global_asm!(
     include_str!("hexagon/memcpy_likely_aligned.s"),
+    include_str!("hexagon/moddi3.s"),
+    include_str!("hexagon/modsi3.s"),
+    include_str!("hexagon/sfdiv_opt.s"),
+    include_str!("hexagon/sfsqrt_opt.s"),
+    include_str!("hexagon/udivdi3.s"),
+    include_str!("hexagon/udivmoddi4.s"),
+    include_str!("hexagon/udivmodsi4.s"),
+    include_str!("hexagon/udivsi3.s"),
+    include_str!("hexagon/umoddi3.s"),
+    include_str!("hexagon/umodsi3.s"),
     options(raw)
 );
-
-global_asm!(include_str!("hexagon/moddi3.s"), options(raw));
-
-global_asm!(include_str!("hexagon/modsi3.s"), options(raw));
-
-global_asm!(include_str!("hexagon/sfdiv_opt.s"), options(raw));
-
-global_asm!(include_str!("hexagon/sfsqrt_opt.s"), options(raw));
-
-global_asm!(include_str!("hexagon/udivdi3.s"), options(raw));
-
-global_asm!(include_str!("hexagon/udivmoddi4.s"), options(raw));
-
-global_asm!(include_str!("hexagon/udivmodsi4.s"), options(raw));
-
-global_asm!(include_str!("hexagon/udivsi3.s"), options(raw));
-
-global_asm!(include_str!("hexagon/umoddi3.s"), options(raw));
-
-global_asm!(include_str!("hexagon/umodsi3.s"), options(raw));
diff --git a/library/compiler-builtins/compiler-builtins/src/hexagon/dffma.s b/library/compiler-builtins/compiler-builtins/src/hexagon/dffma.s
index 6cd1f1b79f87a..b57ed17dc1fd2 100644
--- a/library/compiler-builtins/compiler-builtins/src/hexagon/dffma.s
+++ b/library/compiler-builtins/compiler-builtins/src/hexagon/dffma.s
@@ -338,10 +338,8 @@ __hexagon_fmadf5:
  {
   p0 = !cmp.eq(r2,#1)
   p0 = !cmp.eq(r3,#2)
- }
- {
-  p0 = dfcmp.eq(r9:8,r9:8)
   if (p0.new) r11:10 = r9:8
+  p0 = dfcmp.eq(r9:8,r9:8)
  }
  {
   r1:0 = insert(r11:10,#63,#0)
diff --git a/library/compiler-builtins/compiler-builtins/src/int/leading_zeros.rs b/library/compiler-builtins/compiler-builtins/src/int/leading_zeros.rs
index 3b920ecff6b20..c4d2569b3ab4e 100644
--- a/library/compiler-builtins/compiler-builtins/src/int/leading_zeros.rs
+++ b/library/compiler-builtins/compiler-builtins/src/int/leading_zeros.rs
@@ -4,9 +4,9 @@
 // Compilers will insert the check for zero in cases where it is needed.
 
 #[cfg(feature = "unstable-public-internals")]
-pub use implementation::{leading_zeros_default, leading_zeros_riscv};
+pub use implementation::{leading_zeros_condset, leading_zeros_default};
 #[cfg(not(feature = "unstable-public-internals"))]
-pub(crate) use implementation::{leading_zeros_default, leading_zeros_riscv};
+pub(crate) use implementation::{leading_zeros_condset, leading_zeros_default};
 
 mod implementation {
     use crate::support::{CastFrom, Int};
@@ -82,14 +82,15 @@ mod implementation {
         // execution effects. Changing to using a LUT and branching is risky for smaller cores.
     }
 
-    // The above method does not compile well on RISC-V (because of the lack of predicated
-    // instructions), producing code with many branches or using an excessively long
-    // branchless solution. This method takes advantage of the set-if-less-than instruction on
-    // RISC-V that allows `(x >= power-of-two) as usize` to be branchless.
+    // The above method does not compile well on RISC-V and LoongArch (because of the lack
+    // of predicated instructions), producing code with many branches or using an
+    // excessively long branchless solution. This method takes advantage of the
+    // set-if-less-than instruction on RISC-V and LoongArch that allows
+    // `(x >= power-of-two) as usize` to be branchless.
 
     /// Returns the number of leading binary zeros in `x`.
     #[allow(dead_code)]
-    pub fn leading_zeros_riscv<I: Int>(x: I) -> usize
+    pub fn leading_zeros_condset<I: Int>(x: I) -> usize
     where
         usize: CastFrom<I>,
     {
@@ -99,7 +100,7 @@ mod implementation {
         // a temporary
         let mut t: u32;
 
-        // RISC-V does not have a set-if-greater-than-or-equal instruction and
+        // RISC-V and LoongArch do not have a set-if-greater-than-or-equal instruction and
         // `(x >= power-of-two) as usize` will get compiled into two instructions, but this is
         // still the most optimal method. A conditional set can only be turned into a single
         // immediate instruction if `x` is compared with an immediate `imm` (that can fit into
@@ -146,8 +147,9 @@ mod implementation {
 intrinsics! {
     /// Returns the number of leading binary zeros in `x`
     pub extern "C" fn __clzsi2(x: u32) -> usize {
-        if cfg!(any(target_arch = "riscv32", target_arch = "riscv64")) {
-            leading_zeros_riscv(x)
+        if cfg!(any(target_arch = "loongarch32", target_arch = "loongarch64",
+                    target_arch = "riscv32", target_arch = "riscv64")) {
+            leading_zeros_condset(x)
         } else {
             leading_zeros_default(x)
         }
@@ -155,8 +157,9 @@ intrinsics! {
 
     /// Returns the number of leading binary zeros in `x`
     pub extern "C" fn __clzdi2(x: u64) -> usize {
-        if cfg!(any(target_arch = "riscv32", target_arch = "riscv64")) {
-            leading_zeros_riscv(x)
+        if cfg!(any(target_arch = "loongarch32", target_arch = "loongarch64",
+                    target_arch = "riscv32", target_arch = "riscv64")) {
+            leading_zeros_condset(x)
         } else {
             leading_zeros_default(x)
         }
diff --git a/library/compiler-builtins/compiler-builtins/src/int/specialized_div_rem/mod.rs b/library/compiler-builtins/compiler-builtins/src/int/specialized_div_rem/mod.rs
index 902c191d65285..e5324cdbd941e 100644
--- a/library/compiler-builtins/compiler-builtins/src/int/specialized_div_rem/mod.rs
+++ b/library/compiler-builtins/compiler-builtins/src/int/specialized_div_rem/mod.rs
@@ -97,6 +97,13 @@ const USE_LZ: bool = {
         // The 'Zbb' Basic Bit-Manipulation extension on RISC-V
         // determines if a CLZ assembly instruction exists
         cfg!(target_feature = "zbb")
+    } else if cfg!(any(
+        target_arch = "loongarch32",
+        target_arch = "loongarch64"
+    )) {
+        // The '32s' 32-bit standard feature on LoongArch
+        // determines if a CLZ assembly instruction exists
+        cfg!(target_feature = "32s")
     } else {
         // All other common targets Rust supports should have CLZ instructions
         true
diff --git a/library/compiler-builtins/compiler-builtins/src/lib.rs b/library/compiler-builtins/compiler-builtins/src/lib.rs
index 6bde5195e8af4..829475dcd42e2 100644
--- a/library/compiler-builtins/compiler-builtins/src/lib.rs
+++ b/library/compiler-builtins/compiler-builtins/src/lib.rs
@@ -1,5 +1,8 @@
 #![cfg_attr(feature = "compiler-builtins", compiler_builtins)]
-#![cfg_attr(all(target_family = "wasm"), feature(wasm_numeric_instr))]
+#![no_builtins]
+#![no_std]
+//
+#![feature(abi_custom)]
 #![feature(abi_unadjusted)]
 #![feature(asm_experimental_arch)]
 #![feature(cfg_target_has_atomic)]
@@ -11,8 +14,8 @@
 #![feature(rustc_attrs)]
 #![cfg_attr(f16_enabled, feature(f16))]
 #![cfg_attr(f128_enabled, feature(f128))]
-#![no_builtins]
-#![no_std]
+#![cfg_attr(all(target_family = "wasm"), feature(wasm_numeric_instr))]
+//
 #![allow(unstable_name_collisions)] // FIXME(float_bits_const): remove when stable
 #![allow(unused_features)]
 #![allow(internal_features)]
@@ -20,9 +23,6 @@
 #![allow(clippy::manual_swap)]
 // Support compiling on both stage0 and stage1 which may differ in supported stable features.
 #![allow(stable_features)]
-// By default, disallow this as it is forbidden in edition 2024. There is a lot of unsafe code to
-// be migrated, however, so exceptions exist.
-#![warn(unsafe_op_in_unsafe_fn)]
 
 // We disable #[no_mangle] for tests so that we can verify the test results
 // against the native compiler-rt implementations of the builtins.
diff --git a/library/compiler-builtins/compiler-builtins/src/mem/mod.rs b/library/compiler-builtins/compiler-builtins/src/mem/mod.rs
index ef0f4da228e96..e3c701892b671 100644
--- a/library/compiler-builtins/compiler-builtins/src/mem/mod.rs
+++ b/library/compiler-builtins/compiler-builtins/src/mem/mod.rs
@@ -2,6 +2,8 @@
 #![allow(clippy::style)]
 // FIXME(e2024): this eventually needs to be removed.
 #![allow(unsafe_op_in_unsafe_fn)]
+// FIXME(bench): remove when the benchmark rustc version is updated
+#![allow(unknown_lints)]
 
 // memcpy/memmove/memset have optimized implementations on some architectures
 #[cfg_attr(all(feature = "arch", target_arch = "x86_64"), path = "x86_64.rs")]
@@ -9,57 +11,42 @@ mod impls;
 
 intrinsics! {
     #[mem_builtin]
-    pub unsafe extern "C" fn memcpy(
-        dest: *mut core::ffi::c_void,
-        src: *const core::ffi::c_void,
-        n: usize
-    ) -> *mut core::ffi::c_void {
-        impls::copy_forward(dest.cast(), src.cast(), n);
+    #[allow(suspicious_runtime_symbol_definitions)]
+    pub unsafe extern "C" fn memcpy(dest: *mut u8, src: *const u8, n: usize) -> *mut u8 {
+        impls::copy_forward(dest, src, n);
         dest
     }
 
     #[mem_builtin]
-    pub unsafe extern "C" fn memmove(
-        dest: *mut core::ffi::c_void,
-        src: *const core::ffi::c_void,
-        n: usize
-    ) -> *mut core::ffi::c_void {
+    #[allow(suspicious_runtime_symbol_definitions)]
+    pub unsafe extern "C" fn memmove(dest: *mut u8, src: *const u8, n: usize) -> *mut u8 {
         let delta = (dest as usize).wrapping_sub(src as usize);
         if delta >= n {
             // We can copy forwards because either dest is far enough ahead of src,
             // or src is ahead of dest (and delta overflowed).
-            impls::copy_forward(dest.cast(), src.cast(), n);
+            impls::copy_forward(dest, src, n);
         } else {
-            impls::copy_backward(dest.cast(), src.cast(), n);
+            impls::copy_backward(dest, src, n);
         }
         dest
     }
 
     #[mem_builtin]
-    pub unsafe extern "C" fn memset(
-        s: *mut core::ffi::c_void,
-        c: core::ffi::c_int,
-        n: usize
-    ) -> *mut core::ffi::c_void {
-        impls::set_bytes(s.cast(), c as u8, n);
+    #[allow(suspicious_runtime_symbol_definitions)]
+    pub unsafe extern "C" fn memset(s: *mut u8, c: core::ffi::c_int, n: usize) -> *mut u8 {
+        impls::set_bytes(s, c as u8, n);
         s
     }
 
     #[mem_builtin]
-    pub unsafe extern "C" fn memcmp(
-        s1: *const core::ffi::c_void,
-        s2: *const core::ffi::c_void,
-        n: usize
-    ) -> core::ffi::c_int {
-        impls::compare_bytes(s1.cast(), s2.cast(), n)
+    #[allow(suspicious_runtime_symbol_definitions)]
+    pub unsafe extern "C" fn memcmp(s1: *const u8, s2: *const u8, n: usize) -> core::ffi::c_int {
+        impls::compare_bytes(s1, s2, n)
     }
 
     #[mem_builtin]
-    pub unsafe extern "C" fn bcmp(
-        s1: *const core::ffi::c_void,
-        s2: *const core::ffi::c_void,
-        n: usize
-    ) -> core::ffi::c_int {
+    #[allow(suspicious_runtime_symbol_definitions)]
+    pub unsafe extern "C" fn bcmp(s1: *const u8, s2: *const u8, n: usize) -> core::ffi::c_int {
         memcmp(s1, s2, n)
     }
 
diff --git a/library/compiler-builtins/crates/libm-macros/src/parse.rs b/library/compiler-builtins/crates/libm-macros/src/parse.rs
index 97067b876bda6..87add92996ccc 100644
--- a/library/compiler-builtins/crates/libm-macros/src/parse.rs
+++ b/library/compiler-builtins/crates/libm-macros/src/parse.rs
@@ -181,7 +181,6 @@ fn extract_fn_extra_field(expr: Expr) -> syn::Result<BTreeMap<Ident, Expr>> {
         let Arm {
             attrs,
             pat,
-            guard,
             fat_arrow_token: _,
             body,
             comma: _,
@@ -190,15 +189,15 @@ fn extract_fn_extra_field(expr: Expr) -> syn::Result<BTreeMap<Ident, Expr>> {
         expect_empty_attrs(&attrs)?;
 
         let keys = match pat {
+            syn::Pat::Ident(id) => Parser::parse2(parse_ident_pat, id.into_token_stream())?,
+            syn::Pat::Or(or) => Parser::parse2(parse_ident_pat, or.into_token_stream())?,
             syn::Pat::Wild(w) => vec![Ident::new("_", w.span())],
-            _ => Parser::parse2(parse_ident_pat, pat.into_token_stream())?,
+            _ => {
+                let e = syn::Error::new(pat.span(), "unsupported pattern type");
+                return Err(e);
+            }
         };
 
-        if let Some(guard) = guard {
-            let e = syn::Error::new(guard.0.span(), "no guards allowed in this position");
-            return Err(e);
-        }
-
         for key in keys {
             let inserted = res.insert(key.clone(), *body.clone());
             if inserted.is_some() {
diff --git a/library/compiler-builtins/crates/symbol-check/Cargo.toml b/library/compiler-builtins/crates/symcheck/Cargo.toml
similarity index 92%
rename from library/compiler-builtins/crates/symbol-check/Cargo.toml
rename to library/compiler-builtins/crates/symcheck/Cargo.toml
index 6d13f94888004..470cb61413c38 100644
--- a/library/compiler-builtins/crates/symbol-check/Cargo.toml
+++ b/library/compiler-builtins/crates/symcheck/Cargo.toml
@@ -1,5 +1,5 @@
 [package]
-name = "symbol-check"
+name = "symcheck"
 version = "0.1.0"
 edition = "2024"
 publish = false
diff --git a/library/compiler-builtins/crates/symbol-check/build.rs b/library/compiler-builtins/crates/symcheck/build.rs
similarity index 100%
rename from library/compiler-builtins/crates/symbol-check/build.rs
rename to library/compiler-builtins/crates/symcheck/build.rs
diff --git a/library/compiler-builtins/crates/symbol-check/src/main.rs b/library/compiler-builtins/crates/symcheck/src/main.rs
similarity index 59%
rename from library/compiler-builtins/crates/symbol-check/src/main.rs
rename to library/compiler-builtins/crates/symcheck/src/main.rs
index 11486b6ff1138..a88aeed40fb0d 100644
--- a/library/compiler-builtins/crates/symbol-check/src/main.rs
+++ b/library/compiler-builtins/crates/symcheck/src/main.rs
@@ -4,17 +4,22 @@
 //! Note that symcheck is a "hostprog", i.e. is built and run on the host target even when the
 //! actual target is cross compiled.
 
+#![allow(clippy::enum_variant_names)]
+
 use std::collections::{BTreeMap, BTreeSet, HashSet};
 use std::io::{BufRead, BufReader};
 use std::path::{Path, PathBuf};
 use std::process::{Command, Stdio, exit};
 use std::sync::LazyLock;
-use std::{env, fs};
+use std::{env, fmt, fs};
 
+use object::elf::{ProgramFlags, ProgramType};
 use object::read::archive::ArchiveFile;
+use object::read::pe::ImageOptionalHeader;
 use object::{
     Architecture, BinaryFormat, Endianness, File as ObjFile, FileFlags, Object, ObjectSection,
-    ObjectSymbol, Result as ObjResult, SectionFlags, Symbol, SymbolKind, SymbolScope, U32, elf,
+    ObjectSymbol, Result as ObjResult, SectionFlags, SubArchitecture, Symbol, SymbolKind,
+    SymbolScope, U32, elf, macho, pe, read,
 };
 use regex::Regex;
 use serde_json::Value;
@@ -25,8 +30,8 @@ const GNU_STACK: &str = ".note.GNU-stack";
 
 const USAGE: &str = "Usage:
 
-    symbol-check --build-and-check [--target TARGET] [--no-os] -- CARGO_BUILD_ARGS ...
-    symbol-check --check PATHS ...\
+    symcheck --build-and-check [--target TARGET] [--no-os] -- CARGO_BUILD_ARGS ...
+    symcheck --check [--target TARGET] PATHS ...\
 ";
 
 fn main() {
@@ -43,7 +48,10 @@ fn main() {
     opts.optopt(
         "",
         "target",
-        "Set the target for build-and-check. Falls back to the host target otherwise.",
+        // We could add a `--no-target-checks` flag to skip checks that need a target specified,
+        // if that winds up being useful at some point.
+        "Set the target when building, and the expected target for tests. Falls back to the host \
+        target if not specified.",
         "TARGET",
     );
     opts.optflag(
@@ -80,25 +88,32 @@ fn main() {
     for arg in &free_args {
         assert!(
             !arg.contains("--target"),
-            "target must be passed to symbol-check"
+            "target must be passed to symcheck"
         );
     }
 
+    let target = m.opt_str("target").unwrap_or(env!("HOST").to_string());
+    let target = Target::from_rustc(&target);
+
     if m.opt_present("build-and-check") {
-        let target = m.opt_str("target").unwrap_or(env!("HOST").to_string());
-        let paths = exec_cargo_with_args(&target, &free_args);
-        check_paths(&paths, no_os_target, check_visibility);
+        let paths = exec_cargo_with_args(&target.name, &free_args);
+        check_paths(&target, &paths, no_os_target, check_visibility);
     } else if m.opt_present("check") {
         if free_args.is_empty() {
             print_usage_and_exit(1);
         }
-        check_paths(&free_args, no_os_target, check_visibility);
+        check_paths(&target, &free_args, no_os_target, check_visibility);
     } else {
         print_usage_and_exit(1);
     }
 }
 
-fn check_paths<P: AsRef<Path>>(paths: &[P], no_os_target: bool, check_visibility: bool) {
+fn check_paths<P: AsRef<Path>>(
+    target: &Target,
+    paths: &[P],
+    no_os_target: bool,
+    check_visibility: bool,
+) {
     for path in paths {
         let path = path.as_ref();
         println!("Checking {}", path.display());
@@ -106,6 +121,7 @@ fn check_paths<P: AsRef<Path>>(paths: &[P], no_os_target: bool, check_visibility
 
         verify_no_duplicates(&archive);
         verify_core_symbols(&archive);
+        verify_expected_target(target, &archive);
         verify_no_exec_stack(&archive, no_os_target);
         if check_visibility {
             verify_hidden_visibility(&archive);
@@ -113,6 +129,231 @@ fn check_paths<P: AsRef<Path>>(paths: &[P], no_os_target: bool, check_visibility
     }
 }
 
+#[derive(Debug)]
+struct Target {
+    name: String,
+    arch: Architecture,
+    subarch: Option<SubArchitecture>,
+    endian: Endianness,
+    pointer_width: PointerWidth,
+    os: Os,
+    env: Option<String>,
+    abi: Option<String>,
+    families: Vec<String>,
+    vendors: Vec<String>,
+}
+
+impl Target {
+    /// Use `rustc` to query target information rather than parsing it ourselves.
+    fn from_rustc(target: &str) -> Self {
+        let mut cmd = Command::new("rustc");
+        cmd.args(["--target", target, "--print=cfg"])
+            .stdout(Stdio::piped());
+        println!("running: {cmd:?}");
+        let out = cmd.output().expect("failed to launch rustc");
+
+        let check_empty = |s: &str| {
+            if s.is_empty() {
+                None
+            } else {
+                Some(s.to_string())
+            }
+        };
+
+        let mut t = Target {
+            name: target.to_string(),
+            arch: Architecture::Unknown,
+            subarch: None,
+            endian: Endianness::Little,
+            pointer_width: PointerWidth::P64,
+            os: Os::Unknown,
+            env: None,
+            abi: None,
+            families: Vec::new(),
+            vendors: Vec::new(),
+        };
+
+        for line in out.stdout.lines() {
+            let line = line.expect("failed to read line");
+            let Some((k, v)) = line.split_once('=') else {
+                continue;
+            };
+            let v = v.trim_matches('"');
+
+            match k {
+                "target_os" => {
+                    t.os = match v {
+                        "aix" => Os::Aix,
+                        "amdhsa" => Os::Amdhsa,
+                        "android" => Os::Android,
+                        "cuda" => Os::Cuda,
+                        "cygwin" => Os::Cygwin,
+                        "dragonfly" => Os::Dragonfly,
+                        "emscripten" => Os::Emscripten,
+                        "espidf" => Os::EspIdf,
+                        "freebsd" => Os::FreeBsd,
+                        "fuchsia" => Os::Fuchsia,
+                        "haiku" => Os::Haiku,
+                        "helenos" => Os::HelenOs,
+                        "hermit" => Os::Hermit,
+                        "horizon" => Os::Horizon,
+                        "hurd" => Os::Hurd,
+                        "illumos" => Os::Illumos,
+                        "ios" => Os::IOs,
+                        "l4re" => Os::L4re,
+                        "linux" => Os::Linux,
+                        "lynxos178" => Os::LynxOs178,
+                        "macos" => Os::MacOs,
+                        "managarm" => Os::Managarm,
+                        "motor" => Os::Motor,
+                        "netbsd" => Os::NetBsd,
+                        "nto" => Os::Nto,
+                        "nuttx" => Os::Nuttx,
+                        "openbsd" => Os::OpenBsd,
+                        "psp" => Os::Psp,
+                        "psx" => Os::Psx,
+                        "qurt" => Os::Qurt,
+                        "redox" => Os::Redox,
+                        "rtems" => Os::Rtems,
+                        "solaris" => Os::Solaris,
+                        "solid_asp3" => Os::SolidAsp3,
+                        "teeos" => Os::Teeos,
+                        "trusty" => Os::Trusty,
+                        "tvos" => Os::TvOs,
+                        "uefi" => Os::Uefi,
+                        "vexos" => Os::Vexos,
+                        "visionos" => Os::VisionOs,
+                        "vita" => Os::Vita,
+                        "vxworks" => Os::VxXorks,
+                        "wasi" => Os::Wasi,
+                        "watchos" => Os::WatchOs,
+                        "windows" => Os::Windows,
+                        "xous" => Os::Xous,
+                        "zkvm" => Os::Zkvm,
+                        "unknown" | "none" => Os::Unknown,
+                        _ => panic!("unrecognized OS `{v}`"),
+                    }
+                }
+                "target_arch" => {
+                    t.arch = match v {
+                        "aarch64" => Architecture::Aarch64,
+                        "arm64ec" => {
+                            t.subarch = Some(SubArchitecture::Arm64EC);
+                            Architecture::Aarch64
+                        }
+                        "arm" => Architecture::Arm,
+                        "avr" => Architecture::Avr,
+                        "bpf" => Architecture::Bpf,
+                        "csky" => Architecture::Csky,
+                        "hexagon" => Architecture::Hexagon,
+                        "loongarch32" => Architecture::LoongArch32,
+                        "loongarch64" => Architecture::LoongArch64,
+                        "m68k" => Architecture::M68k,
+                        "mips" | "mips32r6" => Architecture::Mips,
+                        "mips64" | "mips64r6" => Architecture::Mips64,
+                        "msp430" => Architecture::Msp430,
+                        "powerpc" => Architecture::PowerPc,
+                        "powerpc64" => Architecture::PowerPc64,
+                        "riscv32" => Architecture::Riscv32,
+                        "riscv64" => Architecture::Riscv64,
+                        "s390x" => Architecture::S390x,
+                        "sparc" => Architecture::Sparc,
+                        "sparc64" => Architecture::Sparc64,
+                        "wasm32" => Architecture::Wasm32,
+                        "wasm64" => Architecture::Wasm64,
+                        "x86" => Architecture::I386,
+                        "x86_64" => Architecture::X86_64,
+                        "xtensa" => Architecture::Xtensa,
+                        _ => panic!("unrecognized arch {v}"),
+                    }
+                }
+                "target_abi" => t.abi = check_empty(v),
+                "target_env" => t.env = check_empty(v),
+                "target_family" if let Some(fam) = check_empty(v) => t.families.push(fam),
+                "target_vendor" if let Some(ven) = check_empty(v) => t.vendors.push(ven),
+                "target_endian" => {
+                    t.endian = match v {
+                        "little" => Endianness::Little,
+                        "big" => Endianness::Big,
+                        _ => panic!("unknown endian {v}"),
+                    }
+                }
+                "target_pointer_width" => {
+                    t.pointer_width = match v {
+                        "16" => PointerWidth::P16,
+                        "32" => PointerWidth::P32,
+                        "64" => PointerWidth::P64,
+                        _ => panic!("unknown pointer width {v}"),
+                    }
+                }
+                _ => (),
+            }
+        }
+
+        assert_ne!(t.arch, Architecture::Unknown, "arch not found");
+        t
+    }
+}
+
+#[derive(Clone, Copy, Debug, PartialEq, Eq)]
+enum Os {
+    Aix,
+    Amdhsa,
+    Android,
+    Cuda,
+    Cygwin,
+    Dragonfly,
+    Emscripten,
+    EspIdf,
+    FreeBsd,
+    Fuchsia,
+    Haiku,
+    HelenOs,
+    Hermit,
+    Horizon,
+    Hurd,
+    Illumos,
+    IOs,
+    L4re,
+    Linux,
+    LynxOs178,
+    MacOs,
+    Managarm,
+    Motor,
+    NetBsd,
+    Nto,
+    Nuttx,
+    OpenBsd,
+    Psp,
+    Psx,
+    Qurt,
+    Redox,
+    Rtems,
+    Solaris,
+    SolidAsp3,
+    Teeos,
+    Trusty,
+    TvOs,
+    Uefi,
+    Unknown,
+    Vexos,
+    VisionOs,
+    Vita,
+    VxXorks,
+    Wasi,
+    WatchOs,
+    Windows,
+    Xous,
+    Zkvm,
+}
+
+#[derive(Clone, Copy, Debug, PartialEq, Eq)]
+enum PointerWidth {
+    P16,
+    P32,
+    P64,
+}
+
 /// Run `cargo build` with the provided additional arguments, collecting the list of created
 /// libraries.
 fn exec_cargo_with_args(target: &str, args: &[&str]) -> Vec<PathBuf> {
@@ -366,6 +607,123 @@ fn verify_hidden_visibility(archive: &BinFile) {
     println!("    success: no visible symbols found");
 }
 
+/// Check that all object files are actually for the target architecture and, if provided,
+/// for the target operating system.
+fn verify_expected_target(target: &Target, archive: &BinFile) {
+    let mut mismatched = Vec::new();
+
+    archive.for_each_object(|obj, obj_path| {
+        let mut mismatch = |field: &str, a: &dyn fmt::Debug, b: &dyn fmt::Debug| {
+            let msg = format!("mismatched {field} {a:?} != {b:?}");
+            mismatched.push((obj_path.to_owned(), msg));
+        };
+
+        if obj.architecture() != target.arch {
+            mismatch("arch", &obj.architecture(), &target.arch);
+        }
+        if obj.sub_architecture() != target.subarch {
+            mismatch("subarch", &obj.sub_architecture(), &target.subarch);
+        }
+        if obj.endianness() != target.endian {
+            mismatch("endian", &obj.sub_architecture(), &target.endian);
+        }
+
+        let obj_os = match &obj {
+            ObjFile::Elf32(f) => elf_os(f),
+            ObjFile::Elf64(f) => elf_os(f),
+
+            ObjFile::MachO32(f) => mach_os(f),
+            ObjFile::MachO64(f) => mach_os(f),
+
+            // The non-executable header doesn't store OS
+            ObjFile::Coff(_) => Os::Windows,
+            ObjFile::CoffBig(_) => Os::Windows,
+            ObjFile::Pe32(f) => pe_os(f),
+            ObjFile::Pe64(f) => pe_os(f),
+
+            // Wasm files don't seem to have metadata (at least in `object`)
+            ObjFile::Wasm(_) => Os::Unknown,
+
+            // Out of supported platforms, this is only used by AIX
+            ObjFile::Xcoff32(_) => Os::Aix,
+            ObjFile::Xcoff64(_) => Os::Aix,
+
+            _ => {
+                unimplemented!(
+                    "os check for binary format {:?} is not yet supported",
+                    obj.format()
+                )
+            }
+        };
+
+        if !(obj_os == target.os
+            || obj_os == Os::Unknown
+            // Cygwin and Windows object files look the same
+            || (obj_os == Os::Windows && target.os == Os::Cygwin))
+        {
+            mismatch("OS", &obj_os, &target.os);
+        }
+    });
+
+    for (file, msg) in &mismatched {
+        eprintln!("in `{file}`: {msg}");
+    }
+
+    assert!(
+        mismatched.is_empty(),
+        "some object files do not match the intended target"
+    );
+    println!("    success: object files match target");
+}
+
+/* Note that we only match OS tags that have been tested. There are others for other platforms
+ * that Rust supports but aren't as easy to test, they can be added as needed. */
+
+/// Get the OS from an elf file, or `Unknown` if not specified.
+fn elf_os<Elf: read::elf::FileHeader>(f: &read::elf::ElfFile<Elf>) -> Os {
+    let os_abi = f.elf_header().e_ident().os_abi;
+    match os_abi {
+        elf::ELFOSABI_NONE => Os::Unknown,
+        elf::ELFOSABI_FREEBSD => Os::FreeBsd,
+        elf::ELFOSABI_SOLARIS => Os::Solaris,
+        // In practice, these seem not to be specified and instead match ELFOSABI_NONE.
+        elf::ELFOSABI_HURD => Os::Hurd,
+        elf::ELFOSABI_LINUX => Os::Linux,
+        elf::ELFOSABI_NETBSD => Os::NetBsd,
+        elf::ELFOSABI_OPENBSD => Os::OpenBsd,
+        _ => panic!("unrecognized ELF os_abi {os_abi}"),
+    }
+}
+
+/// Get the OS from a mach file, or `Unknown` if not specified.
+fn mach_os<Mach: read::macho::MachHeader>(f: &read::macho::MachOFile<Mach>) -> Os {
+    // Note that this only returns something on `.rmeta` objects, not `.o`s.
+    let Ok(Some((build_cmd, build_tool))) = f.build_version() else {
+        return Os::Unknown;
+    };
+    let platform = build_cmd.platform.get(f.endian());
+
+    match platform {
+        macho::PLATFORM_UNKNOWN => Os::Unknown,
+        macho::PLATFORM_MACOS => Os::MacOs,
+        macho::PLATFORM_IOS | macho::PLATFORM_IOSSIMULATOR | macho::PLATFORM_MACCATALYST => Os::IOs,
+        macho::PLATFORM_TVOS | macho::PLATFORM_TVOSSIMULATOR => Os::TvOs,
+        macho::PLATFORM_VISIONOS | macho::PLATFORM_VISIONOSSIMULATOR => Os::VisionOs,
+        macho::PLATFORM_WATCHOS | macho::PLATFORM_WATCHOSSIMULATOR => Os::WatchOs,
+        _ => panic!("unrecognized Mach-O platform {platform} ({build_cmd:?} {build_tool:?})"),
+    }
+}
+
+/// Get the OS from a PE file, or `Unknown` if not specified.
+fn pe_os<Pe: read::pe::ImageNtHeaders>(f: &read::pe::PeFile<Pe>) -> Os {
+    let opt_hdr = f.nt_headers().optional_header();
+    let sub = opt_hdr.subsystem();
+    match sub {
+        pe::IMAGE_SUBSYSTEM_WINDOWS_CUI | pe::IMAGE_SUBSYSTEM_WINDOWS_GUI => Os::Windows,
+        _ => panic!("unrecognized PE subsystem {sub}, {opt_hdr:?}"),
+    }
+}
+
 /// Reasons a binary is considered to have an executable stack.
 enum ExeStack {
     MissingGnuStackSec,
@@ -451,7 +809,8 @@ fn check_elf_exe_stack(obj: &ObjFile) -> Result<(), ExeStack> {
     // Check for PT_GNU_STACK marked executable
     let mut is_obj_exe = false;
     let mut found_gnu_stack = false;
-    let mut check_ph = |p_type: U32<Endianness>, p_flags: U32<Endianness>| {
+    let mut check_ph = |p_type: U32<Endianness, ProgramType>,
+                        p_flags: U32<Endianness, ProgramFlags>| {
         let ty = p_type.get(end);
         let flags = p_flags.get(end);
 
@@ -464,7 +823,7 @@ fn check_elf_exe_stack(obj: &ObjFile) -> Result<(), ExeStack> {
         if ty == elf::PT_GNU_STACK {
             assert!(!found_gnu_stack, "multiple PT_GNU_STACK sections");
             found_gnu_stack = true;
-            if flags & elf::PF_X != 0 {
+            if flags.contains(elf::PF_X) {
                 return Err(ExeStack::ExePtGnuStack);
             }
         }
@@ -495,11 +854,15 @@ fn check_elf_exe_stack(obj: &ObjFile) -> Result<(), ExeStack> {
     let mut gnu_stack_exe = None;
     let mut has_exe_sections = false;
     for sec in obj.sections() {
-        let SectionFlags::Elf { sh_flags } = sec.flags() else {
+        let SectionFlags::Elf {
+            sh_type: _,
+            sh_flags,
+        } = sec.flags()
+        else {
             unreachable!("only elf files are being checked");
         };
 
-        let is_sec_exe = sh_flags & u64::from(elf::SHF_EXECINSTR) != 0;
+        let is_sec_exe = sh_flags.contains(elf::SHF_EXECINSTR);
 
         // If the magic section is present, its exe bit tells us whether or not the object
         // file requires an executable stack.
@@ -534,7 +897,7 @@ fn check_elf_exe_stack(obj: &ObjFile) -> Result<(), ExeStack> {
     match obj.architecture() {
         // PPC64 doesn't set `.note.GNU-stack` since GNU nested functions don't need a trampoline,
         // <https://gcc.gnu.org/bugzilla/show_bug.cgi?id=21098>. This only applies to ELFv1.
-        Architecture::PowerPc64 if e_flags & elf::EF_PPC64_ABI != 2 => Ok(()),
+        Architecture::PowerPc64 if e_flags.0 & elf::EF_PPC64_ABI != 2 => Ok(()),
 
         _ => Err(ExeStack::MissingGnuStackSec),
     }
diff --git a/library/compiler-builtins/crates/symbol-check/tests/all.rs b/library/compiler-builtins/crates/symcheck/tests/all.rs
similarity index 85%
rename from library/compiler-builtins/crates/symbol-check/tests/all.rs
rename to library/compiler-builtins/crates/symcheck/tests/all.rs
index d038fd0dc935f..ce7d09798dc65 100644
--- a/library/compiler-builtins/crates/symbol-check/tests/all.rs
+++ b/library/compiler-builtins/crates/symcheck/tests/all.rs
@@ -1,7 +1,7 @@
-use std::env;
 use std::ffi::OsString;
 use std::path::{Path, PathBuf};
 use std::process::{Command, Stdio};
+use std::{env, str};
 
 use assert_cmd::assert::Assert;
 use assert_cmd::cargo::cargo_bin_cmd;
@@ -89,6 +89,43 @@ fn test_visible_symbols() {
     assert.failure().stderr_contains("found 1 visible symbols"); // good is visible.
 }
 
+#[test]
+fn test_target_mismatch() {
+    // Build with the target we know we have a toolchain for, but check against something else.
+    let t_build = TestTarget::from_env();
+    let t_check = if t_build.triple.starts_with("x86_64") {
+        TestTarget {
+            triple: "aarch64-unknown-linux-gnu".to_string(),
+        }
+    } else {
+        TestTarget {
+            triple: "x86_64-unknown-linux-gnu".to_string(),
+        }
+    };
+
+    let dir = tempdir().unwrap();
+    let lib_out = dir.path().join("libfoo.rlib");
+    t_build.rustc_build(&input_dir().join("good_lib.rs"), &lib_out, |cmd| cmd);
+
+    let assert = t_check.symcheck_exe().arg(&lib_out).assert();
+    assert
+        .failure()
+        .stderr_contains("some object files do not match the intended target");
+
+    // Try with C as well since some checks rely on rmeta archive members (Mach-O `build_version`).
+    let objs = t_build
+        .cc_build()
+        .file(input_dir().join("good_lib.c"))
+        .out_dir(&dir)
+        .compile_intermediates();
+    let [c_obj] = objs.as_slice() else { panic!() };
+
+    let assert = t_check.symcheck_exe().arg(c_obj).assert();
+    assert
+        .failure()
+        .stderr_contains("some object files do not match the intended target");
+}
+
 mod exe_stack {
     use super::*;
 
@@ -111,10 +148,7 @@ mod exe_stack {
 
         let assert = t.symcheck_exe().arg(obj).arg("--no-visibility").assert();
 
-        if (t.is_ppc64be() && t.is_glibc())
-            || t.no_os()
-            || t.binary_obj_format() != BinaryFormat::Elf
-        {
+        if t.is_ppc64_elfv1() || t.no_os() || t.binary_obj_format() != BinaryFormat::Elf {
             // Ppc64be ELFv1 doesn't emit `.note.GNU-stack`, not relevant without an OS, and non-elf
             // targets don't use `.note.GNU-stack`.
             assert.success();
@@ -146,7 +180,7 @@ mod exe_stack {
 
         let assert = t.symcheck_exe().arg(obj).arg("--no-visibility").assert();
 
-        if (t.is_ppc64be() && t.is_glibc()) || t.no_os() {
+        if t.is_ppc64_elfv1() || t.no_os() {
             // Ppc64be ELFv1 doesn't emit `.note.GNU-stack`, not relevant without an OS.
             assert.success();
             return;
@@ -270,7 +304,7 @@ impl TestTarget {
 
     fn symcheck_exe(&self) -> assert_cmd::Command {
         let mut cmd = cargo_bin_cmd!();
-        cmd.arg("--check");
+        cmd.arg("--check").arg("--target").arg(&self.triple);
         if self.no_os() {
             cmd.arg("--no-os");
         }
@@ -315,12 +349,16 @@ impl TestTarget {
         self.triple.contains("-windows-msvc")
     }
 
-    fn is_ppc64be(&self) -> bool {
-        self.triple.starts_with("powerpc64-")
-    }
-
-    fn is_glibc(&self) -> bool {
-        self.triple.contains("-linux-gnu")
+    fn is_ppc64_elfv1(&self) -> bool {
+        let output = Command::new("rustc")
+            .arg("--target")
+            .arg(&self.triple)
+            .arg("--print=cfg")
+            .output()
+            .unwrap();
+        assert!(output.status.success());
+        let stdout = str::from_utf8(&output.stdout).unwrap();
+        self.triple.starts_with("powerpc64") && stdout.contains(r#"target_abi="elfv1""#)
     }
 
     /// True if the target needs `--no-os` passed to symcheck.
diff --git a/library/compiler-builtins/crates/symbol-check/tests/input/core_symbols.rs b/library/compiler-builtins/crates/symcheck/tests/input/core_symbols.rs
similarity index 100%
rename from library/compiler-builtins/crates/symbol-check/tests/input/core_symbols.rs
rename to library/compiler-builtins/crates/symcheck/tests/input/core_symbols.rs
diff --git a/library/compiler-builtins/crates/symbol-check/tests/input/duplicates.rs b/library/compiler-builtins/crates/symcheck/tests/input/duplicates.rs
similarity index 100%
rename from library/compiler-builtins/crates/symbol-check/tests/input/duplicates.rs
rename to library/compiler-builtins/crates/symcheck/tests/input/duplicates.rs
diff --git a/library/compiler-builtins/crates/symbol-check/tests/input/good_bin.c b/library/compiler-builtins/crates/symcheck/tests/input/good_bin.c
similarity index 100%
rename from library/compiler-builtins/crates/symbol-check/tests/input/good_bin.c
rename to library/compiler-builtins/crates/symcheck/tests/input/good_bin.c
diff --git a/library/compiler-builtins/crates/symcheck/tests/input/good_lib.c b/library/compiler-builtins/crates/symcheck/tests/input/good_lib.c
new file mode 100644
index 0000000000000..0b7e431cb90f2
--- /dev/null
+++ b/library/compiler-builtins/crates/symcheck/tests/input/good_lib.c
@@ -0,0 +1 @@
+void good() {}
diff --git a/library/compiler-builtins/crates/symbol-check/tests/input/good_lib.rs b/library/compiler-builtins/crates/symcheck/tests/input/good_lib.rs
similarity index 100%
rename from library/compiler-builtins/crates/symbol-check/tests/input/good_lib.rs
rename to library/compiler-builtins/crates/symcheck/tests/input/good_lib.rs
diff --git a/library/compiler-builtins/crates/symbol-check/tests/input/has_exe_gnu_stack_section.c b/library/compiler-builtins/crates/symcheck/tests/input/has_exe_gnu_stack_section.c
similarity index 100%
rename from library/compiler-builtins/crates/symbol-check/tests/input/has_exe_gnu_stack_section.c
rename to library/compiler-builtins/crates/symcheck/tests/input/has_exe_gnu_stack_section.c
diff --git a/library/compiler-builtins/crates/symbol-check/tests/input/missing_gnu_stack_section.S b/library/compiler-builtins/crates/symcheck/tests/input/missing_gnu_stack_section.S
similarity index 100%
rename from library/compiler-builtins/crates/symbol-check/tests/input/missing_gnu_stack_section.S
rename to library/compiler-builtins/crates/symcheck/tests/input/missing_gnu_stack_section.S
diff --git a/library/compiler-builtins/crates/util/Cargo.toml b/library/compiler-builtins/crates/util/Cargo.toml
index b0a365e4735b0..c56e2cc12ea58 100644
--- a/library/compiler-builtins/crates/util/Cargo.toml
+++ b/library/compiler-builtins/crates/util/Cargo.toml
@@ -6,7 +6,6 @@ publish = false
 license = "MIT OR Apache-2.0"
 
 [dependencies]
-cfg-if.workspace = true
 libm.workspace = true
 libm-macros.workspace = true
 libm-test.workspace = true
diff --git a/library/compiler-builtins/crates/util/src/main.rs b/library/compiler-builtins/crates/util/src/main.rs
index ac2c126d8c0d1..aa79354a57159 100644
--- a/library/compiler-builtins/crates/util/src/main.rs
+++ b/library/compiler-builtins/crates/util/src/main.rs
@@ -8,7 +8,6 @@ use std::env;
 use std::num::ParseIntError;
 use std::str::FromStr;
 
-use cfg_if::cfg_if;
 use libm::support::{Float, Hex, hf32, hf64};
 #[cfg(feature = "build-mpfr")]
 use libm_test::mpfloat::MpOp;
@@ -127,13 +126,14 @@ fn do_eval(basis: &str, op: &str, inputs: &[&str]) {
 fn do_classify(inputs: &[&str]) {
     for s in inputs {
         if let Some(s) = s.strip_suffix("f16") {
-            cfg_if! {
-                if #[cfg(f16_enabled)] {
+            cfg_select! {
+                f16_enabled => {
                     let s = s.trim_end_matches("_");
                     let x: f16 = parse(&[s], 0);
                     classify_print(x);
                     continue;
-                } else {
+                }
+                _ => {
                     panic!("parsing this type requires f16 support: `{s}`");
                 }
             }
@@ -150,15 +150,18 @@ fn do_classify(inputs: &[&str]) {
             continue;
         }
         if let Some(s) = s.strip_suffix("f128") {
-            cfg_if! {
-                if #[cfg(all(f128_enabled, feature = "build-mpfr"))] {
+            cfg_select! {
+                all(f128_enabled, feature = "build-mpfr") => {
                     let s = s.trim_end_matches("_");
                     let x: f128 = parse_rug(&[s], 0);
                     classify_print(x);
                     continue;
-                } else {
-                    panic!("parsing this type requires f128 support and \
-                            the `build-mpfr` feature: `{s}`");
+                }
+                _ => {
+                    panic!(
+                        "parsing this type requires f128 support and \
+                        the `build-mpfr` feature: `{s}`"
+                    );
                 }
             }
         };
diff --git a/library/compiler-builtins/etc/function-definitions.json b/library/compiler-builtins/etc/function-definitions.json
index f59bb7ceebb42..88070abf0ce09 100644
--- a/library/compiler-builtins/etc/function-definitions.json
+++ b/library/compiler-builtins/etc/function-definitions.json
@@ -343,6 +343,7 @@
     "fma": {
         "sources": [
             "libm/src/math/arch/aarch64/fma.rs",
+            "libm/src/math/arch/loongarch/fma.rs",
             "libm/src/math/arch/x86/fma.rs",
             "libm/src/math/fma.rs",
             "libm/src/math/generic/fma.rs"
@@ -352,6 +353,7 @@
     "fmaf": {
         "sources": [
             "libm/src/math/arch/aarch64/fma.rs",
+            "libm/src/math/arch/loongarch/fma.rs",
             "libm/src/math/arch/x86/fma.rs",
             "libm/src/math/fma.rs",
             "libm/src/math/generic/fma.rs"
@@ -832,6 +834,7 @@
         "sources": [
             "libm/src/math/arch/aarch64/rounding.rs",
             "libm/src/math/arch/i586/rounding.rs",
+            "libm/src/math/arch/loongarch/rounding.rs",
             "libm/src/math/arch/wasm32/rounding.rs",
             "libm/src/math/generic/rint.rs",
             "libm/src/math/rint.rs"
@@ -841,6 +844,7 @@
     "rintf": {
         "sources": [
             "libm/src/math/arch/aarch64/rounding.rs",
+            "libm/src/math/arch/loongarch/rounding.rs",
             "libm/src/math/arch/wasm32/rounding.rs",
             "libm/src/math/generic/rint.rs",
             "libm/src/math/rint.rs"
@@ -981,6 +985,7 @@
     "sqrt": {
         "sources": [
             "libm/src/math/arch/aarch64/sqrt.rs",
+            "libm/src/math/arch/loongarch/sqrt.rs",
             "libm/src/math/arch/wasm32/sqrt.rs",
             "libm/src/math/arch/x86/sqrt.rs",
             "libm/src/math/generic/sqrt.rs",
@@ -991,6 +996,7 @@
     "sqrtf": {
         "sources": [
             "libm/src/math/arch/aarch64/sqrt.rs",
+            "libm/src/math/arch/loongarch/sqrt.rs",
             "libm/src/math/arch/wasm32/sqrt.rs",
             "libm/src/math/arch/x86/sqrt.rs",
             "libm/src/math/generic/sqrt.rs",
diff --git a/library/compiler-builtins/libm-test/src/generate.rs b/library/compiler-builtins/libm-test/src/generate.rs
index 7118752f4f0bb..29c2b9f92236b 100644
--- a/library/compiler-builtins/libm-test/src/generate.rs
+++ b/library/compiler-builtins/libm-test/src/generate.rs
@@ -1,5 +1,6 @@
 //! Different generators that can create random or systematic bit patterns.
 
+pub mod bitpattern;
 pub mod case_list;
 pub mod edge_cases;
 pub mod random;
diff --git a/library/compiler-builtins/libm-test/src/generate/bitpattern.rs b/library/compiler-builtins/libm-test/src/generate/bitpattern.rs
new file mode 100644
index 0000000000000..45b2ff0b21acb
--- /dev/null
+++ b/library/compiler-builtins/libm-test/src/generate/bitpattern.rs
@@ -0,0 +1,371 @@
+use libm::support::{Float, Int, MinInt};
+
+/// Iterate all the bitwise subsets of the given mask.
+///
+/// Produces the same sequence as `(0..=uN::MAX).filter(|x| x & !mask == 0)`,
+/// but each item is generated in O(1) time.
+///
+/// # Panics
+///
+/// Panics if the mask has all bits set.
+///
+/// # Example
+///
+/// ```ignore
+/// assert!(bitwise_subsets(0b1001).eq([0b0000, 0b0001, 0b1000, 0b1001]));
+/// ```
+fn bitwise_subsets<I>(mask: I) -> impl Iterator<Item = I> + Clone
+where
+    I: Int<Unsigned = I>,
+{
+    assert!(
+        mask != I::MAX,
+        "to optimize the implementation, varying every bit is not supported"
+    );
+    let fixed = !mask;
+    let mut counter = fixed - I::ONE;
+
+    // `(counter + 1) & !fixed` is initially 0, and increases after each item returned
+    std::iter::from_fn(move || {
+        counter = counter.checked_add(I::ONE)? | fixed;
+        Some(counter ^ fixed)
+    })
+}
+
+/// Create a bitmask with `count` ones. The ones are filled in this order:
+///
+/// 1. Sign bit
+/// 2. Significand low bits
+/// 3. Significand high bits, exponent low bits, exponent high bits (increment together)
+fn most_wanted_bitmask<F: Float>(count: u32) -> F::Int {
+    if count == 0 {
+        return F::Int::ZERO;
+    }
+    let mut mask = F::SIGN_MASK;
+    let n = (count - 1) / 4;
+    mask |= low_mask_bits(n, F::EXP_MASK);
+    mask |= high_mask_bits(n, F::EXP_MASK);
+    mask |= high_mask_bits(n, F::SIG_MASK);
+    // spend most of the remaining budget on the least significant bits, then use up remainders
+    mask |= low_mask_bits(count - mask.count_ones(), F::SIG_MASK);
+    mask |= high_mask_bits(n + count - mask.count_ones(), F::SIG_MASK);
+    mask |= high_mask_bits(n + count - mask.count_ones(), F::EXP_MASK);
+    mask |= low_mask_bits(n + count - mask.count_ones(), F::EXP_MASK);
+    mask
+}
+
+/// Similar to `most_wanted_bitmask` but adds bits around the middle of the int rather than at
+/// a sign/exponent/significand boundary.
+fn most_wanted_int_bitmask<I: Int<Unsigned = I>>(count: u32) -> I {
+    if count == 0 {
+        return I::ZERO;
+    }
+    let mut mask = I::ZERO;
+    let n = count / 4;
+
+    let low_mask = I::MAX >> (I::BITS / 2);
+    let high_mask = low_mask << (I::BITS / 2);
+
+    mask |= low_mask_bits(n, high_mask);
+    mask |= high_mask_bits(n, high_mask);
+    mask |= high_mask_bits(n, low_mask);
+    // spend most of the remaining budget on the least significant bits, then use up remainders
+    mask |= low_mask_bits(count - mask.count_ones(), low_mask);
+    mask |= high_mask_bits(n + count - mask.count_ones(), low_mask);
+    mask |= high_mask_bits(n + count - mask.count_ones(), high_mask);
+    mask |= low_mask_bits(n + count - mask.count_ones(), high_mask);
+    mask
+}
+
+/// Set `count` bits in the LSB of `mask`.
+fn low_mask_bits<I: Int>(count: u32, mask: I) -> I {
+    mask & (mask >> (mask.count_ones().saturating_sub(count)))
+}
+
+/// Set `count` bits in the MSB of `mask`.
+fn high_mask_bits<I: Int>(count: u32, mask: I) -> I {
+    mask & (mask << (mask.count_ones().saturating_sub(count)))
+}
+
+/// Biased generator for floats.
+///
+/// Starts with the first value of `fillers`, then toggles `bits_to_vary` bits exhaustively. Once
+/// that has completed, move on to the next filler.
+///
+/// The returned iterator will produce `fillers.len() << bits_to_vary` items.
+#[cfg_attr(not(test), expect(dead_code))]
+fn float_gen<F>(
+    bits_to_vary: u32,
+    fillers: impl IntoIterator<Item = F::Int>,
+) -> impl Iterator<Item = F>
+where
+    F: Float,
+    F::Int: Int<Unsigned = F::Int>,
+{
+    let varying = most_wanted_bitmask::<F>(bits_to_vary);
+    let patterns = bitwise_subsets(varying);
+
+    fillers
+        .into_iter()
+        .flat_map(move |preset| patterns.clone().map(move |x| x ^ preset))
+        .map(F::from_bits)
+}
+
+/// See [`float_gen`] docs for details.
+#[cfg_attr(not(test), expect(dead_code))]
+fn int_gen<I>(bits_to_vary: u32, fillers: impl IntoIterator<Item = I>) -> impl Iterator<Item = I>
+where
+    I: Int<Unsigned = I>,
+{
+    let varying = most_wanted_int_bitmask::<I>(bits_to_vary);
+    let patterns = bitwise_subsets(varying);
+
+    fillers
+        .into_iter()
+        .flat_map(move |preset| patterns.clone().map(move |x| x ^ preset))
+}
+
+#[cfg(test)]
+mod test {
+    use super::*;
+    use crate::f8;
+
+    #[test]
+    fn equivalence() {
+        // with a small integer type, we can easily verify that behaviour matches for all arguments
+        for mask in 0..u8::MAX {
+            let expect = (0..=u8::MAX).filter(|x| x & !mask == 0);
+            assert!(bitwise_subsets(mask).eq(expect));
+        }
+    }
+
+    #[test]
+    fn most_wanted() {
+        let expected8 = [
+            0b0_0000_000,
+            //
+            0b1_0000_000,
+            0b1_0000_001,
+            0b1_0000_011,
+            0b1_0000_111,
+            //
+            0b1_1001_101,
+            0b1_1001_111,
+            0b1_1101_111,
+            0b1_1111_111,
+        ];
+        let expected32 = [
+            0b0_00000000_00000000000000000000000,
+            //
+            0b1_00000000_00000000000000000000000,
+            0b1_00000000_00000000000000000000001,
+            0b1_00000000_00000000000000000000011,
+            0b1_00000000_00000000000000000000111,
+            //
+            0b1_10000001_10000000000000000000001,
+            0b1_10000001_10000000000000000000011,
+            0b1_10000001_10000000000000000000111,
+            0b1_10000001_10000000000000000001111,
+            //
+            0b1_11000011_11000000000000000000011,
+            0b1_11000011_11000000000000000000111,
+            0b1_11000011_11000000000000000001111,
+            0b1_11000011_11000000000000000011111,
+            //
+            0b1_11100111_11100000000000000000111,
+            0b1_11100111_11100000000000000001111,
+            0b1_11100111_11100000000000000011111,
+            0b1_11100111_11100000000000000111111,
+            //
+            0b1_11111111_11110000000000000001111,
+            0b1_11111111_11110000000000000011111,
+            0b1_11111111_11110000000000000111111,
+            0b1_11111111_11110000000000001111111,
+            //
+            0b1_11111111_11111000000000001111111,
+            0b1_11111111_11111000000000011111111,
+            0b1_11111111_11111000000000111111111,
+            0b1_11111111_11111000000001111111111,
+            //
+            0b1_11111111_11111100000001111111111,
+            0b1_11111111_11111100000011111111111,
+            0b1_11111111_11111100000111111111111,
+            0b1_11111111_11111100001111111111111,
+            //
+            0b1_11111111_11111110001111111111111,
+            0b1_11111111_11111110011111111111111,
+            0b1_11111111_11111110111111111111111,
+            0b1_11111111_11111111111111111111111,
+        ];
+        for k in 0..=8 {
+            let mask = most_wanted_bitmask::<f8>(k);
+            assert_eq!(mask, expected8[k as usize], "{k}");
+            assert_eq!(mask.count_ones(), k);
+        }
+        for k in 0..=32 {
+            let mask = most_wanted_bitmask::<f32>(k);
+            assert_eq!(mask, expected32[k as usize], "{k}");
+            assert_eq!(mask.count_ones(), k);
+        }
+    }
+
+    #[test]
+    fn most_wanted_int() {
+        let expected = [
+            0b0000_0000_0000_0000,
+            0b0000_0000_0000_0001,
+            0b0000_0000_0000_0011,
+            0b0000_0000_0000_0111,
+            //
+            0b1000_0001_1000_0001,
+            0b1000_0001_1000_0011,
+            0b1000_0001_1000_0111,
+            0b1000_0001_1000_1111,
+            //
+            0b1100_0011_1100_0011,
+            0b1100_0011_1100_0111,
+            0b1100_0011_1100_1111,
+            0b1100_0011_1101_1111,
+            //
+            0b1110_0111_1110_0111,
+            0b1110_0111_1110_1111,
+            0b1110_0111_1111_1111,
+            0b1111_0111_1111_1111,
+            //
+            0b1111_1111_1111_1111,
+        ];
+        let mut x = vec![];
+        for k in 0..=16 {
+            let mask = most_wanted_int_bitmask::<u16>(k);
+            x.push(mask);
+            assert_eq!(mask, expected[k as usize], "{k}");
+            assert_eq!(mask.count_ones(), k);
+        }
+    }
+
+    #[test]
+    #[cfg(f16_enabled)]
+    fn gen_with_fillers() {
+        let expected = [
+            // Filler: zeros
+            0b0_00000_0000000000,
+            0b0_00000_0000000001,
+            0b0_00000_0000000010,
+            0b0_00000_0000000011,
+            0b1_00000_0000000000,
+            0b1_00000_0000000001,
+            0b1_00000_0000000010,
+            0b1_00000_0000000011,
+            // Filler: ones
+            0b1_11111_1111111111,
+            0b1_11111_1111111110,
+            0b1_11111_1111111101,
+            0b1_11111_1111111100,
+            0b0_11111_1111111111,
+            0b0_11111_1111111110,
+            0b0_11111_1111111101,
+            0b0_11111_1111111100,
+            // Filler: pattern
+            0b1_00110_1000101011,
+            0b1_00110_1000101010,
+            0b1_00110_1000101001,
+            0b1_00110_1000101000,
+            0b0_00110_1000101011,
+            0b0_00110_1000101010,
+            0b0_00110_1000101001,
+            0b0_00110_1000101000,
+        ];
+        let v = float_gen::<f16>(3, [0, u16::MAX, 0b1_00110_1000101011])
+            .map(|x| x.to_bits())
+            .collect::<Vec<_>>();
+        assert_eq!(expected.as_slice(), v);
+    }
+
+    #[test]
+    fn gen_int_with_fillers() {
+        let expected = [
+            // Filler: zeros
+            0b0000_0000_0000_0000,
+            0b0000_0000_0000_0001,
+            0b0000_0000_0000_0010,
+            0b0000_0000_0000_0011,
+            0b0000_0000_0000_0100,
+            0b0000_0000_0000_0101,
+            0b0000_0000_0000_0110,
+            0b0000_0000_0000_0111,
+            // Filler: ones
+            0b1111_1111_1111_1111,
+            0b1111_1111_1111_1110,
+            0b1111_1111_1111_1101,
+            0b1111_1111_1111_1100,
+            0b1111_1111_1111_1011,
+            0b1111_1111_1111_1010,
+            0b1111_1111_1111_1001,
+            0b1111_1111_1111_1000,
+            // Filler: pattern
+            0b1001_1010_0010_1011,
+            0b1001_1010_0010_1010,
+            0b1001_1010_0010_1001,
+            0b1001_1010_0010_1000,
+            0b1001_1010_0010_1111,
+            0b1001_1010_0010_1110,
+            0b1001_1010_0010_1101,
+            0b1001_1010_0010_1100,
+        ];
+        let v = int_gen::<u16>(3, [0, u16::MAX, 0b1001_1010_0010_1011]).collect::<Vec<_>>();
+        assert_eq!(expected.as_slice(), v);
+    }
+
+    #[test]
+    fn gen_includes_specials() {
+        let v: Vec<_> = float_gen(5, vec![0, 0x7fffff, !0x7fffff, !0])
+            .map(f32::to_bits)
+            .collect();
+        for x in &[
+            0.0,
+            f32::from_bits(1),
+            f32::MIN_POSITIVE,
+            f32::MAX,
+            f32::INFINITY,
+            f32::NAN,
+        ] {
+            assert!(v.contains(&x.to_bits()), "{x} not found");
+            assert!(v.contains(&(-x).to_bits()), "-{x} not found");
+        }
+    }
+
+    #[test]
+    fn count() {
+        for k in 0..10 {
+            assert!(float_gen::<f32>(k, vec![0]).count() == 1 << k);
+            assert!(float_gen::<f32>(k, vec![0, !0]).count() == 2 << k);
+            assert!(float_gen::<f32>(k, vec![0, 1, 2]).count() == 3 << k);
+        }
+    }
+
+    #[test]
+    fn specific() {
+        let iter = float_gen::<f32>(1, vec![0]).map(f32::to_bits);
+        assert!(iter.eq([0.0_f32.to_bits(), (-0.0_f32).to_bits()]));
+        let iter = float_gen::<f64>(1, vec![0]).map(f64::to_bits);
+        assert!(iter.eq([0.0_f64.to_bits(), (-0.0_f64).to_bits()]));
+
+        let mut v: Vec<_> = float_gen::<f32>(5, vec![0]).map(f32::to_bits).collect();
+        assert!(v.len() == 32);
+        assert!(v.is_sorted());
+        v.dedup();
+        assert!(v.len() == 32);
+        for bits in v {
+            assert!(bits & 0xc0c0_0001 == bits);
+        }
+
+        let mut v: Vec<_> = float_gen::<f64>(5, vec![0]).map(f64::to_bits).collect();
+        assert!(v.len() == 32);
+        assert!(v.is_sorted());
+        v.dedup();
+        assert!(v.len() == 32);
+        for bits in v {
+            assert!(bits & 0xc018_0000_0000_0001 == bits);
+        }
+    }
+}
diff --git a/library/compiler-builtins/libm-test/src/generate/random.rs b/library/compiler-builtins/libm-test/src/generate/random.rs
index 32bd2f24ee044..b6cd315ef34c1 100644
--- a/library/compiler-builtins/libm-test/src/generate/random.rs
+++ b/library/compiler-builtins/libm-test/src/generate/random.rs
@@ -12,7 +12,7 @@ use rand_chacha::ChaCha8Rng;
 use crate::CheckCtx;
 use crate::generate::{KnownSize, product2, product3};
 use crate::num::full_range;
-use crate::run_cfg::{int_range, iteration_count};
+use crate::run_cfg::{arg_max_iterations, int_range};
 
 pub(crate) const SEED_ENV: &str = "LIBM_SEED";
 
@@ -57,7 +57,7 @@ macro_rules! impl_random_input {
     ($fty:ty) => {
         impl RandomInput for ($fty,) {
             fn get_cases(ctx: &CheckCtx) -> (impl Iterator<Item = Self>, u64) {
-                let count = iteration_count(ctx, 0);
+                let count = arg_max_iterations(ctx, 0);
                 let iter = random_floats(count).map(|f: $fty| (f,));
                 (iter, count)
             }
@@ -65,8 +65,8 @@ macro_rules! impl_random_input {
 
         impl RandomInput for ($fty, $fty) {
             fn get_cases(ctx: &CheckCtx) -> (impl Iterator<Item = Self>, u64) {
-                let count0 = iteration_count(ctx, 0);
-                let count1 = iteration_count(ctx, 1);
+                let count0 = arg_max_iterations(ctx, 0);
+                let count1 = arg_max_iterations(ctx, 1);
                 let iter0 = random_floats(count0);
                 let iter1 = random_floats(count1);
                 let iter = product2(iter0, iter1);
@@ -77,9 +77,9 @@ macro_rules! impl_random_input {
 
         impl RandomInput for ($fty, $fty, $fty) {
             fn get_cases(ctx: &CheckCtx) -> (impl Iterator<Item = Self>, u64) {
-                let count0 = iteration_count(ctx, 0);
-                let count1 = iteration_count(ctx, 1);
-                let count2 = iteration_count(ctx, 2);
+                let count0 = arg_max_iterations(ctx, 0);
+                let count1 = arg_max_iterations(ctx, 1);
+                let count2 = arg_max_iterations(ctx, 2);
                 let iter0 = random_floats(count0);
                 let iter1 = random_floats(count1);
                 let iter2 = random_floats(count2);
@@ -91,8 +91,8 @@ macro_rules! impl_random_input {
 
         impl RandomInput for (i32, $fty) {
             fn get_cases(ctx: &CheckCtx) -> (impl Iterator<Item = Self>, u64) {
-                let count0 = iteration_count(ctx, 0);
-                let count1 = iteration_count(ctx, 1);
+                let count0 = arg_max_iterations(ctx, 0);
+                let count1 = arg_max_iterations(ctx, 1);
                 let range0 = int_range::<i32>(ctx, 0).unwrap_or(full_range());
                 let iter0 = random_ints(count0, range0);
                 let iter1 = random_floats(count1);
@@ -104,8 +104,8 @@ macro_rules! impl_random_input {
 
         impl RandomInput for ($fty, i32) {
             fn get_cases(ctx: &CheckCtx) -> (impl Iterator<Item = Self>, u64) {
-                let count0 = iteration_count(ctx, 0);
-                let count1 = iteration_count(ctx, 1);
+                let count0 = arg_max_iterations(ctx, 0);
+                let count1 = arg_max_iterations(ctx, 1);
                 let range1 = int_range::<i32>(ctx, 1).unwrap_or(full_range());
                 let iter0 = random_floats(count0);
                 let iter1 = random_ints(count1, range1.clone());
@@ -128,7 +128,7 @@ macro_rules! impl_random_input_int {
     (@skip_u32 $ity:ty) => {
         impl RandomInput for ($ity,) {
             fn get_cases(ctx: &CheckCtx) -> (impl Iterator<Item = Self>, u64) {
-                let count = iteration_count(ctx, 0);
+                let count = arg_max_iterations(ctx, 0);
                 let range = int_range::<$ity>(ctx, 0).unwrap_or(full_range());
                 let iter = random_ints(count, range).map(|f: $ity| (f,));
                 (iter, count)
@@ -137,8 +137,8 @@ macro_rules! impl_random_input_int {
 
         impl RandomInput for ($ity, $ity) {
             fn get_cases(ctx: &CheckCtx) -> (impl Iterator<Item = Self>, u64) {
-                let count0 = iteration_count(ctx, 0);
-                let count1 = iteration_count(ctx, 1);
+                let count0 = arg_max_iterations(ctx, 0);
+                let count1 = arg_max_iterations(ctx, 1);
                 let range0 = int_range::<$ity>(ctx, 0).unwrap_or(full_range());
                 let range1 = int_range::<$ity>(ctx, 1).unwrap_or(full_range());
                 let iter0 = random_ints(count0, range0);
@@ -153,8 +153,8 @@ macro_rules! impl_random_input_int {
 
         impl RandomInput for ($ity, u32) {
             fn get_cases(ctx: &CheckCtx) -> (impl Iterator<Item = Self>, u64) {
-                let count0 = iteration_count(ctx, 0);
-                let count1 = iteration_count(ctx, 1);
+                let count0 = arg_max_iterations(ctx, 0);
+                let count1 = arg_max_iterations(ctx, 1);
                 let range0 = int_range::<$ity>(ctx, 0).unwrap_or(full_range());
                 let range1 = int_range::<u32>(ctx, 1).unwrap_or(full_range());
                 let iter0 = random_ints(count0, range0);
diff --git a/library/compiler-builtins/libm-test/src/generate/spaced.rs b/library/compiler-builtins/libm-test/src/generate/spaced.rs
index 192106cc61827..051dd2687d8cb 100644
--- a/library/compiler-builtins/libm-test/src/generate/spaced.rs
+++ b/library/compiler-builtins/libm-test/src/generate/spaced.rs
@@ -6,7 +6,7 @@ use libm::support::{Float, Int, MinInt};
 use crate::domain::get_domain;
 use crate::generate::{product2, product3};
 use crate::num::full_range;
-use crate::run_cfg::{int_range, iteration_count};
+use crate::run_cfg::{arg_max_iterations, int_range};
 use crate::{Arg0, Arg1, Arg2, CheckCtx, MathOp, linear_ints, logspace};
 
 /// Generate a sequence of inputs that eiher cover the domain in completeness (for smaller float
@@ -101,7 +101,7 @@ macro_rules! impl_spaced_input {
             Op: MathOp<RustArgs = Self>,
         {
             fn get_cases(ctx: &CheckCtx) -> (impl Iterator<Item = Self>, u64) {
-                let max_steps0 = iteration_count(ctx, 0);
+                let max_steps0 = arg_max_iterations(ctx, 0);
 
                 // Unary tests: `f16` and `f32` may be exhaustive.
                 if let Some(exhaustive_steps0) = total_value_count::<Arg0<Op>>()
@@ -125,8 +125,8 @@ macro_rules! impl_spaced_input {
             Op: MathOp<RustArgs = Self>,
         {
             fn get_cases(ctx: &CheckCtx) -> (impl Iterator<Item = Self>, u64) {
-                let max_steps0 = iteration_count(ctx, 0);
-                let max_steps1 = iteration_count(ctx, 1);
+                let max_steps0 = arg_max_iterations(ctx, 0);
+                let max_steps1 = arg_max_iterations(ctx, 1);
 
                 // Binary test: `f16` may be exhaustive.
                 if let Some(exhaustive_steps0) = total_value_count::<Arg0<Op>>()
@@ -159,9 +159,9 @@ macro_rules! impl_spaced_input {
             Op: MathOp<RustArgs = Self>,
         {
             fn get_cases(ctx: &CheckCtx) -> (impl Iterator<Item = Self>, u64) {
-                let max_steps0 = iteration_count(ctx, 0);
-                let max_steps1 = iteration_count(ctx, 1);
-                let max_steps2 = iteration_count(ctx, 2);
+                let max_steps0 = arg_max_iterations(ctx, 0);
+                let max_steps1 = arg_max_iterations(ctx, 1);
+                let max_steps2 = arg_max_iterations(ctx, 2);
 
                 // Ternary test: `f16` may be exhaustive tested if `LIBM_EXTENSIVE_TESTS`
                 // is incresed.
@@ -200,8 +200,8 @@ macro_rules! impl_spaced_input {
         {
             fn get_cases(ctx: &CheckCtx) -> (impl Iterator<Item = Self>, u64) {
                 let range0 = int_range(ctx, 0).unwrap_or(full_range());
-                let max_steps0 = iteration_count(ctx, 0);
-                let max_steps1 = iteration_count(ctx, 1);
+                let max_steps0 = arg_max_iterations(ctx, 0);
+                let max_steps1 = arg_max_iterations(ctx, 1);
 
                 if let Some(exhaustive_steps0) = total_value_count_int::<Arg0<Op>>()
                     && exhaustive_steps0 <= max_steps0
@@ -232,9 +232,9 @@ macro_rules! impl_spaced_input {
             Op: MathOp<RustArgs = Self>,
         {
             fn get_cases(ctx: &CheckCtx) -> (impl Iterator<Item = Self>, u64) {
-                let max_steps0 = iteration_count(ctx, 0);
+                let max_steps0 = arg_max_iterations(ctx, 0);
                 let range1 = int_range(ctx, 1).unwrap_or(full_range());
-                let max_steps1 = iteration_count(ctx, 1);
+                let max_steps1 = arg_max_iterations(ctx, 1);
 
                 if let Some(exhaustive_steps0) = total_value_count::<Arg0<Op>>()
                     && exhaustive_steps0 <= max_steps0
@@ -275,7 +275,7 @@ macro_rules! impl_spaced_input_int {
         {
             fn get_cases(ctx: &CheckCtx) -> (impl Iterator<Item = Self>, u64) {
                 let range = int_range(ctx, 0).unwrap_or(full_range());
-                let max_steps0 = iteration_count(ctx, 0);
+                let max_steps0 = arg_max_iterations(ctx, 0);
 
                 if let Some(steps0) = total_value_count_int::<Arg0<Op>>()
                     && steps0 <= max_steps0
@@ -297,8 +297,8 @@ macro_rules! impl_spaced_input_int {
             fn get_cases(ctx: &CheckCtx) -> (impl Iterator<Item = Self>, u64) {
                 let range0 = int_range(ctx, 0).unwrap_or(full_range());
                 let range1 = int_range(ctx, 1).unwrap_or(full_range());
-                let max_steps0 = iteration_count(ctx, 0);
-                let max_steps1 = iteration_count(ctx, 0);
+                let max_steps0 = arg_max_iterations(ctx, 0);
+                let max_steps1 = arg_max_iterations(ctx, 0);
 
                 if let Some(steps0) = total_value_count_int::<Arg0<Op>>()
                     && steps0 <= max_steps0
@@ -331,8 +331,8 @@ macro_rules! impl_spaced_input_int {
             fn get_cases(ctx: &CheckCtx) -> (impl Iterator<Item = Self>, u64) {
                 let range0 = int_range(ctx, 0).unwrap_or(full_range());
                 let range1 = int_range(ctx, 1).unwrap_or(full_range());
-                let max_steps0 = iteration_count(ctx, 0);
-                let max_steps1 = iteration_count(ctx, 0);
+                let max_steps0 = arg_max_iterations(ctx, 0);
+                let max_steps1 = arg_max_iterations(ctx, 0);
 
                 if let Some(steps0) = total_value_count_int::<Arg0<Op>>()
                     && steps0 <= max_steps0
diff --git a/library/compiler-builtins/libm-test/src/run_cfg.rs b/library/compiler-builtins/libm-test/src/run_cfg.rs
index 2b42d581b4c9f..234eb914e6d2b 100644
--- a/library/compiler-builtins/libm-test/src/run_cfg.rs
+++ b/library/compiler-builtins/libm-test/src/run_cfg.rs
@@ -15,9 +15,12 @@ pub const EXTENSIVE_ITER_ENV: &str = "LIBM_EXTENSIVE_ITERATIONS";
 
 /// The override value, if set by the above environment.
 static EXTENSIVE_ITER_OVERRIDE: LazyLock<Option<u64>> = LazyLock::new(|| {
-    env::var(EXTENSIVE_ITER_ENV)
-        .map(|v| v.parse().expect("failed to parse iteration count"))
-        .ok()
+    let s = env::var(EXTENSIVE_ITER_ENV).ok()?;
+    let r = match s.as_str() {
+        "unlimited" | "max" => u64::MAX,
+        _ => s.parse().expect("failed to parse iteration count"),
+    };
+    Some(r)
 });
 
 /// Specific tests that need to have a reduced amount of iterations to complete in a reasonable
@@ -236,8 +239,9 @@ fn slow_platform() -> bool {
     slow_on_ci && crate::ci()
 }
 
-/// The number of iterations to run for a given test.
-pub fn iteration_count(ctx: &CheckCtx, argnum: usize) -> u64 {
+/// The maximum number of iterations to run for a given argument in a given test. This may be
+/// greater than the number of representable values.
+pub fn arg_max_iterations(ctx: &CheckCtx, argnum: usize) -> u64 {
     let t_env = TestEnv::from_env(ctx);
 
     // Ideally run 5M tests
@@ -258,52 +262,58 @@ pub fn iteration_count(ctx: &CheckCtx, argnum: usize) -> u64 {
     // Run fewer random tests than domain tests.
     let random_iter_count = domain_iter_count / 100;
 
+    let mut should_adjust = true;
     let mut total_iterations = match ctx.gen_kind {
-        GeneratorKind::Spaced if ctx.extensive => extensive_max_iterations(),
+        GeneratorKind::Spaced if ctx.extensive => {
+            // If an exact number is provided, no need to adjust
+            should_adjust = EXTENSIVE_ITER_OVERRIDE.is_none();
+            extensive_max_iterations()
+        }
         GeneratorKind::Spaced => domain_iter_count,
         GeneratorKind::Random => random_iter_count,
         GeneratorKind::EdgeCases | GeneratorKind::List => {
-            unimplemented!("shoudn't need `iteration_count` for {:?}", ctx.gen_kind)
+            unimplemented!("shoudn't need `arg_max_iterations` for {:?}", ctx.gen_kind)
         }
     };
 
-    // This signature has too many possible inputs to test exhaustively, so increase input count
-    // on all other kinds of tests to get better coverage.
-    if t_env.total_input_bits > MAX_REASONABLE_EXHAUSTIVE_BITS {
-        if ctx.extensive {
-            // Extensive already has a pretty high test count.
-            total_iterations *= 2;
-        } else {
-            total_iterations *= 4;
+    // Apply some adjustments so tests with more possible inputs (argument count or larger float
+    // types) get more tests.
+    if should_adjust {
+        // This signature has too many possible inputs to test exhaustively, so increase input count
+        // on all other kinds of tests to get better coverage.
+        if t_env.total_input_bits > MAX_REASONABLE_EXHAUSTIVE_BITS {
+            if ctx.extensive {
+                // Extensive already has a pretty high test count.
+                total_iterations *= 2;
+            } else {
+                total_iterations *= 4;
+            }
         }
-    }
 
-    // Functions with more arguments get more iterations.
-    let arg_multiplier = 1 << (t_env.input_count - 1);
-    total_iterations *= arg_multiplier;
+        // Functions with more arguments get more iterations.
+        let arg_multiplier = 1 << (t_env.input_count - 1);
+        total_iterations *= arg_multiplier;
 
-    // FMA has a huge domain but is reasonably fast to run, so increase another 1.5x.
-    if ctx.base_name == BaseName::Fma {
-        total_iterations = 3 * total_iterations / 2;
-    }
+        // FMA has a huge domain but is reasonably fast to run, so increase another 1.5x.
+        if ctx.base_name == BaseName::Fma {
+            total_iterations = 3 * total_iterations / 2;
+        }
 
-    // Some tests are significantly slower than others and need to be further reduced.
-    if let Some(slow) = EXTREMELY_SLOW_TESTS
-        .iter()
-        .find(|slow| slow.matches_ctx(ctx))
-    {
-        // However, do not override if the extensive iteration count has been manually set.
-        if !(ctx.extensive && EXTENSIVE_ITER_OVERRIDE.is_some()) {
+        // Some tests are significantly slower than others and need to be further reduced.
+        if let Some(slow) = EXTREMELY_SLOW_TESTS
+            .iter()
+            .find(|slow| slow.matches_ctx(ctx))
+        {
             total_iterations /= slow.reduce_factor;
         }
-    }
 
-    if cfg!(optimizations_enabled) {
-        // Always run at least 10,000 tests.
-        total_iterations = total_iterations.max(10_000);
-    } else {
-        // Without optimizations, just run a quick check regardless of other parameters.
-        total_iterations = 800;
+        if cfg!(optimizations_enabled) {
+            // Always run at least 10,000 tests.
+            total_iterations = total_iterations.max(10_000);
+        } else {
+            // Without optimizations, just run a quick check regardless of other parameters.
+            total_iterations = 800;
+        }
     }
 
     let mut overridden = false;
@@ -312,7 +322,7 @@ pub fn iteration_count(ctx: &CheckCtx, argnum: usize) -> u64 {
         overridden = true;
     }
 
-    // Adjust for the number of inputs
+    // Distribute available iterations among inputs.
     let ntests = match t_env.input_count {
         1 => total_iterations,
         2 => (total_iterations as f64).sqrt().ceil() as u64,
@@ -320,7 +330,7 @@ pub fn iteration_count(ctx: &CheckCtx, argnum: usize) -> u64 {
         _ => panic!("test has more than three arguments"),
     };
 
-    let total = ntests.pow(t_env.input_count.try_into().unwrap());
+    let total = ntests.saturating_pow(t_env.input_count.try_into().unwrap());
 
     let seed_msg = match ctx.gen_kind {
         GeneratorKind::Spaced => String::new(),
diff --git a/library/compiler-builtins/libm/Cargo.toml b/library/compiler-builtins/libm/Cargo.toml
index 8d7fe9515e4d1..f9dbd29ffc3ea 100644
--- a/library/compiler-builtins/libm/Cargo.toml
+++ b/library/compiler-builtins/libm/Cargo.toml
@@ -16,7 +16,7 @@ edition = "2021"
 rust-version = "1.67"
 
 [dev-dependencies]
-# FIXME(msrv): switch to `no-panic.workspace` when possible
+# FIXME(msrv>=1.85): switch to `no-panic.workspace`
 no-panic = "0.1.36"
 
 [features]
diff --git a/library/compiler-builtins/libm/src/lib.rs b/library/compiler-builtins/libm/src/lib.rs
index 85ed5e2c9fc63..9c323347a04dd 100644
--- a/library/compiler-builtins/libm/src/lib.rs
+++ b/library/compiler-builtins/libm/src/lib.rs
@@ -1,5 +1,6 @@
 //! libm in pure Rust
 #![no_std]
+//
 #![cfg_attr(intrinsics_enabled, allow(internal_features))]
 #![cfg_attr(intrinsics_enabled, feature(core_intrinsics))]
 #![cfg_attr(
@@ -8,21 +9,26 @@
 )]
 #![cfg_attr(f128_enabled, feature(f128))]
 #![cfg_attr(f16_enabled, feature(f16))]
-#![allow(unstable_name_collisions)] // FIXME(float_bits_const): remove when stable
+//
+// The edition is 2021 but we follow 2024 idioms.
+#![deny(rust_2024_compatibility)]
+#![allow(edition_2024_expr_fragment_specifier)]
+//
+// FIXME(float_bits_const): remove when stable
+#![allow(unstable_name_collisions)]
+// Allow idioms that come from ported C or may be more clear
 #![allow(clippy::assign_op_pattern)]
-#![allow(clippy::deprecated_cfg_attr)]
-#![allow(clippy::eq_op)]
-#![allow(clippy::excessive_precision)]
-#![allow(clippy::float_cmp)]
 #![allow(clippy::int_plus_one)]
-#![allow(clippy::just_underscores_and_digits)]
-#![allow(clippy::many_single_char_names)]
-#![allow(clippy::mixed_case_hex_literals)]
 #![allow(clippy::needless_late_init)]
 #![allow(clippy::needless_return)]
-#![allow(clippy::unreadable_literal)]
+// Literals are usually intentional
+#![allow(clippy::excessive_precision)]
+// Allow needed patterns like `(z - z) / (z - z)` and `0.0 / 0.0` that we need for exceptions
+// and rounding.
+#![allow(clippy::eq_op)]
 #![allow(clippy::zero_divided_by_zero)]
-#![forbid(unsafe_op_in_unsafe_fn)]
+// In generic code we use bits like `let _0 = F::ZERO`
+#![allow(clippy::just_underscores_and_digits)]
 
 mod libm_helper;
 mod math;
diff --git a/library/compiler-builtins/libm/src/math/arch/loongarch/fma.rs b/library/compiler-builtins/libm/src/math/arch/loongarch/fma.rs
new file mode 100644
index 0000000000000..8ea24ea6954ff
--- /dev/null
+++ b/library/compiler-builtins/libm/src/math/arch/loongarch/fma.rs
@@ -0,0 +1,31 @@
+use core::arch::asm;
+
+#[cfg(target_feature = "d")]
+pub fn fma(mut x: f64, y: f64, z: f64) -> f64 {
+    // SAFETY: `fmadd.d` is available with `d and has no side effects.
+    unsafe {
+        asm!(
+            "fmadd.d {x}, {x}, {y}, {z}",
+            x = inout(freg) x,
+            y = in(freg) y,
+            z = in(freg) z,
+            options(nomem, nostack, pure)
+        );
+    }
+    x
+}
+
+#[cfg(target_feature = "f")]
+pub fn fmaf(mut x: f32, y: f32, z: f32) -> f32 {
+    // SAFETY: `fmadd.s` is available with `f` and has no side effects.
+    unsafe {
+        asm!(
+            "fmadd.s {x}, {x}, {y}, {z}",
+            x = inout(freg) x,
+            y = in(freg) y,
+            z = in(freg) z,
+            options(nomem, nostack, pure)
+        );
+    }
+    x
+}
diff --git a/library/compiler-builtins/libm/src/math/arch/loongarch/mod.rs b/library/compiler-builtins/libm/src/math/arch/loongarch/mod.rs
new file mode 100644
index 0000000000000..90c61e30ec067
--- /dev/null
+++ b/library/compiler-builtins/libm/src/math/arch/loongarch/mod.rs
@@ -0,0 +1,16 @@
+//! Architecture-specific support for LoongArch with FPU
+
+mod fma;
+mod rounding;
+mod sqrt;
+
+#[cfg(target_feature = "d")]
+pub use fma::fma;
+#[cfg(target_feature = "f")]
+pub use fma::fmaf;
+#[cfg(target_feature = "lsx")]
+pub use rounding::{rint, rintf};
+#[cfg(target_feature = "d")]
+pub use sqrt::sqrt;
+#[cfg(target_feature = "f")]
+pub use sqrt::sqrtf;
diff --git a/library/compiler-builtins/libm/src/math/arch/loongarch/rounding.rs b/library/compiler-builtins/libm/src/math/arch/loongarch/rounding.rs
new file mode 100644
index 0000000000000..ebbef09fea127
--- /dev/null
+++ b/library/compiler-builtins/libm/src/math/arch/loongarch/rounding.rs
@@ -0,0 +1,39 @@
+//! NB: `frint.{s.d}` is technically the correct instruction for C's `rint`.
+//! However, in Rust (and LLVM by default), `rint` is identical to `roundeven`
+//! (no fpenv interaction) so we use the side-effect-free `vfrintrne.{s,d}`.
+//!
+//! In general, C code that calls Rust's libm should assume that fpenv is ignored.
+
+use core::arch::asm;
+
+#[cfg(target_feature = "lsx")]
+pub fn rint(mut x: f64) -> f64 {
+    // SAFETY: `vfrintrne.d` is available with `lsx` and has no side effects.
+    //
+    // `vfrintrne.d` is always round-to-nearest which does not match the
+    // C specification, but Rust does not support rounding modes.
+    unsafe {
+        asm!(
+            "vfrintrne.d {x:w}, {x:w}",
+            x = inout(freg) x,
+            options(nomem, nostack, pure)
+        );
+    }
+    x
+}
+
+#[cfg(target_feature = "lsx")]
+pub fn rintf(mut x: f32) -> f32 {
+    // SAFETY: `vfrintrne.s` is available with `lsx` and has no side effects.
+    //
+    // `vfrintrne.s` is always round-to-nearest which does not match the
+    // C specification, but Rust does not support rounding modes.
+    unsafe {
+        asm!(
+            "vfrintrne.s {x:w}, {x:w}",
+            x = inout(freg) x,
+            options(nomem, nostack, pure)
+        );
+    }
+    x
+}
diff --git a/library/compiler-builtins/libm/src/math/arch/loongarch/sqrt.rs b/library/compiler-builtins/libm/src/math/arch/loongarch/sqrt.rs
new file mode 100644
index 0000000000000..e23d3facc0375
--- /dev/null
+++ b/library/compiler-builtins/libm/src/math/arch/loongarch/sqrt.rs
@@ -0,0 +1,27 @@
+use core::arch::asm;
+
+#[cfg(target_feature = "d")]
+pub fn sqrt(mut x: f64) -> f64 {
+    // SAFETY: `fsqrt.d` is available with `d` and has no side effects.
+    unsafe {
+        asm!(
+            "fsqrt.d {x}, {x}",
+            x = inout(freg) x,
+            options(nomem, nostack, pure)
+        );
+    }
+    x
+}
+
+#[cfg(target_feature = "f")]
+pub fn sqrtf(mut x: f32) -> f32 {
+    // SAFETY: `fsqrt.s` is available with `f` and has no side effects.
+    unsafe {
+        asm!(
+            "fsqrt.s {x}, {x}",
+            x = inout(freg) x,
+            options(nomem, nostack, pure)
+        );
+    }
+    x
+}
diff --git a/library/compiler-builtins/libm/src/math/arch/mod.rs b/library/compiler-builtins/libm/src/math/arch/mod.rs
index 1bed464cfa7d6..ab2c4a17760b4 100644
--- a/library/compiler-builtins/libm/src/math/arch/mod.rs
+++ b/library/compiler-builtins/libm/src/math/arch/mod.rs
@@ -6,21 +6,24 @@
 //! well as improving things when these routines are called as part of other implementations.
 
 // Most implementations should be defined here, to ensure they are not made available when
-// soft floats are required.
-#[cfg(feature = "arch")]
-cfg_if! {
-    if #[cfg(all(target_arch = "wasm32", intrinsics_enabled))] {
+// soft floats are required. Primarily gated on the `arch` feature, Miri does not support inline
+// assembly.
+#[cfg(all(feature = "arch", not(miri)))]
+cfg_select_nofmt! {
+    all(target_arch = "wasm32", intrinsics_enabled) => {
         mod wasm32;
         pub use wasm32::{
             ceil, ceilf, fabs, fabsf, floor, floorf, rint, rintf, sqrt, sqrtf, trunc, truncf,
         };
-    } else if #[cfg(target_feature = "sse2")] {
+    }
+    target_feature = "sse2" => {
         mod x86;
         pub use x86::{sqrt, sqrtf, fma, fmaf};
-    } else if #[cfg(all(
+    }
+    all(
         any(target_arch = "aarch64", target_arch = "arm64ec"),
         target_feature = "neon"
-    ))] {
+    ) => {
         mod aarch64;
 
         pub use aarch64::{
@@ -38,12 +41,27 @@ cfg_if! {
             sqrtf16,
         };
     }
+    any(target_arch = "loongarch32", target_arch = "loongarch64") => {
+        mod loongarch;
+
+        #[cfg(target_feature = "d")]
+        pub use loongarch::fma;
+        #[cfg(target_feature = "f")]
+        pub use loongarch::fmaf;
+        #[cfg(target_feature = "lsx")]
+        pub use loongarch::{rint, rintf};
+        #[cfg(target_feature = "d")]
+        pub use loongarch::sqrt;
+        #[cfg(target_feature = "f")]
+        pub use loongarch::sqrtf;
+    }
+    _ => {}
 }
 
 // There are certain architecture-specific implementations that are needed for correctness
 // even with `arch` disabled. These are configured here.
-cfg_if! {
-    if #[cfg(x86_no_sse2)] {
+cfg_select_nofmt! {
+    x86_no_sse2 => {
         mod i586;
         pub use i586::{
             ceil,
@@ -57,4 +75,5 @@ cfg_if! {
             x87_expf,
         };
     }
+    _ => {}
 }
diff --git a/library/compiler-builtins/libm/src/math/fdim.rs b/library/compiler-builtins/libm/src/math/fdim.rs
index dac409e86b135..b61630847f808 100644
--- a/library/compiler-builtins/libm/src/math/fdim.rs
+++ b/library/compiler-builtins/libm/src/math/fdim.rs
@@ -2,8 +2,8 @@
 ///
 /// Determines the positive difference between arguments, returning:
 /// * x - y if x > y, or
-/// * +0    if x <= y, or
-/// * NAN   if either argument is NAN.
+/// * +0 if x <= y, or
+/// * NAN if either argument is NAN.
 ///
 /// A range error may occur.
 #[cfg(f16_enabled)]
@@ -16,8 +16,8 @@ pub fn fdimf16(x: f16, y: f16) -> f16 {
 ///
 /// Determines the positive difference between arguments, returning:
 /// * x - y if x > y, or
-/// * +0    if x <= y, or
-/// * NAN   if either argument is NAN.
+/// * +0 if x <= y, or
+/// * NAN if either argument is NAN.
 ///
 /// A range error may occur.
 #[cfg_attr(assert_no_panic, no_panic::no_panic)]
@@ -29,8 +29,8 @@ pub fn fdimf(x: f32, y: f32) -> f32 {
 ///
 /// Determines the positive difference between arguments, returning:
 /// * x - y if x > y, or
-/// * +0    if x <= y, or
-/// * NAN   if either argument is NAN.
+/// * +0 if x <= y, or
+/// * NAN if either argument is NAN.
 ///
 /// A range error may occur.
 #[cfg_attr(assert_no_panic, no_panic::no_panic)]
@@ -42,8 +42,8 @@ pub fn fdim(x: f64, y: f64) -> f64 {
 ///
 /// Determines the positive difference between arguments, returning:
 /// * x - y if x > y, or
-/// * +0    if x <= y, or
-/// * NAN   if either argument is NAN.
+/// * +0 if x <= y, or
+/// * NAN if either argument is NAN.
 ///
 /// A range error may occur.
 #[cfg(f128_enabled)]
@@ -51,3 +51,101 @@ pub fn fdim(x: f64, y: f64) -> f64 {
 pub fn fdimf128(x: f128, y: f128) -> f128 {
     super::generic::fdim(x, y)
 }
+
+#[cfg(test)]
+mod tests {
+    use crate::support::{Float, Hex};
+
+    macro_rules! cases {
+        ($f:ty) => {
+            [
+                // x = -inf
+                (<$f>::NEG_INFINITY, <$f>::NEG_INFINITY, 0.0),
+                (<$f>::NEG_INFINITY, -1.0, 0.0),
+                (<$f>::NEG_INFINITY, -0.0, 0.0),
+                (<$f>::NEG_INFINITY, 0.0, 0.0),
+                (<$f>::NEG_INFINITY, 1.0, 0.0),
+                (<$f>::NEG_INFINITY, <$f>::INFINITY, 0.0),
+                (<$f>::NEG_INFINITY, <$f>::NAN, <$f>::NAN),
+                // x = -1.0
+                (-1.0, <$f>::NEG_INFINITY, <$f>::INFINITY),
+                (-1.0, -1.0, 0.0),
+                (-1.0, -0.0, 0.0),
+                (-1.0, 0.0, 0.0),
+                (-1.0, 1.0, 0.0),
+                (-1.0, <$f>::INFINITY, 0.0),
+                (-1.0, <$f>::NAN, <$f>::NAN),
+                // x = -0.0
+                (-0.0, <$f>::NEG_INFINITY, <$f>::INFINITY),
+                (-0.0, -1.0, 1.0),
+                (-0.0, -0.0, 0.0),
+                (-0.0, 0.0, 0.0),
+                (-0.0, 1.0, 0.0),
+                (-0.0, <$f>::INFINITY, 0.0),
+                (-0.0, <$f>::NAN, <$f>::NAN),
+                // x = 0.0
+                (0.0, <$f>::NEG_INFINITY, <$f>::INFINITY),
+                (0.0, -1.0, 1.0),
+                (0.0, -0.0, 0.0),
+                (0.0, 0.0, 0.0),
+                (0.0, 1.0, 0.0),
+                (0.0, <$f>::INFINITY, 0.0),
+                (0.0, <$f>::NAN, <$f>::NAN),
+                // x = 1.0
+                (1.0, <$f>::NEG_INFINITY, <$f>::INFINITY),
+                (1.0, -1.0, 2.0),
+                (1.0, -0.0, 1.0),
+                (1.0, 0.0, 1.0),
+                (1.0, 1.0, 0.0),
+                (1.0, <$f>::INFINITY, 0.0),
+                (1.0, <$f>::NAN, <$f>::NAN),
+                // x = inf
+                (<$f>::INFINITY, <$f>::NEG_INFINITY, <$f>::INFINITY),
+                (<$f>::INFINITY, -1.0, <$f>::INFINITY),
+                (<$f>::INFINITY, -0.0, <$f>::INFINITY),
+                (<$f>::INFINITY, 0.0, <$f>::INFINITY),
+                (<$f>::INFINITY, 1.0, <$f>::INFINITY),
+                (<$f>::INFINITY, <$f>::INFINITY, 0.0),
+                (<$f>::INFINITY, <$f>::NAN, <$f>::NAN),
+                // x = nan
+                (<$f>::NAN, <$f>::NEG_INFINITY, <$f>::NAN),
+                (<$f>::NAN, -1.0, <$f>::NAN),
+                (<$f>::NAN, -0.0, <$f>::NAN),
+                (<$f>::NAN, 0.0, <$f>::NAN),
+                (<$f>::NAN, 1.0, <$f>::NAN),
+                (<$f>::NAN, <$f>::INFINITY, <$f>::NAN),
+                (<$f>::NAN, <$f>::NAN, <$f>::NAN),
+            ]
+        };
+    }
+
+    #[track_caller]
+    fn check<F: Float>(f: fn(F, F) -> F, cases: &[(F, F, F)]) {
+        for &(x, y, exp_res) in cases {
+            let val = f(x, y);
+            assert_biteq!(val, exp_res, "fdim({x:?}, {y:?}) ({} {})", Hex(x), Hex(y));
+        }
+    }
+
+    #[test]
+    #[cfg(f16_enabled)]
+    fn check_f16() {
+        check::<f16>(super::super::fdimf16, &cases!(f16));
+    }
+
+    #[test]
+    fn check_f32() {
+        check::<f32>(super::super::fdimf, &cases!(f32));
+    }
+
+    #[test]
+    fn check_f64() {
+        check::<f64>(super::super::fdim, &cases!(f64));
+    }
+
+    #[test]
+    #[cfg(f128_enabled)]
+    fn check_f128() {
+        check::<f128>(super::super::fdimf128, &cases!(f128));
+    }
+}
diff --git a/library/compiler-builtins/libm/src/math/fma.rs b/library/compiler-builtins/libm/src/math/fma.rs
index 513921d530faf..e6b9e8fa1b60b 100644
--- a/library/compiler-builtins/libm/src/math/fma.rs
+++ b/library/compiler-builtins/libm/src/math/fma.rs
@@ -1,6 +1,3 @@
-/* SPDX-License-Identifier: MIT */
-/* origin: musl src/math/fma.c, fmaf.c Ported to generic Rust algorithm in 2025, TG. */
-
 use super::generic;
 use crate::support::Round;
 
@@ -15,6 +12,7 @@ pub fn fmaf(x: f32, y: f32, z: f32) -> f32 {
         name: fmaf,
         use_arch: any(
             all(target_arch = "aarch64", target_feature = "neon"),
+            all(any(target_arch = "loongarch32", target_arch = "loongarch64"), target_feature = "f"),
             target_feature = "sse2",
         ),
         args: x, y, z,
@@ -32,6 +30,7 @@ pub fn fma(x: f64, y: f64, z: f64) -> f64 {
         name: fma,
         use_arch: any(
             all(target_arch = "aarch64", target_feature = "neon"),
+            all(any(target_arch = "loongarch32", target_arch = "loongarch64"), target_feature = "d"),
             target_feature = "sse2",
         ),
         args: x, y, z,
diff --git a/library/compiler-builtins/libm/src/math/generic/fma_wide.rs b/library/compiler-builtins/libm/src/math/generic/fma_wide.rs
index a2ef59d3e3d6f..e7d540694135d 100644
--- a/library/compiler-builtins/libm/src/math/generic/fma_wide.rs
+++ b/library/compiler-builtins/libm/src/math/generic/fma_wide.rs
@@ -1,5 +1,8 @@
+/* SPDX-License-Identifier: MIT */
+/* origin: musl src/math/fmaf.c Ported to generic Rust algorithm in 2025, TG. */
+
 use crate::support::{
-    CastFrom, CastInto, DFloat, Float, FpResult, HFloat, IntTy, MinInt, Round, Status,
+    CastFrom, CastInto, Float, FpResult, IntTy, MinInt, NarrowFloat, Round, Status, WideFloat,
 };
 
 /// Fma implementation when a hardware-backed larger float type is available. For `f32` and `f64`,
@@ -7,8 +10,8 @@ use crate::support::{
 #[inline]
 pub fn fma_wide_round<F, B>(x: F, y: F, z: F, round: Round) -> FpResult<F>
 where
-    F: Float + HFloat<D = B>,
-    B: Float + DFloat<H = F>,
+    F: Float + NarrowFloat<D = B>,
+    B: Float + WideFloat<H = F>,
     B::Int: CastInto<i32>,
     i32: CastFrom<i32>,
 {
diff --git a/library/compiler-builtins/libm/src/math/lgammaf_r.rs b/library/compiler-builtins/libm/src/math/lgammaf_r.rs
index 5c087f14d7df2..9e60bb267cb77 100644
--- a/library/compiler-builtins/libm/src/math/lgammaf_r.rs
+++ b/library/compiler-builtins/libm/src/math/lgammaf_r.rs
@@ -178,7 +178,7 @@ pub fn lgammaf_r(mut x: f32) -> (f32, i32) {
                 /* [1.7316,2] */
                 y = 2.0 - x;
                 i = 0;
-            } else if ix >= 0x3F9da620 {
+            } else if ix >= 0x3f9da620 {
                 /* [1.23,1.73] */
                 y = x - TC;
                 i = 1;
diff --git a/library/compiler-builtins/libm/src/math/mod.rs b/library/compiler-builtins/libm/src/math/mod.rs
index 809d5e5d18092..50b42e0c07972 100644
--- a/library/compiler-builtins/libm/src/math/mod.rs
+++ b/library/compiler-builtins/libm/src/math/mod.rs
@@ -67,15 +67,16 @@ pub mod support;
 #[cfg(not(feature = "unstable-public-internals"))]
 pub(crate) mod support;
 
-cfg_if! {
-    if #[cfg(feature = "unstable-public-internals")] {
+cfg_select_nofmt! {
+    feature = "unstable-public-internals" => {
         pub mod generic;
-    } else {
+    }
+    _ => {
         mod generic;
     }
 }
 
-pub mod approx;
+pub mod relaxed;
 
 // Private modules
 mod arch;
@@ -106,7 +107,9 @@ use self::rem_pio2::rem_pio2;
 use self::rem_pio2_large::rem_pio2_large;
 use self::rem_pio2f::rem_pio2f;
 #[allow(unused_imports)]
-use self::support::{CastFrom, CastInto, DFloat, DInt, Float, HFloat, HInt, Int, IntTy, MinInt};
+use self::support::{
+    CastFrom, CastInto, DInt, Float, HInt, Int, IntTy, MinInt, NarrowFloat, WideFloat,
+};
 
 // Public modules
 mod acos;
@@ -294,8 +297,8 @@ pub use self::tgamma::tgamma;
 pub use self::tgammaf::tgammaf;
 pub use self::trunc::{trunc, truncf};
 
-cfg_if! {
-    if #[cfg(f16_enabled)] {
+cfg_select_nofmt! {
+    f16_enabled => {
         mod fmaf16;
 
         // verify-sorted-start
@@ -320,10 +323,11 @@ cfg_if! {
         pub use self::trunc::truncf16;
         // verify-sorted-end
     }
+    _ => {}
 }
 
-cfg_if! {
-    if #[cfg(f128_enabled)] {
+cfg_select_nofmt! {
+    f128_enabled => {
         // verify-sorted-start
         pub use self::ceil::ceilf128;
         pub use self::copysign::copysignf128;
@@ -346,6 +350,7 @@ cfg_if! {
         pub use self::trunc::truncf128;
         // verify-sorted-end
     }
+    _ => {}
 }
 
 #[inline]
diff --git a/library/compiler-builtins/libm/src/math/approx/cbrtf64.rs b/library/compiler-builtins/libm/src/math/relaxed/cbrtf64.rs
similarity index 100%
rename from library/compiler-builtins/libm/src/math/approx/cbrtf64.rs
rename to library/compiler-builtins/libm/src/math/relaxed/cbrtf64.rs
diff --git a/library/compiler-builtins/libm/src/math/approx/hypot.rs b/library/compiler-builtins/libm/src/math/relaxed/hypotf64.rs
similarity index 95%
rename from library/compiler-builtins/libm/src/math/approx/hypot.rs
rename to library/compiler-builtins/libm/src/math/relaxed/hypotf64.rs
index c0b2a19370cd7..ae4196aefff03 100644
--- a/library/compiler-builtins/libm/src/math/approx/hypot.rs
+++ b/library/compiler-builtins/libm/src/math/relaxed/hypotf64.rs
@@ -1,4 +1,4 @@
-use super::sqrt;
+use super::super::sqrt;
 
 const SPLIT: f64 = 134217728. + 1.; // 0x1p27 + 1 === (2 ^ 27) + 1
 
@@ -16,7 +16,7 @@ fn sq(x: f64) -> (f64, f64) {
 }
 
 #[cfg_attr(assert_no_panic, no_panic::no_panic)]
-pub fn hypot(mut x: f64, mut y: f64) -> f64 {
+pub fn hypotf64(mut x: f64, mut y: f64) -> f64 {
     let x1p700 = f64::from_bits(0x6bb0000000000000); // 0x1p700 === 2 ^ 700
     let x1p_700 = f64::from_bits(0x1430000000000000); // 0x1p-700 === 2 ^ -700
 
diff --git a/library/compiler-builtins/libm/src/math/approx/mod.rs b/library/compiler-builtins/libm/src/math/relaxed/mod.rs
similarity index 66%
rename from library/compiler-builtins/libm/src/math/approx/mod.rs
rename to library/compiler-builtins/libm/src/math/relaxed/mod.rs
index da0d0bf39efc4..ed3b4146249fb 100644
--- a/library/compiler-builtins/libm/src/math/approx/mod.rs
+++ b/library/compiler-builtins/libm/src/math/relaxed/mod.rs
@@ -1,8 +1,10 @@
-//! Approximate implementations.
+//! Relaxed precision implementations.
 //!
 //! These functions may be smaller or faster than those in the main `math` module, but will
 //! not be as accurate.
 
 mod cbrtf64;
+mod hypotf64;
 
 pub use cbrtf64::cbrtf64;
+pub use hypotf64::hypotf64;
diff --git a/library/compiler-builtins/libm/src/math/rint.rs b/library/compiler-builtins/libm/src/math/rint.rs
index 75c46acc0e856..ca3864b1582c9 100644
--- a/library/compiler-builtins/libm/src/math/rint.rs
+++ b/library/compiler-builtins/libm/src/math/rint.rs
@@ -20,6 +20,7 @@ pub fn rintf(x: f32) -> f32 {
         name: rintf,
         use_arch: any(
             all(target_arch = "aarch64", target_feature = "neon"),
+            all(any(target_arch = "loongarch32", target_arch = "loongarch64"), target_feature = "lsx"),
             all(target_arch = "wasm32", intrinsics_enabled),
         ),
         args: x,
@@ -35,6 +36,7 @@ pub fn rint(x: f64) -> f64 {
         name: rint,
         use_arch: any(
             all(target_arch = "aarch64", target_feature = "neon"),
+            all(any(target_arch = "loongarch32", target_arch = "loongarch64"), target_feature = "lsx"),
             all(target_arch = "wasm32", intrinsics_enabled),
         ),
         use_arch_required: x86_no_sse2,
diff --git a/library/compiler-builtins/libm/src/math/sin.rs b/library/compiler-builtins/libm/src/math/sin.rs
index 2f54074c25ef0..ded0df85ad237 100644
--- a/library/compiler-builtins/libm/src/math/sin.rs
+++ b/library/compiler-builtins/libm/src/math/sin.rs
@@ -88,7 +88,7 @@ mod tests {
     #[test]
     #[cfg_attr(x86_no_sse2, ignore = "FIXME(i586): possible incorrect rounding")]
     fn test_near_pi() {
-        let x = f64::from_bits(0x400921fb000FD5DD); // 3.141592026217707
+        let x = f64::from_bits(0x400921fb000fd5dd); // 3.141592026217707
         let sx = f64::from_bits(0x3ea50d15ced1a4a2); // 6.273720864039205e-7
         assert_eq!(sin(x), sx);
     }
diff --git a/library/compiler-builtins/libm/src/math/sqrt.rs b/library/compiler-builtins/libm/src/math/sqrt.rs
index 10edf397a0a0a..a8e2a387661cf 100644
--- a/library/compiler-builtins/libm/src/math/sqrt.rs
+++ b/library/compiler-builtins/libm/src/math/sqrt.rs
@@ -22,6 +22,7 @@ pub fn sqrtf(x: f32) -> f32 {
         use_arch: any(
             all(target_arch = "aarch64", target_feature = "neon"),
             all(target_arch = "wasm32", intrinsics_enabled),
+            all(any(target_arch = "loongarch32", target_arch = "loongarch64"), target_feature = "f"),
             target_feature = "sse2"
         ),
         args: x,
@@ -38,6 +39,7 @@ pub fn sqrt(x: f64) -> f64 {
         use_arch: any(
             all(target_arch = "aarch64", target_feature = "neon"),
             all(target_arch = "wasm32", intrinsics_enabled),
+            all(any(target_arch = "loongarch32", target_arch = "loongarch64"), target_feature = "d"),
             target_feature = "sse2"
         ),
         args: x,
diff --git a/library/compiler-builtins/libm/src/math/support/big.rs b/library/compiler-builtins/libm/src/math/support/big.rs
index c316d93f524ab..9b8728c987cfd 100644
--- a/library/compiler-builtins/libm/src/math/support/big.rs
+++ b/library/compiler-builtins/libm/src/math/support/big.rs
@@ -294,11 +294,12 @@ impl fmt::Debug for i256 {
 
 impl fmt::LowerHex for u256 {
     fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
-        cfg_if! {
-            if #[cfg(feature = "compiler-builtins")] {
+        cfg_select_nofmt! {
+            feature = "compiler-builtins" => {
                 let _ = f;
                 unimplemented!()
-            } else {
+            }
+            _ => {
                 let pfx= if f.alternate() { "0x"} else {""};
                 write!(f, "{pfx}{:032x}{:032x}", self.hi, self.lo)
             }
diff --git a/library/compiler-builtins/libm/src/math/support/big/tests.rs b/library/compiler-builtins/libm/src/math/support/big/tests.rs
index 0ac8f9721a4dd..2f0ba7ebc3182 100644
--- a/library/compiler-builtins/libm/src/math/support/big/tests.rs
+++ b/library/compiler-builtins/libm/src/math/support/big/tests.rs
@@ -488,6 +488,7 @@ fn i256_shifts() {
     }
 }
 #[test]
+#[cfg_attr(miri, ignore)] // This test is very slow when using Miri
 fn div_u256_by_u128() {
     for j in i8::MIN..=i8::MAX {
         let y: u128 = (j as i128).rotate_right(4).unsigned();
diff --git a/library/compiler-builtins/libm/src/math/support/float_traits.rs b/library/compiler-builtins/libm/src/math/support/float_traits.rs
index 7bc9734a20994..f802f4be6c2d7 100644
--- a/library/compiler-builtins/libm/src/math/support/float_traits.rs
+++ b/library/compiler-builtins/libm/src/math/support/float_traits.rs
@@ -337,31 +337,34 @@ macro_rules! float_impl {
                 Self::from_bits(a)
             }
             fn abs(self) -> Self {
-                cfg_if! {
+                cfg_select_nofmt! {
                     // FIXME(msrv): `abs` is available in `core` starting with 1.85.
-                    if #[cfg(intrinsics_enabled)] {
+                    intrinsics_enabled => {
                         self.abs()
-                    } else {
+                    }
+                    _ => {
                         super::super::generic::fabs(self)
                     }
                 }
             }
             fn copysign(self, other: Self) -> Self {
-                cfg_if! {
+                cfg_select_nofmt! {
                     // FIXME(msrv): `copysign` is available in `core` starting with 1.85.
-                    if #[cfg(intrinsics_enabled)] {
+                    intrinsics_enabled => {
                         self.copysign(other)
-                    } else {
+                    }
+                    _ => {
                         super::super::generic::copysign(self, other)
                     }
                 }
             }
             fn fma(self, y: Self, z: Self) -> Self {
-                cfg_if! {
+                cfg_select_nofmt! {
                     // fma is not yet available in `core`
-                    if #[cfg(intrinsics_enabled)] {
+                    intrinsics_enabled => {
                         core::intrinsics::$fma_intrinsic(self, y, z)
-                    } else {
+                    }
+                    _ => {
                         super::super::$fma_fn(self, y, z)
                     }
                 }
@@ -453,28 +456,28 @@ pub const fn f64_to_bits(x: f64) -> u64 {
     unsafe { mem::transmute::<f64, u64>(x) }
 }
 
-/// Trait for floats twice the bit width of another integer.
-pub trait DFloat: Float {
+/// Trait for floats that are wider than a `NFloat` type.
+pub trait WideFloat: Float {
     /// Float that is half the bit width of the floatthis trait is implemented for.
-    type H: HFloat<D = Self>;
+    type H: NarrowFloat<D = Self>;
 
     /// Narrow the float type.
     fn narrow(self) -> Self::H;
 }
 
-/// Trait for floats half the bit width of another float.
-pub trait HFloat: Float {
+/// Trait for floats narrower than a `WFloat` type.
+pub trait NarrowFloat: Float {
     /// Float that is double the bit width of the float this trait is implemented for.
-    type D: DFloat<H = Self>;
+    type D: WideFloat<H = Self>;
 
     /// Widen the float type.
     fn widen(self) -> Self::D;
 }
 
-macro_rules! impl_d_float {
+macro_rules! impl_wide_float {
     ($($X:ident $D:ident),*) => {
         $(
-            impl DFloat for $D {
+            impl WideFloat for $D {
                 type H = $X;
 
                 fn narrow(self) -> Self::H {
@@ -485,10 +488,10 @@ macro_rules! impl_d_float {
     };
 }
 
-macro_rules! impl_h_float {
+macro_rules! impl_narrow_float {
     ($($H:ident $X:ident),*) => {
         $(
-            impl HFloat for $H {
+            impl NarrowFloat for $H {
                 type D = $X;
 
                 fn widen(self) -> Self::D {
@@ -499,17 +502,17 @@ macro_rules! impl_h_float {
     };
 }
 
-impl_d_float!(f32 f64);
+impl_wide_float!(f32 f64);
 #[cfg(f16_enabled)]
-impl_d_float!(f16 f32);
+impl_wide_float!(f16 f32);
 #[cfg(f128_enabled)]
-impl_d_float!(f64 f128);
+impl_wide_float!(f64 f128);
 
-impl_h_float!(f32 f64);
+impl_narrow_float!(f32 f64);
 #[cfg(f16_enabled)]
-impl_h_float!(f16 f32);
+impl_narrow_float!(f16 f32);
 #[cfg(f128_enabled)]
-impl_h_float!(f64 f128);
+impl_narrow_float!(f64 f128);
 
 #[cfg(test)]
 mod tests {
diff --git a/library/compiler-builtins/libm/src/math/support/hex_float.rs b/library/compiler-builtins/libm/src/math/support/hex_float.rs
index e1100a4a119f0..607ba7964023b 100644
--- a/library/compiler-builtins/libm/src/math/support/hex_float.rs
+++ b/library/compiler-builtins/libm/src/math/support/hex_float.rs
@@ -448,11 +448,12 @@ mod hex_fmt {
     // Not really a meaningful impl, but makes some generics easier.
     impl DisplayHex for bool {
         fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
-            cfg_if! {
-                if #[cfg(feature = "compiler-builtins")] {
+            cfg_select_nofmt! {
+                feature = "compiler-builtins" => {
                     let _ = f;
                     unimplemented!()
-                } else {
+                }
+                _ => {
                     write!(f, "{self}")
                 }
             }
@@ -585,6 +586,7 @@ mod parse_tests {
     }
 
     #[test]
+    #[cfg_attr(miri, ignore)] // This test is very slow when using Miri
     fn test_parse_any() {
         for k in -149..=127 {
             let s = format!("0x1p{k}");
@@ -676,6 +678,7 @@ mod parse_tests {
         }
     }
     #[test]
+    #[cfg_attr(miri, ignore)] // This test is very slow when using Miri
     fn long_tail() {
         for k in 1..1000 {
             let s = format!("0x1.{}p0", "0".repeat(k));
diff --git a/library/compiler-builtins/libm/src/math/support/int_traits.rs b/library/compiler-builtins/libm/src/math/support/int_traits.rs
index f113f9d62d143..48c0e0438bc1d 100644
--- a/library/compiler-builtins/libm/src/math/support/int_traits.rs
+++ b/library/compiler-builtins/libm/src/math/support/int_traits.rs
@@ -110,6 +110,7 @@ pub trait Int:
     fn borrowing_sub(self, other: Self, borrow: bool) -> (Self, bool);
     fn leading_zeros(self) -> u32;
     fn trailing_zeros(self) -> u32;
+    fn count_ones(self) -> u32;
     fn ilog2(self) -> u32;
 }
 
@@ -179,6 +180,10 @@ macro_rules! int_impl_common {
             <Self>::trailing_zeros(self)
         }
 
+        fn count_ones(self) -> u32 {
+            <Self>::count_ones(self)
+        }
+
         fn ilog2(self) -> u32 {
             // On our older MSRV, this resolves to the trait method. Which won't actually work,
             // but this is only called behind other gates.
diff --git a/library/compiler-builtins/libm/src/math/support/int_traits/narrowing_div.rs b/library/compiler-builtins/libm/src/math/support/int_traits/narrowing_div.rs
index e76fc5ae9f4ca..942cd5ed2acc0 100644
--- a/library/compiler-builtins/libm/src/math/support/int_traits/narrowing_div.rs
+++ b/library/compiler-builtins/libm/src/math/support/int_traits/narrowing_div.rs
@@ -153,6 +153,7 @@ mod test {
     use super::{HInt, NarrowingDiv};
 
     #[test]
+    #[cfg_attr(miri, ignore)] // This test is very slow when using Miri
     fn inverse_mul() {
         for x in 0..=u8::MAX {
             for y in 1..=u8::MAX {
diff --git a/library/compiler-builtins/libm/src/math/support/macros.rs b/library/compiler-builtins/libm/src/math/support/macros.rs
index f1bfa21eec7f7..767f15a1c14a3 100644
--- a/library/compiler-builtins/libm/src/math/support/macros.rs
+++ b/library/compiler-builtins/libm/src/math/support/macros.rs
@@ -1,67 +1,28 @@
-/// `libm` cannot have dependencies, so this is vendored directly from the `cfg-if` crate
-/// (with some comments stripped for compactness).
-macro_rules! cfg_if {
-    (
-        if #[cfg( $($i_meta:tt)+ )] { $( $i_tokens:tt )* }
-        $(
-            else if #[cfg( $($ei_meta:tt)+ )] { $( $ei_tokens:tt )* }
-        )*
-        $(
-            else { $( $e_tokens:tt )* }
-        )?
-    ) => {
-        cfg_if! {
-            @__items () ;
-            (( $($i_meta)+ ) ( $( $i_tokens )* )),
-            $(
-                (( $($ei_meta)+ ) ( $( $ei_tokens )* )),
-            )*
-            $(
-                (() ( $( $e_tokens )* )),
-            )?
-        }
+// Because `cfg_select` requires rust verion 1.95 and we support older versions,
+// we use the following replacement until that is no longer true.
+//
+// Doesn't support the syntax that rustfmt changes to, hence not calling it just
+// `cfg_seelect`.
+//
+// FIXME(msrv)
+macro_rules! cfg_select_nofmt {
+    ({ $($tt:tt)* }) => {{
+        $crate::cfg_select_nofmt! { $($tt)* }
+    }};
+    (_ => { $($output:tt)* }) => {
+        $($output)*
     };
-
-    // Internal and recursive macro to emit all the items
-    //
-    // Collects all the previous cfgs in a list at the beginning, so they can be
-    // negated. After the semicolon are all the remaining items.
-    (@__items ( $( ($($_:tt)*) , )* ) ; ) => {};
     (
-        @__items ( $( ($($no:tt)+) , )* ) ;
-        (( $( $($yes:tt)+ )? ) ( $( $tokens:tt )* )),
-        $( $rest:tt , )*
+        $cfg:meta => $output:tt
+        $($( $rest:tt )+)?
     ) => {
-        // Emit all items within one block, applying an appropriate #[cfg]. The
-        // #[cfg] will require all `$yes` matchers specified and must also negate
-        // all previous matchers.
-        #[cfg(all(
-            $( $($yes)+ , )?
-            not(any( $( $($no)+ ),* ))
-        ))]
-        // Subtle: You might think we could put `$( $tokens )*` here. But if
-        // that contains multiple items then the `#[cfg(all(..))]` above would
-        // only apply to the first one. By wrapping `$( $tokens )*` in this
-        // macro call, we temporarily group the items into a single thing (the
-        // macro call) that will be included/excluded by the `#[cfg(all(..))]`
-        // as appropriate. If the `#[cfg(all(..))]` succeeds, the macro call
-        // will be included, and then evaluated, producing `$( $tokens )*`. See
-        // also the "issue #90" test below.
-        cfg_if! { @__temp_group $( $tokens )* }
-
-        // Recurse to emit all other items in `$rest`, and when we do so add all
-        // our `$yes` matchers to the list of `$no` matchers as future emissions
-        // will have to negate everything we just matched as well.
-        cfg_if! {
-            @__items ( $( ($($no)+) , )* $( ($($yes)+) , )? ) ;
-            $( $rest , )*
-        }
-    };
-
-    // See the "Subtle" comment above.
-    (@__temp_group $( $tokens:tt )* ) => {
-        $( $tokens )*
-    };
+        #[cfg($cfg)]
+        cfg_select_nofmt! { _ => $output }
+        $(
+            #[cfg(not($cfg))]
+            cfg_select_nofmt! { $($rest)+ }
+        )?
+    }
 }
 
 /// Choose between using an arch-specific implementation and the function body. Returns directly
@@ -96,8 +57,9 @@ macro_rules! select_implementation {
             }
         }
 
-        // By default, never use arch-specific implementations if `arch` is disabled.
-        #[cfg(feature = "arch")]
+        // By default, never use arch-specific implementations if `arch` is disabled or with Miri
+        // (no inline assembly support).
+        #[cfg(all(feature = "arch", not(miri)))]
         select_implementation! {
             @cfg $($use_arch)?;
             // Wrap in `if true` to avoid unused warnings
diff --git a/library/compiler-builtins/libm/src/math/support/mod.rs b/library/compiler-builtins/libm/src/math/support/mod.rs
index 61999a1f94059..260c37080c981 100644
--- a/library/compiler-builtins/libm/src/math/support/mod.rs
+++ b/library/compiler-builtins/libm/src/math/support/mod.rs
@@ -14,10 +14,10 @@ mod modular;
 pub use big::{i256, u256};
 // Clippy seems to have a false positive
 #[allow(unused_imports, clippy::single_component_path_imports)]
-pub(crate) use cfg_if;
+pub(crate) use cfg_select_nofmt;
 pub use env::{FpResult, Round, Status};
 #[allow(unused_imports)]
-pub use float_traits::{DFloat, Float, HFloat, HalfRep, IntTy};
+pub use float_traits::{Float, HalfRep, IntTy, NarrowFloat, WideFloat};
 pub(crate) use float_traits::{f32_from_bits, f64_from_bits};
 #[cfg(f16_enabled)]
 #[allow(unused_imports)]
@@ -40,8 +40,8 @@ pub fn cold_path() {
 ///
 /// `y` must not be zero and the result must not overflow (`x > i32::MIN`).
 pub unsafe fn unchecked_div_i32(x: i32, y: i32) -> i32 {
-    cfg_if! {
-        if #[cfg(all(not(debug_assertions), intrinsics_enabled))] {
+    cfg_select_nofmt! {
+        all(not(debug_assertions), intrinsics_enabled) => {
             // Temporary macro to avoid panic codegen for division (in debug mode too). At
             // the time of this writing this is only used in a few places, and once
             // rust-lang/rust#72751 is fixed then this macro will no longer be necessary and
@@ -50,7 +50,8 @@ pub unsafe fn unchecked_div_i32(x: i32, y: i32) -> i32 {
             // Note: I am not sure whether the above comment is still up to date, we need
             // to double check whether panics are elided where we use this.
             unsafe { core::intrinsics::unchecked_div(x, y) }
-        } else {
+        }
+        _ => {
             x / y
         }
     }
@@ -60,10 +61,11 @@ pub unsafe fn unchecked_div_i32(x: i32, y: i32) -> i32 {
 ///
 /// `y` must not be zero and the result must not overflow (`x > isize::MIN`).
 pub unsafe fn unchecked_div_isize(x: isize, y: isize) -> isize {
-    cfg_if! {
-        if #[cfg(all(not(debug_assertions), intrinsics_enabled))] {
+    cfg_select_nofmt! {
+        all(not(debug_assertions), intrinsics_enabled) => {
             unsafe { core::intrinsics::unchecked_div(x, y) }
-        } else {
+        }
+              _ => {
             x / y
         }
     }
diff --git a/library/compiler-builtins/libm/src/math/support/modular.rs b/library/compiler-builtins/libm/src/math/support/modular.rs
index cc0edf2f2bc04..026c599c1bba4 100644
--- a/library/compiler-builtins/libm/src/math/support/modular.rs
+++ b/library/compiler-builtins/libm/src/math/support/modular.rs
@@ -231,6 +231,7 @@ mod test {
     use crate::support::modular::Reducer;
 
     #[test]
+    #[cfg_attr(miri, ignore)] // This test is very slow when using Miri
     fn reducer_ops() {
         for n in 33..=63_u8 {
             for x in 0..2 * n {
@@ -259,6 +260,7 @@ mod test {
         }
     }
     #[test]
+    #[cfg_attr(miri, ignore)] // This test is very slow when using Miri
     fn reduction_u8() {
         for y in 1..64u8 {
             for x in 0..2 * y {
diff --git a/library/compiler-builtins/rust-version b/library/compiler-builtins/rust-version
index e3a2981071adc..2f175e966812d 100644
--- a/library/compiler-builtins/rust-version
+++ b/library/compiler-builtins/rust-version
@@ -1 +1 @@
-68ffae46b581747074413e4242ab0c6ecc4db4a9
+2c39ff499469be916d4e45506d1afed69bbaddb7