diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index ceda348025e36..7eb41fec36aba 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -43,7 +43,7 @@ jobs:
           - name: mingw-check
             os: ubuntu-20.04-xl
             env: {}
-          - name: x86_64-gnu-llvm-12
+          - name: x86_64-gnu-llvm-13
             os: ubuntu-20.04-xl
             env: {}
           - name: x86_64-gnu-tools
@@ -274,11 +274,11 @@ jobs:
           - name: x86_64-gnu-distcheck
             os: ubuntu-20.04-xl
             env: {}
-          - name: x86_64-gnu-llvm-12
+          - name: x86_64-gnu-llvm-13
             env:
               RUST_BACKTRACE: 1
             os: ubuntu-20.04-xl
-          - name: x86_64-gnu-llvm-12-stage1
+          - name: x86_64-gnu-llvm-13-stage1
             env:
               RUST_BACKTRACE: 1
             os: ubuntu-20.04-xl
diff --git a/compiler/rustc_ast_lowering/src/lib.rs b/compiler/rustc_ast_lowering/src/lib.rs
index 8dc82e2deeec7..488bd05fd6b89 100644
--- a/compiler/rustc_ast_lowering/src/lib.rs
+++ b/compiler/rustc_ast_lowering/src/lib.rs
@@ -48,7 +48,7 @@ use rustc_data_structures::fx::FxHashMap;
 use rustc_data_structures::sorted_map::SortedMap;
 use rustc_data_structures::stable_hasher::{HashStable, StableHasher};
 use rustc_data_structures::sync::Lrc;
-use rustc_errors::{struct_span_err, Applicability, Handler};
+use rustc_errors::{struct_span_err, Applicability, Handler, StashKey};
 use rustc_hir as hir;
 use rustc_hir::def::{DefKind, LifetimeRes, Namespace, PartialRes, PerNS, Res};
 use rustc_hir::def_id::{LocalDefId, CRATE_DEF_ID};
@@ -2233,7 +2233,7 @@ impl<'a, 'hir> LoweringContext<'a, 'hir> {
                         c.value.span,
                         "using `_` for array lengths is unstable",
                     )
-                    .emit();
+                    .stash(c.value.span, StashKey::UnderscoreForArrayLengths);
                     hir::ArrayLen::Body(self.lower_anon_const(c))
                 }
             }
diff --git a/compiler/rustc_codegen_llvm/src/asm.rs b/compiler/rustc_codegen_llvm/src/asm.rs
index a53946995ee1c..2a6612eb86f12 100644
--- a/compiler/rustc_codegen_llvm/src/asm.rs
+++ b/compiler/rustc_codegen_llvm/src/asm.rs
@@ -3,7 +3,6 @@ use crate::builder::Builder;
 use crate::common::Funclet;
 use crate::context::CodegenCx;
 use crate::llvm;
-use crate::llvm_util;
 use crate::type_::Type;
 use crate::type_of::LayoutLlvmExt;
 use crate::value::Value;
@@ -419,13 +418,6 @@ pub(crate) fn inline_asm_call<'ll>(
         let constraints_ok = llvm::LLVMRustInlineAsmVerify(fty, cons.as_ptr().cast(), cons.len());
         debug!("constraint verification result: {:?}", constraints_ok);
         if constraints_ok {
-            if unwind && llvm_util::get_version() < (13, 0, 0) {
-                bx.cx.sess().span_fatal(
-                    line_spans[0],
-                    "unwinding from inline assembly is only supported on llvm >= 13.",
-                );
-            }
-
             let v = llvm::LLVMRustInlineAsm(
                 fty,
                 asm.as_ptr().cast(),
diff --git a/compiler/rustc_codegen_llvm/src/back/write.rs b/compiler/rustc_codegen_llvm/src/back/write.rs
index 534d32e8a90e9..740a68d0772c1 100644
--- a/compiler/rustc_codegen_llvm/src/back/write.rs
+++ b/compiler/rustc_codegen_llvm/src/back/write.rs
@@ -5,7 +5,7 @@ use crate::back::profiling::{
 use crate::base;
 use crate::common;
 use crate::consts;
-use crate::llvm::{self, DiagnosticInfo, PassManager, SMDiagnostic};
+use crate::llvm::{self, DiagnosticInfo, PassManager};
 use crate::llvm_util;
 use crate::type_::Type;
 use crate::LlvmCodegenBackend;
@@ -304,7 +304,6 @@ impl<'a> DiagnosticHandlers<'a> {
                 remark_passes.as_ptr(),
                 remark_passes.len(),
             );
-            llvm::LLVMRustSetInlineAsmDiagnosticHandler(llcx, inline_asm_handler, data.cast());
             DiagnosticHandlers { data, llcx, old_handler }
         }
     }
@@ -312,9 +311,7 @@ impl<'a> DiagnosticHandlers<'a> {
 
 impl<'a> Drop for DiagnosticHandlers<'a> {
     fn drop(&mut self) {
-        use std::ptr::null_mut;
         unsafe {
-            llvm::LLVMRustSetInlineAsmDiagnosticHandler(self.llcx, inline_asm_handler, null_mut());
             llvm::LLVMRustContextSetDiagnosticHandler(self.llcx, self.old_handler);
             drop(Box::from_raw(self.data));
         }
@@ -342,16 +339,6 @@ fn report_inline_asm(
     cgcx.diag_emitter.inline_asm_error(cookie as u32, msg, level, source);
 }
 
-unsafe extern "C" fn inline_asm_handler(diag: &SMDiagnostic, user: *const c_void, cookie: c_uint) {
-    if user.is_null() {
-        return;
-    }
-    let (cgcx, _) = *(user as *const (&CodegenContext<LlvmCodegenBackend>, &Handler));
-
-    let smdiag = llvm::diagnostic::SrcMgrDiagnostic::unpack(diag);
-    report_inline_asm(cgcx, smdiag.message, smdiag.level, cookie, smdiag.source);
-}
-
 unsafe extern "C" fn diagnostic_handler(info: &DiagnosticInfo, user: *mut c_void) {
     if user.is_null() {
         return;
@@ -423,6 +410,14 @@ fn get_pgo_sample_use_path(config: &ModuleConfig) -> Option<CString> {
         .map(|path_buf| CString::new(path_buf.to_string_lossy().as_bytes()).unwrap())
 }
 
+fn get_instr_profile_output_path(config: &ModuleConfig) -> Option<CString> {
+    if config.instrument_coverage {
+        Some(CString::new("default_%m_%p.profraw").unwrap())
+    } else {
+        None
+    }
+}
+
 pub(crate) unsafe fn optimize_with_new_llvm_pass_manager(
     cgcx: &CodegenContext<LlvmCodegenBackend>,
     diag_handler: &Handler,
@@ -438,6 +433,7 @@ pub(crate) unsafe fn optimize_with_new_llvm_pass_manager(
     let pgo_use_path = get_pgo_use_path(config);
     let pgo_sample_use_path = get_pgo_sample_use_path(config);
     let is_lto = opt_stage == llvm::OptStage::ThinLTO || opt_stage == llvm::OptStage::FatLTO;
+    let instr_profile_output_path = get_instr_profile_output_path(config);
     // Sanitizer instrumentation is only inserted during the pre-link optimization stage.
     let sanitizer_options = if !is_lto {
         Some(llvm::SanitizerOptions {
@@ -488,6 +484,7 @@ pub(crate) unsafe fn optimize_with_new_llvm_pass_manager(
         pgo_gen_path.as_ref().map_or(std::ptr::null(), |s| s.as_ptr()),
         pgo_use_path.as_ref().map_or(std::ptr::null(), |s| s.as_ptr()),
         config.instrument_coverage,
+        instr_profile_output_path.as_ref().map_or(std::ptr::null(), |s| s.as_ptr()),
         config.instrument_gcov,
         pgo_sample_use_path.as_ref().map_or(std::ptr::null(), |s| s.as_ptr()),
         config.debug_info_for_profiling,
diff --git a/compiler/rustc_codegen_llvm/src/builder.rs b/compiler/rustc_codegen_llvm/src/builder.rs
index d3096c73a8a9d..073feecb1647f 100644
--- a/compiler/rustc_codegen_llvm/src/builder.rs
+++ b/compiler/rustc_codegen_llvm/src/builder.rs
@@ -3,7 +3,6 @@ use crate::common::Funclet;
 use crate::context::CodegenCx;
 use crate::llvm::{self, BasicBlock, False};
 use crate::llvm::{AtomicOrdering, AtomicRmwBinOp, SynchronizationScope};
-use crate::llvm_util;
 use crate::type_::Type;
 use crate::type_of::LayoutLlvmExt;
 use crate::value::Value;
@@ -1038,25 +1037,11 @@ impl<'a, 'll, 'tcx> BuilderMethods<'a, 'tcx> for Builder<'a, 'll, 'tcx> {
         dst: &'ll Value,
         cmp: &'ll Value,
         src: &'ll Value,
-        mut order: rustc_codegen_ssa::common::AtomicOrdering,
+        order: rustc_codegen_ssa::common::AtomicOrdering,
         failure_order: rustc_codegen_ssa::common::AtomicOrdering,
         weak: bool,
     ) -> &'ll Value {
         let weak = if weak { llvm::True } else { llvm::False };
-        if llvm_util::get_version() < (13, 0, 0) {
-            use rustc_codegen_ssa::common::AtomicOrdering::*;
-            // Older llvm has the pre-C++17 restriction on
-            // success and failure memory ordering,
-            // requiring the former to be at least as strong as the latter.
-            // So, for llvm 12, we upgrade the success ordering to a stronger
-            // one if necessary.
-            match (order, failure_order) {
-                (Relaxed, Acquire) => order = Acquire,
-                (Release, Acquire) => order = AcquireRelease,
-                (_, SequentiallyConsistent) => order = SequentiallyConsistent,
-                _ => {}
-            }
-        }
         unsafe {
             llvm::LLVMRustBuildAtomicCmpXchg(
                 self.llbuilder,
@@ -1444,51 +1429,37 @@ impl<'a, 'll, 'tcx> Builder<'a, 'll, 'tcx> {
         }
     }
 
-    fn fptoint_sat_broken_in_llvm(&self) -> bool {
-        match self.tcx.sess.target.arch.as_ref() {
-            // FIXME - https://bugs.llvm.org/show_bug.cgi?id=50083
-            "riscv64" => llvm_util::get_version() < (13, 0, 0),
-            _ => false,
-        }
-    }
-
     fn fptoint_sat(
         &mut self,
         signed: bool,
         val: &'ll Value,
         dest_ty: &'ll Type,
     ) -> Option<&'ll Value> {
-        if !self.fptoint_sat_broken_in_llvm() {
-            let src_ty = self.cx.val_ty(val);
-            let (float_ty, int_ty, vector_length) = if self.cx.type_kind(src_ty) == TypeKind::Vector
-            {
-                assert_eq!(self.cx.vector_length(src_ty), self.cx.vector_length(dest_ty));
-                (
-                    self.cx.element_type(src_ty),
-                    self.cx.element_type(dest_ty),
-                    Some(self.cx.vector_length(src_ty)),
-                )
-            } else {
-                (src_ty, dest_ty, None)
-            };
-            let float_width = self.cx.float_width(float_ty);
-            let int_width = self.cx.int_width(int_ty);
-
-            let instr = if signed { "fptosi" } else { "fptoui" };
-            let name = if let Some(vector_length) = vector_length {
-                format!(
-                    "llvm.{}.sat.v{}i{}.v{}f{}",
-                    instr, vector_length, int_width, vector_length, float_width
-                )
-            } else {
-                format!("llvm.{}.sat.i{}.f{}", instr, int_width, float_width)
-            };
-            let f =
-                self.declare_cfn(&name, llvm::UnnamedAddr::No, self.type_func(&[src_ty], dest_ty));
-            Some(self.call(self.type_func(&[src_ty], dest_ty), f, &[val], None))
+        let src_ty = self.cx.val_ty(val);
+        let (float_ty, int_ty, vector_length) = if self.cx.type_kind(src_ty) == TypeKind::Vector {
+            assert_eq!(self.cx.vector_length(src_ty), self.cx.vector_length(dest_ty));
+            (
+                self.cx.element_type(src_ty),
+                self.cx.element_type(dest_ty),
+                Some(self.cx.vector_length(src_ty)),
+            )
         } else {
-            None
-        }
+            (src_ty, dest_ty, None)
+        };
+        let float_width = self.cx.float_width(float_ty);
+        let int_width = self.cx.int_width(int_ty);
+
+        let instr = if signed { "fptosi" } else { "fptoui" };
+        let name = if let Some(vector_length) = vector_length {
+            format!(
+                "llvm.{}.sat.v{}i{}.v{}f{}",
+                instr, vector_length, int_width, vector_length, float_width
+            )
+        } else {
+            format!("llvm.{}.sat.i{}.f{}", instr, int_width, float_width)
+        };
+        let f = self.declare_cfn(&name, llvm::UnnamedAddr::No, self.type_func(&[src_ty], dest_ty));
+        Some(self.call(self.type_func(&[src_ty], dest_ty), f, &[val], None))
     }
 
     pub(crate) fn landing_pad(
diff --git a/compiler/rustc_codegen_llvm/src/context.rs b/compiler/rustc_codegen_llvm/src/context.rs
index 5857b83f6c971..d4d8414723906 100644
--- a/compiler/rustc_codegen_llvm/src/context.rs
+++ b/compiler/rustc_codegen_llvm/src/context.rs
@@ -142,17 +142,6 @@ pub unsafe fn create_module<'ll>(
 
     let mut target_data_layout = sess.target.data_layout.to_string();
     let llvm_version = llvm_util::get_version();
-    if llvm_version < (13, 0, 0) {
-        if sess.target.arch == "powerpc64" {
-            target_data_layout = target_data_layout.replace("-S128", "");
-        }
-        if sess.target.arch == "wasm32" {
-            target_data_layout = "e-m:e-p:32:32-i64:64-n32:64-S128".to_string();
-        }
-        if sess.target.arch == "wasm64" {
-            target_data_layout = "e-m:e-p:64:64-i64:64-n32:64-S128".to_string();
-        }
-    }
     if llvm_version < (14, 0, 0) {
         if sess.target.llvm_target == "i686-pc-windows-msvc"
             || sess.target.llvm_target == "i586-pc-windows-msvc"
diff --git a/compiler/rustc_codegen_llvm/src/llvm/ffi.rs b/compiler/rustc_codegen_llvm/src/llvm/ffi.rs
index 89611fc0dee1b..4ca3dd78caede 100644
--- a/compiler/rustc_codegen_llvm/src/llvm/ffi.rs
+++ b/compiler/rustc_codegen_llvm/src/llvm/ffi.rs
@@ -2360,6 +2360,7 @@ extern "C" {
         PGOGenPath: *const c_char,
         PGOUsePath: *const c_char,
         InstrumentCoverage: bool,
+        InstrProfileOutput: *const c_char,
         InstrumentGCOV: bool,
         PGOSampleUsePath: *const c_char,
         DebugInfoForProfiling: bool,
@@ -2423,12 +2424,6 @@ extern "C" {
         cookie_out: &mut c_uint,
     ) -> &'a SMDiagnostic;
 
-    pub fn LLVMRustSetInlineAsmDiagnosticHandler(
-        C: &Context,
-        H: InlineAsmDiagHandlerTy,
-        CX: *mut c_void,
-    );
-
     #[allow(improper_ctypes)]
     pub fn LLVMRustUnpackSMDiagnostic(
         d: &SMDiagnostic,
diff --git a/compiler/rustc_codegen_llvm/src/llvm_util.rs b/compiler/rustc_codegen_llvm/src/llvm_util.rs
index 96d238eda59d0..f5d676c44e342 100644
--- a/compiler/rustc_codegen_llvm/src/llvm_util.rs
+++ b/compiler/rustc_codegen_llvm/src/llvm_util.rs
@@ -92,16 +92,6 @@ unsafe fn configure_llvm(sess: &Session) {
             add("-generate-arange-section", false);
         }
 
-        // Disable the machine outliner by default in LLVM versions 11 and LLVM
-        // version 12, where it leads to miscompilation.
-        //
-        // Ref:
-        // - https://github.com/rust-lang/rust/issues/85351
-        // - https://reviews.llvm.org/D103167
-        if llvm_util::get_version() < (13, 0, 0) {
-            add("-enable-machine-outliner=never", false);
-        }
-
         match sess.opts.unstable_opts.merge_functions.unwrap_or(sess.target.merge_functions) {
             MergeFunctions::Disabled | MergeFunctions::Trampolines => {}
             MergeFunctions::Aliases => {
diff --git a/compiler/rustc_const_eval/src/interpret/machine.rs b/compiler/rustc_const_eval/src/interpret/machine.rs
index 9b9919fcc2a3d..dedbcf43755cb 100644
--- a/compiler/rustc_const_eval/src/interpret/machine.rs
+++ b/compiler/rustc_const_eval/src/interpret/machine.rs
@@ -343,7 +343,7 @@ pub trait Machine<'mir, 'tcx>: Sized {
     /// operations take `&self`. Use a `RefCell` in `AllocExtra` if you
     /// need to mutate.
     #[inline(always)]
-    fn memory_read(
+    fn before_memory_read(
         _tcx: TyCtxt<'tcx>,
         _machine: &Self,
         _alloc_extra: &Self::AllocExtra,
@@ -355,7 +355,7 @@ pub trait Machine<'mir, 'tcx>: Sized {
 
     /// Hook for performing extra checks on a memory write access.
     #[inline(always)]
-    fn memory_written(
+    fn before_memory_write(
         _tcx: TyCtxt<'tcx>,
         _machine: &mut Self,
         _alloc_extra: &mut Self::AllocExtra,
@@ -367,7 +367,7 @@ pub trait Machine<'mir, 'tcx>: Sized {
 
     /// Hook for performing extra operations on a memory deallocation.
     #[inline(always)]
-    fn memory_deallocated(
+    fn before_memory_deallocation(
         _tcx: TyCtxt<'tcx>,
         _machine: &mut Self,
         _alloc_extra: &mut Self::AllocExtra,
diff --git a/compiler/rustc_const_eval/src/interpret/memory.rs b/compiler/rustc_const_eval/src/interpret/memory.rs
index 75528d6140ce5..98e0c8cd78ea4 100644
--- a/compiler/rustc_const_eval/src/interpret/memory.rs
+++ b/compiler/rustc_const_eval/src/interpret/memory.rs
@@ -327,7 +327,7 @@ impl<'mir, 'tcx: 'mir, M: Machine<'mir, 'tcx>> InterpCx<'mir, 'tcx, M> {
 
         // Let the machine take some extra action
         let size = alloc.size();
-        M::memory_deallocated(
+        M::before_memory_deallocation(
             *self.tcx,
             &mut self.machine,
             &mut alloc.extra,
@@ -575,7 +575,7 @@ impl<'mir, 'tcx: 'mir, M: Machine<'mir, 'tcx>> InterpCx<'mir, 'tcx, M> {
         )?;
         if let Some((alloc_id, offset, prov, alloc)) = ptr_and_alloc {
             let range = alloc_range(offset, size);
-            M::memory_read(*self.tcx, &self.machine, &alloc.extra, (alloc_id, prov), range)?;
+            M::before_memory_read(*self.tcx, &self.machine, &alloc.extra, (alloc_id, prov), range)?;
             Ok(Some(AllocRef { alloc, range, tcx: *self.tcx, alloc_id }))
         } else {
             // Even in this branch we have to be sure that we actually access the allocation, in
@@ -641,7 +641,7 @@ impl<'mir, 'tcx: 'mir, M: Machine<'mir, 'tcx>> InterpCx<'mir, 'tcx, M> {
             // We cannot call `get_raw_mut` inside `check_and_deref_ptr` as that would duplicate `&mut self`.
             let (alloc, machine) = self.get_alloc_raw_mut(alloc_id)?;
             let range = alloc_range(offset, size);
-            M::memory_written(tcx, machine, &mut alloc.extra, (alloc_id, prov), range)?;
+            M::before_memory_write(tcx, machine, &mut alloc.extra, (alloc_id, prov), range)?;
             Ok(Some(AllocRefMut { alloc, range, tcx, alloc_id }))
         } else {
             Ok(None)
@@ -1078,7 +1078,13 @@ impl<'mir, 'tcx: 'mir, M: Machine<'mir, 'tcx>> InterpCx<'mir, 'tcx, M> {
         };
         let src_alloc = self.get_alloc_raw(src_alloc_id)?;
         let src_range = alloc_range(src_offset, size);
-        M::memory_read(*tcx, &self.machine, &src_alloc.extra, (src_alloc_id, src_prov), src_range)?;
+        M::before_memory_read(
+            *tcx,
+            &self.machine,
+            &src_alloc.extra,
+            (src_alloc_id, src_prov),
+            src_range,
+        )?;
         // We need the `dest` ptr for the next operation, so we get it now.
         // We already did the source checks and called the hooks so we are good to return early.
         let Some((dest_alloc_id, dest_offset, dest_prov)) = dest_parts else {
@@ -1103,7 +1109,7 @@ impl<'mir, 'tcx: 'mir, M: Machine<'mir, 'tcx>> InterpCx<'mir, 'tcx, M> {
         // Destination alloc preparations and access hooks.
         let (dest_alloc, extra) = self.get_alloc_raw_mut(dest_alloc_id)?;
         let dest_range = alloc_range(dest_offset, size * num_copies);
-        M::memory_written(
+        M::before_memory_write(
             *tcx,
             extra,
             &mut dest_alloc.extra,
diff --git a/compiler/rustc_errors/src/lib.rs b/compiler/rustc_errors/src/lib.rs
index d2eb4f212eb88..395bf5aad01b6 100644
--- a/compiler/rustc_errors/src/lib.rs
+++ b/compiler/rustc_errors/src/lib.rs
@@ -457,6 +457,7 @@ struct HandlerInner {
 #[derive(Copy, Clone, PartialEq, Eq, PartialOrd, Ord, Hash, Debug)]
 pub enum StashKey {
     ItemNoType,
+    UnderscoreForArrayLengths,
 }
 
 fn default_track_diagnostic(_: &Diagnostic) {}
diff --git a/compiler/rustc_feature/src/builtin_attrs.rs b/compiler/rustc_feature/src/builtin_attrs.rs
index ee46a364546a9..7d3bedbfe4319 100644
--- a/compiler/rustc_feature/src/builtin_attrs.rs
+++ b/compiler/rustc_feature/src/builtin_attrs.rs
@@ -277,7 +277,7 @@ pub const BUILTIN_ATTRIBUTES: &[BuiltinAttribute] = &[
     ungated!(ignore, Normal, template!(Word, NameValueStr: "reason"), WarnFollowing),
     ungated!(
         should_panic, Normal,
-        template!(Word, List: r#"expected = "reason"#, NameValueStr: "reason"), FutureWarnFollowing,
+        template!(Word, List: r#"expected = "reason""#, NameValueStr: "reason"), FutureWarnFollowing,
     ),
     // FIXME(Centril): This can be used on stable but shouldn't.
     ungated!(reexport_test_harness_main, CrateLevel, template!(NameValueStr: "name"), ErrorFollowing),
diff --git a/compiler/rustc_llvm/llvm-wrapper/CoverageMappingWrapper.cpp b/compiler/rustc_llvm/llvm-wrapper/CoverageMappingWrapper.cpp
index 154f554d607df..7da6ab71309dd 100644
--- a/compiler/rustc_llvm/llvm-wrapper/CoverageMappingWrapper.cpp
+++ b/compiler/rustc_llvm/llvm-wrapper/CoverageMappingWrapper.cpp
@@ -24,17 +24,10 @@ extern "C" void LLVMRustCoverageWriteFilenamesSectionToBuffer(
     const char* const Filenames[],
     size_t FilenamesLen,
     RustStringRef BufferOut) {
-#if LLVM_VERSION_GE(13,0)
   SmallVector<std::string,32> FilenameRefs;
   for (size_t i = 0; i < FilenamesLen; i++) {
     FilenameRefs.push_back(std::string(Filenames[i]));
   }
-#else
-  SmallVector<StringRef,32> FilenameRefs;
-  for (size_t i = 0; i < FilenamesLen; i++) {
-    FilenameRefs.push_back(StringRef(Filenames[i]));
-  }
-#endif
   auto FilenamesWriter = coverage::CoverageFilenamesSectionWriter(
     makeArrayRef(FilenameRefs));
   RawRustStringOstream OS(BufferOut);
@@ -109,9 +102,5 @@ extern "C" void LLVMRustCoverageWriteMappingVarNameToString(RustStringRef Str) {
 }
 
 extern "C" uint32_t LLVMRustCoverageMappingVersion() {
-#if LLVM_VERSION_GE(13, 0)
   return coverage::CovMapVersion::Version6;
-#else
-  return coverage::CovMapVersion::Version5;
-#endif
 }
diff --git a/compiler/rustc_llvm/llvm-wrapper/PassWrapper.cpp b/compiler/rustc_llvm/llvm-wrapper/PassWrapper.cpp
index 0a6bd49992d99..b4314223722fc 100644
--- a/compiler/rustc_llvm/llvm-wrapper/PassWrapper.cpp
+++ b/compiler/rustc_llvm/llvm-wrapper/PassWrapper.cpp
@@ -822,7 +822,8 @@ LLVMRustOptimizeWithNewPassManager(
     bool DisableSimplifyLibCalls, bool EmitLifetimeMarkers,
     LLVMRustSanitizerOptions *SanitizerOptions,
     const char *PGOGenPath, const char *PGOUsePath,
-    bool InstrumentCoverage, bool InstrumentGCOV,
+    bool InstrumentCoverage, const char *InstrProfileOutput,
+    bool InstrumentGCOV,
     const char *PGOSampleUsePath, bool DebugInfoForProfiling,
     void* LlvmSelfProfiler,
     LLVMRustSelfProfileBeforePassCallback BeforePassCallback,
@@ -869,19 +870,11 @@ LLVMRustOptimizeWithNewPassManager(
                         PGOOptions::NoCSAction, DebugInfoForProfiling);
   }
 
-#if LLVM_VERSION_GE(13, 0)
   PassBuilder PB(TM, PTO, PGOOpt, &PIC);
   LoopAnalysisManager LAM;
   FunctionAnalysisManager FAM;
   CGSCCAnalysisManager CGAM;
   ModuleAnalysisManager MAM;
-#else
-  PassBuilder PB(DebugPassManager, TM, PTO, PGOOpt, &PIC);
-  LoopAnalysisManager LAM(DebugPassManager);
-  FunctionAnalysisManager FAM(DebugPassManager);
-  CGSCCAnalysisManager CGAM(DebugPassManager);
-  ModuleAnalysisManager MAM(DebugPassManager);
-#endif
 
   FAM.registerPass([&] { return PB.buildDefaultAAPipeline(); });
 
@@ -922,8 +915,11 @@ LLVMRustOptimizeWithNewPassManager(
 
   if (InstrumentCoverage) {
     PipelineStartEPCallbacks.push_back(
-      [](ModulePassManager &MPM, OptimizationLevel Level) {
+      [InstrProfileOutput](ModulePassManager &MPM, OptimizationLevel Level) {
         InstrProfOptions Options;
+        if (InstrProfileOutput) {
+          Options.InstrProfileOutput = InstrProfileOutput;
+        }
         MPM.addPass(InstrProfiling(Options, false));
       }
     );
@@ -1015,11 +1011,7 @@ LLVMRustOptimizeWithNewPassManager(
     }
   }
 
-#if LLVM_VERSION_GE(13, 0)
   ModulePassManager MPM;
-#else
-  ModulePassManager MPM(DebugPassManager);
-#endif
   bool NeedThinLTOBufferPasses = UseThinLTOBuffers;
   if (!NoPrepopulatePasses) {
     // The pre-link pipelines don't support O0 and require using budilO0DefaultPipeline() instead.
@@ -1434,17 +1426,13 @@ LLVMRustCreateThinLTOData(LLVMRustThinLTOModule *modules,
     Ret->ResolvedODR[ModuleIdentifier][GUID] = NewLinkage;
   };
 
-#if LLVM_VERSION_GE(13,0)
   // Uses FromPrevailing visibility scheme which works for many binary
   // formats. We probably could and should use ELF visibility scheme for many of
   // our targets, however.
   lto::Config conf;
   thinLTOResolvePrevailingInIndex(conf, Ret->Index, isPrevailing, recordNewLinkage,
                                   Ret->GUIDPreservedSymbols);
-#else
-  thinLTOResolvePrevailingInIndex(Ret->Index, isPrevailing, recordNewLinkage,
-                                  Ret->GUIDPreservedSymbols);
-#endif
+
   // Here we calculate an `ExportedGUIDs` set for use in the `isExported`
   // callback below. This callback below will dictate the linkage for all
   // summaries in the index, and we basically just only want to ensure that dead
diff --git a/compiler/rustc_llvm/llvm-wrapper/RustWrapper.cpp b/compiler/rustc_llvm/llvm-wrapper/RustWrapper.cpp
index f9bffe6d82392..931ce78721cb8 100644
--- a/compiler/rustc_llvm/llvm-wrapper/RustWrapper.cpp
+++ b/compiler/rustc_llvm/llvm-wrapper/RustWrapper.cpp
@@ -413,18 +413,12 @@ LLVMRustBuildAtomicCmpXchg(LLVMBuilderRef B, LLVMValueRef Target,
                            LLVMValueRef Old, LLVMValueRef Source,
                            LLVMAtomicOrdering Order,
                            LLVMAtomicOrdering FailureOrder, LLVMBool Weak) {
-#if LLVM_VERSION_GE(13,0)
   // Rust probably knows the alignment of the target value and should be able to
   // specify something more precise than MaybeAlign here. See also
   // https://reviews.llvm.org/D97224 which may be a useful reference.
   AtomicCmpXchgInst *ACXI = unwrap(B)->CreateAtomicCmpXchg(
       unwrap(Target), unwrap(Old), unwrap(Source), llvm::MaybeAlign(), fromRust(Order),
       fromRust(FailureOrder));
-#else
-  AtomicCmpXchgInst *ACXI = unwrap(B)->CreateAtomicCmpXchg(
-      unwrap(Target), unwrap(Old), unwrap(Source), fromRust(Order),
-      fromRust(FailureOrder));
-#endif
   ACXI->setWeak(Weak);
   return wrap(ACXI);
 }
@@ -472,19 +466,11 @@ LLVMRustInlineAsm(LLVMTypeRef Ty, char *AsmString, size_t AsmStringLen,
                   char *Constraints, size_t ConstraintsLen,
                   LLVMBool HasSideEffects, LLVMBool IsAlignStack,
                   LLVMRustAsmDialect Dialect, LLVMBool CanThrow) {
-#if LLVM_VERSION_GE(13, 0)
   return wrap(InlineAsm::get(unwrap<FunctionType>(Ty),
                              StringRef(AsmString, AsmStringLen),
                              StringRef(Constraints, ConstraintsLen),
                              HasSideEffects, IsAlignStack,
                              fromRust(Dialect), CanThrow));
-#else
-  return wrap(InlineAsm::get(unwrap<FunctionType>(Ty),
-                             StringRef(AsmString, AsmStringLen),
-                             StringRef(Constraints, ConstraintsLen),
-                             HasSideEffects, IsAlignStack,
-                             fromRust(Dialect)));
-#endif
 }
 
 extern "C" bool LLVMRustInlineAsmVerify(LLVMTypeRef Ty, char *Constraints,
@@ -1274,10 +1260,8 @@ static LLVMRustDiagnosticKind toRust(DiagnosticKind Kind) {
     return LLVMRustDiagnosticKind::Linker;
   case DK_Unsupported:
     return LLVMRustDiagnosticKind::Unsupported;
-#if LLVM_VERSION_GE(13, 0)
   case DK_SrcMgr:
     return LLVMRustDiagnosticKind::SrcMgr;
-#endif
   default:
     return (Kind >= DK_FirstRemark && Kind <= DK_LastRemark)
                ? LLVMRustDiagnosticKind::OptimizationRemarkOther
@@ -1351,30 +1335,11 @@ extern "C" LLVMTypeKind LLVMRustGetTypeKind(LLVMTypeRef Ty) {
 
 DEFINE_SIMPLE_CONVERSION_FUNCTIONS(SMDiagnostic, LLVMSMDiagnosticRef)
 
-#if LLVM_VERSION_LT(13, 0)
-using LLVMInlineAsmDiagHandlerTy = LLVMContext::InlineAsmDiagHandlerTy;
-#else
-using LLVMInlineAsmDiagHandlerTy = void*;
-#endif
-
-extern "C" void LLVMRustSetInlineAsmDiagnosticHandler(
-    LLVMContextRef C, LLVMInlineAsmDiagHandlerTy H, void *CX) {
-  // Diagnostic handlers were unified in LLVM change 5de2d189e6ad, so starting
-  // with LLVM 13 this function is gone.
-#if LLVM_VERSION_LT(13, 0)
-  unwrap(C)->setInlineAsmDiagnosticHandler(H, CX);
-#endif
-}
-
 extern "C" LLVMSMDiagnosticRef LLVMRustGetSMDiagnostic(
     LLVMDiagnosticInfoRef DI, unsigned *Cookie) {
-#if LLVM_VERSION_GE(13, 0)
   llvm::DiagnosticInfoSrcMgr *SM = static_cast<llvm::DiagnosticInfoSrcMgr *>(unwrap(DI));
   *Cookie = SM->getLocCookie();
   return wrap(&SM->getSMDiag());
-#else
-  report_fatal_error("Shouldn't get called on older versions");
-#endif
 }
 
 extern "C" bool LLVMRustUnpackSMDiagnostic(LLVMSMDiagnosticRef DRef,
diff --git a/compiler/rustc_typeck/src/check/coercion.rs b/compiler/rustc_typeck/src/check/coercion.rs
index 6c6bbfa22e30c..da575cb1367b8 100644
--- a/compiler/rustc_typeck/src/check/coercion.rs
+++ b/compiler/rustc_typeck/src/check/coercion.rs
@@ -1594,7 +1594,9 @@ impl<'tcx, 'exprs, E: AsCoercionSite> CoerceMany<'tcx, 'exprs, E> {
         let hir::ExprKind::Loop(_, _, _, loop_span) = expr.kind else { return;};
         let mut span: MultiSpan = vec![loop_span].into();
         span.push_span_label(loop_span, "this might have zero elements to iterate on");
-        for ret_expr in ret_exprs {
+        const MAXITER: usize = 3;
+        let iter = ret_exprs.iter().take(MAXITER);
+        for ret_expr in iter {
             span.push_span_label(
                 ret_expr.span,
                 "if the loop doesn't execute, this value would never get returned",
@@ -1604,6 +1606,12 @@ impl<'tcx, 'exprs, E: AsCoercionSite> CoerceMany<'tcx, 'exprs, E> {
             span,
             "the function expects a value to always be returned, but loops might run zero times",
         );
+        if MAXITER < ret_exprs.len() {
+            err.note(&format!(
+                "if the loop doesn't execute, {} other values would never get returned",
+                ret_exprs.len() - MAXITER
+            ));
+        }
         err.help(
             "return a value for the case when the loop has zero elements to iterate on, or \
            consider changing the return type to account for that possibility",
diff --git a/compiler/rustc_typeck/src/check/expr.rs b/compiler/rustc_typeck/src/check/expr.rs
index 6a6c03a8cba83..9c2fdd875164f 100644
--- a/compiler/rustc_typeck/src/check/expr.rs
+++ b/compiler/rustc_typeck/src/check/expr.rs
@@ -28,7 +28,7 @@ use rustc_data_structures::fx::FxHashMap;
 use rustc_data_structures::stack::ensure_sufficient_stack;
 use rustc_errors::{
     pluralize, struct_span_err, Applicability, Diagnostic, DiagnosticBuilder, DiagnosticId,
-    ErrorGuaranteed,
+    ErrorGuaranteed, StashKey,
 };
 use rustc_hir as hir;
 use rustc_hir::def::{CtorKind, DefKind, Res};
@@ -1307,7 +1307,39 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
                 span: expr.span,
             })
         };
-        self.tcx.mk_array(element_ty, args.len() as u64)
+        let array_len = args.len() as u64;
+        self.suggest_array_len(expr, array_len);
+        self.tcx.mk_array(element_ty, array_len)
+    }
+
+    fn suggest_array_len(&self, expr: &'tcx hir::Expr<'tcx>, array_len: u64) {
+        if let Some(parent_hir_id) = self.tcx.hir().find_parent_node(expr.hir_id) {
+            let ty = match self.tcx.hir().find(parent_hir_id) {
+                Some(
+                    hir::Node::Local(hir::Local { ty: Some(ty), .. })
+                    | hir::Node::Item(hir::Item { kind: hir::ItemKind::Const(ty, _), .. }),
+                ) => Some(ty),
+                _ => None,
+            };
+            if let Some(ty) = ty
+                && let hir::TyKind::Array(_, length) = ty.kind
+                && let hir::ArrayLen::Body(hir::AnonConst { hir_id, .. }) = length
+                && let Some(span) = self.tcx.hir().opt_span(hir_id)
+            {
+                match self.tcx.sess.diagnostic().steal_diagnostic(span, StashKey::UnderscoreForArrayLengths) {
+                    Some(mut err) => {
+                        err.span_suggestion(
+                            span,
+                            "consider specifying the array length",
+                            array_len,
+                            Applicability::MaybeIncorrect,
+                        );
+                        err.emit();
+                    }
+                    None => ()
+                }
+            }
+        }
     }
 
     fn check_expr_const_block(
@@ -1333,10 +1365,13 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
         element: &'tcx hir::Expr<'tcx>,
         count: &'tcx hir::ArrayLen,
         expected: Expectation<'tcx>,
-        _expr: &'tcx hir::Expr<'tcx>,
+        expr: &'tcx hir::Expr<'tcx>,
     ) -> Ty<'tcx> {
         let tcx = self.tcx;
         let count = self.array_length_to_const(count);
+        if let Some(count) = count.try_eval_usize(tcx, self.param_env) {
+            self.suggest_array_len(expr, count);
+        }
 
         let uty = match expected {
             ExpectHasType(uty) => match *uty.kind() {
diff --git a/library/core/src/cmp.rs b/library/core/src/cmp.rs
index 20bb67687848f..171f49022369a 100644
--- a/library/core/src/cmp.rs
+++ b/library/core/src/cmp.rs
@@ -1139,11 +1139,7 @@ pub trait PartialOrd<Rhs: ?Sized = Self>: PartialEq<Rhs> {
     #[must_use]
     #[stable(feature = "rust1", since = "1.0.0")]
     fn le(&self, other: &Rhs) -> bool {
-        // Pattern `Some(Less | Eq)` optimizes worse than negating `None | Some(Greater)`.
-        // FIXME: The root cause was fixed upstream in LLVM with:
-        // https://github.com/llvm/llvm-project/commit/9bad7de9a3fb844f1ca2965f35d0c2a3d1e11775
-        // Revert this workaround once support for LLVM 12 gets dropped.
-        !matches!(self.partial_cmp(other), None | Some(Greater))
+        matches!(self.partial_cmp(other), Some(Less | Equal))
     }
 
     /// This method tests greater than (for `self` and `other`) and is used by the `>` operator.
diff --git a/src/bootstrap/native.rs b/src/bootstrap/native.rs
index 8b50d5dc52bc1..1bba5e68be446 100644
--- a/src/bootstrap/native.rs
+++ b/src/bootstrap/native.rs
@@ -515,11 +515,11 @@ fn check_llvm_version(builder: &Builder<'_>, llvm_config: &Path) {
     let version = output(cmd.arg("--version"));
     let mut parts = version.split('.').take(2).filter_map(|s| s.parse::<u32>().ok());
     if let (Some(major), Some(_minor)) = (parts.next(), parts.next()) {
-        if major >= 12 {
+        if major >= 13 {
             return;
         }
     }
-    panic!("\n\nbad LLVM version: {}, need >=12.0\n\n", version)
+    panic!("\n\nbad LLVM version: {}, need >=13.0\n\n", version)
 }
 
 fn configure_cmake(
diff --git a/src/ci/docker/host-x86_64/x86_64-gnu-llvm-12-stage1/Dockerfile b/src/ci/docker/host-x86_64/x86_64-gnu-llvm-13-stage1/Dockerfile
similarity index 89%
rename from src/ci/docker/host-x86_64/x86_64-gnu-llvm-12-stage1/Dockerfile
rename to src/ci/docker/host-x86_64/x86_64-gnu-llvm-13-stage1/Dockerfile
index c2f3a16d273b0..21891c1244d7c 100644
--- a/src/ci/docker/host-x86_64/x86_64-gnu-llvm-12-stage1/Dockerfile
+++ b/src/ci/docker/host-x86_64/x86_64-gnu-llvm-13-stage1/Dockerfile
@@ -1,4 +1,4 @@
-FROM ubuntu:20.04
+FROM ubuntu:22.04
 
 ARG DEBIAN_FRONTEND=noninteractive
 RUN apt-get update && apt-get install -y --no-install-recommends \
@@ -14,8 +14,8 @@ RUN apt-get update && apt-get install -y --no-install-recommends \
     cmake \
     sudo \
     gdb \
-    llvm-12-tools \
-    llvm-12-dev \
+    llvm-13-tools \
+    llvm-13-dev \
     libedit-dev \
     libssl-dev \
     pkg-config \
@@ -29,7 +29,7 @@ RUN sh /scripts/sccache.sh
 # using llvm-link-shared due to libffi issues -- see #34486
 ENV RUST_CONFIGURE_ARGS \
     --build=x86_64-unknown-linux-gnu \
-    --llvm-root=/usr/lib/llvm-12 \
+    --llvm-root=/usr/lib/llvm-13 \
     --enable-llvm-link-shared \
     --set rust.thin-lto-import-instr-limit=10
 
@@ -41,4 +41,4 @@ ENV SCRIPT python2.7 ../x.py --stage 1 test --exclude src/tools/tidy && \
     # It will also detect tests lacking `// EMIT_MIR_FOR_EACH_BIT_WIDTH`,
     # despite having different output on 32-bit vs 64-bit targets.
     python2.7 ../x.py --stage 1 test src/test/mir-opt \
-    --host='' --target=i686-unknown-linux-gnu
\ No newline at end of file
+    --host='' --target=i686-unknown-linux-gnu
diff --git a/src/ci/docker/host-x86_64/x86_64-gnu-llvm-12/Dockerfile b/src/ci/docker/host-x86_64/x86_64-gnu-llvm-13/Dockerfile
similarity index 96%
rename from src/ci/docker/host-x86_64/x86_64-gnu-llvm-12/Dockerfile
rename to src/ci/docker/host-x86_64/x86_64-gnu-llvm-13/Dockerfile
index 14d0ffd75005f..5f3af2f47caec 100644
--- a/src/ci/docker/host-x86_64/x86_64-gnu-llvm-12/Dockerfile
+++ b/src/ci/docker/host-x86_64/x86_64-gnu-llvm-13/Dockerfile
@@ -1,4 +1,4 @@
-FROM ubuntu:20.04
+FROM ubuntu:22.04
 
 ARG DEBIAN_FRONTEND=noninteractive
 
@@ -17,8 +17,8 @@ RUN apt-get update && apt-get install -y --no-install-recommends \
   cmake \
   sudo \
   gdb \
-  llvm-12-tools \
-  llvm-12-dev \
+  llvm-13-tools \
+  llvm-13-dev \
   libedit-dev \
   libssl-dev \
   pkg-config \
@@ -40,7 +40,7 @@ RUN sh /scripts/sccache.sh
 # using llvm-link-shared due to libffi issues -- see #34486
 ENV RUST_CONFIGURE_ARGS \
       --build=x86_64-unknown-linux-gnu \
-      --llvm-root=/usr/lib/llvm-12 \
+      --llvm-root=/usr/lib/llvm-13 \
       --enable-llvm-link-shared \
       --set rust.thin-lto-import-instr-limit=10
 
diff --git a/src/ci/github-actions/ci.yml b/src/ci/github-actions/ci.yml
index a21400cc4726d..91204eb0b0572 100644
--- a/src/ci/github-actions/ci.yml
+++ b/src/ci/github-actions/ci.yml
@@ -284,7 +284,7 @@ jobs:
           - name: mingw-check
             <<: *job-linux-xl
 
-          - name: x86_64-gnu-llvm-12
+          - name: x86_64-gnu-llvm-13
             <<: *job-linux-xl
             
           - name: x86_64-gnu-tools
@@ -431,12 +431,12 @@ jobs:
           - name: x86_64-gnu-distcheck
             <<: *job-linux-xl
 
-          - name: x86_64-gnu-llvm-12
+          - name: x86_64-gnu-llvm-13
             env:
               RUST_BACKTRACE: 1
             <<: *job-linux-xl
 
-          - name: x86_64-gnu-llvm-12-stage1
+          - name: x86_64-gnu-llvm-13-stage1
             env:
               RUST_BACKTRACE: 1
             <<: *job-linux-xl
diff --git a/src/doc/rustc/src/instrument-coverage.md b/src/doc/rustc/src/instrument-coverage.md
index 0ae9e53af3cd2..38fd5c9699763 100644
--- a/src/doc/rustc/src/instrument-coverage.md
+++ b/src/doc/rustc/src/instrument-coverage.md
@@ -97,7 +97,17 @@ $ echo "{some: 'thing'}" | target/debug/examples/formatjson5 -
 }
 ```
 
-After running this program, a new file, `default.profraw`, should be in the current working directory. It's often preferable to set a specific file name or path. You can change the output file using the environment variable `LLVM_PROFILE_FILE`:
+After running this program, a new file named like `default_11699812450447639123_0_20944` should be in the current working directory.
+A new, unique file name will be generated each time the program is run to avoid overwriting previous data.
+
+```shell
+$ echo "{some: 'thing'}" | target/debug/examples/formatjson5 -
+...
+$ ls default_*.profraw
+default_11699812450447639123_0_20944.profraw
+```
+
+You can also set a specific file name or path for the generated `.profraw` files by using the environment variable `LLVM_PROFILE_FILE`:
 
 ```shell
 $ echo "{some: 'thing'}" \
@@ -115,6 +125,9 @@ If `LLVM_PROFILE_FILE` contains a path to a non-existent directory, the missing
 -   `%Nm` - the instrumented binary’s signature: The runtime creates a pool of N raw profiles, used for on-line profile merging. The runtime takes care of selecting a raw profile from the pool, locking it, and updating it before the program exits. `N` must be between `1` and `9`, and defaults to `1` if omitted (with simply `%m`).
 -   `%c` - Does not add anything to the filename, but enables a mode (on some platforms, including Darwin) in which profile counter updates are continuously synced to a file. This means that if the instrumented program crashes, or is killed by a signal, perfect coverage information can still be recovered.
 
+In the first example above, the value `11699812450447639123_0` in the generated filename is the instrumented binary's signature,
+which replaced the `%m` pattern and the value `20944` is the process ID of the binary being executed.
+
 ## Installing LLVM coverage tools
 
 LLVM's supplies two tools—`llvm-profdata` and `llvm-cov`—that process coverage data and generate reports. There are several ways to find and/or install these tools, but note that the coverage mapping data generated by the Rust compiler requires LLVM version 12 or higher, and processing the *raw* data may require exactly the LLVM version used by the compiler. (`llvm-cov --version` typically shows the tool's LLVM version number, and `rustc --verbose --version` shows the version of LLVM used by the Rust compiler.)
@@ -181,11 +194,10 @@ A typical use case for coverage analysis is test coverage. Rust's source-based c
 
 The following example (using the [`json5format`] crate, for demonstration purposes) show how to generate and analyze coverage results for all tests in a crate.
 
-Since `cargo test` both builds and runs the tests, we set both the additional `RUSTFLAGS`, to add the `-C instrument-coverage` flag, and `LLVM_PROFILE_FILE`, to set a custom filename for the raw profiling data generated during the test runs. Since there may be more than one test binary, apply `%m` in the filename pattern. This generates unique names for each test binary. (Otherwise, each executed test binary would overwrite the coverage results from the previous binary.)
+Since `cargo test` both builds and runs the tests, we set the additional `RUSTFLAGS`, to add the `-C instrument-coverage` flag.
 
 ```shell
 $ RUSTFLAGS="-C instrument-coverage" \
-    LLVM_PROFILE_FILE="json5format-%m.profraw" \
     cargo test --tests
 ```
 
@@ -210,7 +222,7 @@ test result: ok. 31 passed; 0 failed; 0 ignored; 0 measured; 0 filtered out
 You should have one or more `.profraw` files now, one for each test binary. Run the `profdata` tool to merge them:
 
 ```shell
-$ llvm-profdata merge -sparse json5format-*.profraw -o json5format.profdata
+$ llvm-profdata merge -sparse default_*.profraw -o json5format.profdata
 ```
 
 Then run the `cov` tool, with the `profdata` file and all test binaries:
@@ -230,6 +242,8 @@ $ llvm-cov show \
     --Xdemangler=rustfilt | less -R
 ```
 
+> **Note**: If overriding the default `profraw` file name via the `LLVM_PROFILE_FILE` environment variable, it's highly recommended to use the `%m` and `%p` special pattern strings to generate unique file names in the case of more than a single test binary being executed.
+
 > **Note**: The command line option `--ignore-filename-regex=/.cargo/registry`, which excludes the sources for dependencies from the coverage results.\_
 
 ### Tips for listing the binaries automatically
@@ -271,9 +285,8 @@ To include doc tests in the coverage results, drop the `--tests` flag, and apply
 ```bash
 $ RUSTFLAGS="-C instrument-coverage" \
   RUSTDOCFLAGS="-C instrument-coverage -Z unstable-options --persist-doctests target/debug/doctestbins" \
-  LLVM_PROFILE_FILE="json5format-%m.profraw" \
     cargo test
-$ llvm-profdata merge -sparse json5format-*.profraw -o json5format.profdata
+$ llvm-profdata merge -sparse default_*.profraw -o json5format.profdata
 ```
 
 The `-Z unstable-options --persist-doctests` flag is required, to save the test binaries
@@ -302,8 +315,7 @@ $ llvm-cov report \
 > version without doc tests, include:
 
 -   The `cargo test ... --no-run` command is updated with the same environment variables
-    and flags used to _build_ the tests, _including_ the doc tests. (`LLVM_PROFILE_FILE`
-    is only used when _running_ the tests.)
+    and flags used to _build_ the tests, _including_ the doc tests.
 -   The file glob pattern `target/debug/doctestbins/*/rust_out` adds the `rust_out`
     binaries generated for doc tests (note, however, that some `rust_out` files may not
     be executable binaries).
diff --git a/src/test/assembly/aarch64-pointer-auth.rs b/src/test/assembly/aarch64-pointer-auth.rs
index 27e289086b9dd..da14cd026780a 100644
--- a/src/test/assembly/aarch64-pointer-auth.rs
+++ b/src/test/assembly/aarch64-pointer-auth.rs
@@ -1,6 +1,5 @@
 // Test that PAC instructions are emitted when branch-protection is specified.
 
-// min-llvm-version: 10.0.1
 // assembly-output: emit-asm
 // compile-flags: --target aarch64-unknown-linux-gnu
 // compile-flags: -Z branch-protection=pac-ret,leaf
diff --git a/src/test/assembly/asm/avr-modifiers.rs b/src/test/assembly/asm/avr-modifiers.rs
index aba4c982c7305..ffdc8f2e351dd 100644
--- a/src/test/assembly/asm/avr-modifiers.rs
+++ b/src/test/assembly/asm/avr-modifiers.rs
@@ -1,4 +1,3 @@
-// min-llvm-version: 13.0
 // assembly-output: emit-asm
 // compile-flags: --target avr-unknown-gnu-atmega328
 // needs-llvm-components: avr
diff --git a/src/test/assembly/asm/avr-types.rs b/src/test/assembly/asm/avr-types.rs
index 53a601e51c8bf..58bf1ad9e35eb 100644
--- a/src/test/assembly/asm/avr-types.rs
+++ b/src/test/assembly/asm/avr-types.rs
@@ -1,4 +1,3 @@
-// min-llvm-version: 13.0
 // assembly-output: emit-asm
 // compile-flags: --target avr-unknown-gnu-atmega328
 // needs-llvm-components: avr
diff --git a/src/test/assembly/asm/bpf-types.rs b/src/test/assembly/asm/bpf-types.rs
index 3428d93fb1205..f894644cc20ee 100644
--- a/src/test/assembly/asm/bpf-types.rs
+++ b/src/test/assembly/asm/bpf-types.rs
@@ -1,4 +1,3 @@
-// min-llvm-version: 13.0
 // assembly-output: emit-asm
 // compile-flags: --target bpfel-unknown-none -C target_feature=+alu32
 // needs-llvm-components: bpf
diff --git a/src/test/assembly/asm/msp430-types.rs b/src/test/assembly/asm/msp430-types.rs
index 6cfb86e276e23..4fa2e8081f816 100644
--- a/src/test/assembly/asm/msp430-types.rs
+++ b/src/test/assembly/asm/msp430-types.rs
@@ -1,4 +1,3 @@
-// min-llvm-version: 13.0
 // assembly-output: emit-asm
 // compile-flags: --target msp430-none-elf
 // needs-llvm-components: msp430
diff --git a/src/test/assembly/asm/powerpc-types.rs b/src/test/assembly/asm/powerpc-types.rs
index b8859c07e164f..0ca8908497ad7 100644
--- a/src/test/assembly/asm/powerpc-types.rs
+++ b/src/test/assembly/asm/powerpc-types.rs
@@ -1,4 +1,3 @@
-// min-llvm-version: 12.0.1
 // revisions: powerpc powerpc64
 // assembly-output: emit-asm
 //[powerpc] compile-flags: --target powerpc-unknown-linux-gnu
diff --git a/src/test/assembly/stack-protector/stack-protector-target-support.rs b/src/test/assembly/stack-protector/stack-protector-target-support.rs
index 5ba46d082e157..2fb62e93ea36c 100644
--- a/src/test/assembly/stack-protector/stack-protector-target-support.rs
+++ b/src/test/assembly/stack-protector/stack-protector-target-support.rs
@@ -156,7 +156,6 @@
 // [r74] needs-llvm-components: x86
 // [r75] compile-flags:--target x86_64-fortanix-unknown-sgx
 // [r75] needs-llvm-components: x86
-// [r75] min-llvm-version: 11.0.0
 // [r76] compile-flags:--target x86_64-fuchsia
 // [r76] needs-llvm-components: x86
 // [r77] compile-flags:--target x86_64-linux-android
diff --git a/src/test/codegen/asm-may_unwind.rs b/src/test/codegen/asm-may_unwind.rs
index bf4202764a7ec..c97933035d101 100644
--- a/src/test/codegen/asm-may_unwind.rs
+++ b/src/test/codegen/asm-may_unwind.rs
@@ -1,4 +1,3 @@
-// min-llvm-version: 13.0.0
 // compile-flags: -O
 // only-x86_64
 
diff --git a/src/test/codegen/atomic-operations-llvm-12.rs b/src/test/codegen/atomic-operations-llvm-12.rs
deleted file mode 100644
index bd4c63dcff1d7..0000000000000
--- a/src/test/codegen/atomic-operations-llvm-12.rs
+++ /dev/null
@@ -1,84 +0,0 @@
-// Code generation of atomic operations for LLVM 12
-// ignore-llvm-version: 13 - 99
-// compile-flags: -O
-#![crate_type = "lib"]
-
-use std::sync::atomic::{AtomicI32, Ordering::*};
-
-// CHECK-LABEL: @compare_exchange
-#[no_mangle]
-pub fn compare_exchange(a: &AtomicI32) {
-    // CHECK: cmpxchg i32* %{{.*}}, i32 0, i32 10 monotonic monotonic
-    // CHECK: cmpxchg i32* %{{.*}}, i32 0, i32 11 acquire acquire
-    // CHECK: cmpxchg i32* %{{.*}}, i32 0, i32 12 seq_cst seq_cst
-    let _ = a.compare_exchange(0, 10, Relaxed, Relaxed);
-    let _ = a.compare_exchange(0, 11, Relaxed, Acquire);
-    let _ = a.compare_exchange(0, 12, Relaxed, SeqCst);
-
-    // CHECK: cmpxchg i32* %{{.*}}, i32 0, i32 20 release monotonic
-    // CHECK: cmpxchg i32* %{{.*}}, i32 0, i32 21 acq_rel acquire
-    // CHECK: cmpxchg i32* %{{.*}}, i32 0, i32 22 seq_cst seq_cst
-    let _ = a.compare_exchange(0, 20, Release, Relaxed);
-    let _ = a.compare_exchange(0, 21, Release, Acquire);
-    let _ = a.compare_exchange(0, 22, Release, SeqCst);
-
-    // CHECK: cmpxchg i32* %{{.*}}, i32 0, i32 30 acquire monotonic
-    // CHECK: cmpxchg i32* %{{.*}}, i32 0, i32 31 acquire acquire
-    // CHECK: cmpxchg i32* %{{.*}}, i32 0, i32 32 seq_cst seq_cst
-    let _ = a.compare_exchange(0, 30, Acquire, Relaxed);
-    let _ = a.compare_exchange(0, 31, Acquire, Acquire);
-    let _ = a.compare_exchange(0, 32, Acquire, SeqCst);
-
-    // CHECK: cmpxchg i32* %{{.*}}, i32 0, i32 40 acq_rel monotonic
-    // CHECK: cmpxchg i32* %{{.*}}, i32 0, i32 41 acq_rel acquire
-    // CHECK: cmpxchg i32* %{{.*}}, i32 0, i32 42 seq_cst seq_cst
-    let _ = a.compare_exchange(0, 40, AcqRel, Relaxed);
-    let _ = a.compare_exchange(0, 41, AcqRel, Acquire);
-    let _ = a.compare_exchange(0, 42, AcqRel, SeqCst);
-
-    // CHECK: cmpxchg i32* %{{.*}}, i32 0, i32 50 seq_cst monotonic
-    // CHECK: cmpxchg i32* %{{.*}}, i32 0, i32 51 seq_cst acquire
-    // CHECK: cmpxchg i32* %{{.*}}, i32 0, i32 52 seq_cst seq_cst
-    let _ = a.compare_exchange(0, 50, SeqCst, Relaxed);
-    let _ = a.compare_exchange(0, 51, SeqCst, Acquire);
-    let _ = a.compare_exchange(0, 52, SeqCst, SeqCst);
-}
-
-// CHECK-LABEL: @compare_exchange_weak
-#[no_mangle]
-pub fn compare_exchange_weak(w: &AtomicI32) {
-    // CHECK: cmpxchg weak i32* %{{.*}}, i32 1, i32 10 monotonic monotonic
-    // CHECK: cmpxchg weak i32* %{{.*}}, i32 1, i32 11 acquire acquire
-    // CHECK: cmpxchg weak i32* %{{.*}}, i32 1, i32 12 seq_cst seq_cst
-    let _ = w.compare_exchange_weak(1, 10, Relaxed, Relaxed);
-    let _ = w.compare_exchange_weak(1, 11, Relaxed, Acquire);
-    let _ = w.compare_exchange_weak(1, 12, Relaxed, SeqCst);
-
-    // CHECK: cmpxchg weak i32* %{{.*}}, i32 1, i32 20 release monotonic
-    // CHECK: cmpxchg weak i32* %{{.*}}, i32 1, i32 21 acq_rel acquire
-    // CHECK: cmpxchg weak i32* %{{.*}}, i32 1, i32 22 seq_cst seq_cst
-    let _ = w.compare_exchange_weak(1, 20, Release, Relaxed);
-    let _ = w.compare_exchange_weak(1, 21, Release, Acquire);
-    let _ = w.compare_exchange_weak(1, 22, Release, SeqCst);
-
-    // CHECK: cmpxchg weak i32* %{{.*}}, i32 1, i32 30 acquire monotonic
-    // CHECK: cmpxchg weak i32* %{{.*}}, i32 1, i32 31 acquire acquire
-    // CHECK: cmpxchg weak i32* %{{.*}}, i32 1, i32 32 seq_cst seq_cst
-    let _ = w.compare_exchange_weak(1, 30, Acquire, Relaxed);
-    let _ = w.compare_exchange_weak(1, 31, Acquire, Acquire);
-    let _ = w.compare_exchange_weak(1, 32, Acquire, SeqCst);
-
-    // CHECK: cmpxchg weak i32* %{{.*}}, i32 1, i32 40 acq_rel monotonic
-    // CHECK: cmpxchg weak i32* %{{.*}}, i32 1, i32 41 acq_rel acquire
-    // CHECK: cmpxchg weak i32* %{{.*}}, i32 1, i32 42 seq_cst seq_cst
-    let _ = w.compare_exchange_weak(1, 40, AcqRel, Relaxed);
-    let _ = w.compare_exchange_weak(1, 41, AcqRel, Acquire);
-    let _ = w.compare_exchange_weak(1, 42, AcqRel, SeqCst);
-
-    // CHECK: cmpxchg weak i32* %{{.*}}, i32 1, i32 50 seq_cst monotonic
-    // CHECK: cmpxchg weak i32* %{{.*}}, i32 1, i32 51 seq_cst acquire
-    // CHECK: cmpxchg weak i32* %{{.*}}, i32 1, i32 52 seq_cst seq_cst
-    let _ = w.compare_exchange_weak(1, 50, SeqCst, Relaxed);
-    let _ = w.compare_exchange_weak(1, 51, SeqCst, Acquire);
-    let _ = w.compare_exchange_weak(1, 52, SeqCst, SeqCst);
-}
diff --git a/src/test/codegen/atomic-operations.rs b/src/test/codegen/atomic-operations.rs
index 771cf58725aaa..d2bc618dfc528 100644
--- a/src/test/codegen/atomic-operations.rs
+++ b/src/test/codegen/atomic-operations.rs
@@ -1,5 +1,4 @@
 // Code generation of atomic operations.
-// min-llvm-version: 13.0
 // compile-flags: -O
 #![crate_type = "lib"]
 
diff --git a/src/test/codegen/branch-protection.rs b/src/test/codegen/branch-protection.rs
index b23073778c0b5..994c71b261982 100644
--- a/src/test/codegen/branch-protection.rs
+++ b/src/test/codegen/branch-protection.rs
@@ -1,7 +1,6 @@
 // Test that the correct module flags are emitted with different branch protection flags.
 
 // revisions: BTI PACRET LEAF BKEY NONE
-// min-llvm-version: 12.0.0
 // needs-llvm-components: aarch64
 // [BTI] compile-flags: -Z branch-protection=bti
 // [PACRET] compile-flags: -Z branch-protection=pac-ret
diff --git a/src/test/codegen/instrument-coverage.rs b/src/test/codegen/instrument-coverage.rs
new file mode 100644
index 0000000000000..78f8875a2d90c
--- /dev/null
+++ b/src/test/codegen/instrument-coverage.rs
@@ -0,0 +1,17 @@
+// Test that `-Cinstrument-coverage` creates expected __llvm_profile_filename symbol in LLVM IR.
+
+// needs-profiler-support
+// compile-flags: -Cinstrument-coverage
+
+// CHECK: @__llvm_profile_filename = {{.*}}"default_%m_%p.profraw\00"{{.*}}
+
+#![crate_type="lib"]
+
+#[inline(never)]
+fn some_function() {
+
+}
+
+pub fn some_other_function() {
+    some_function();
+}
diff --git a/src/test/codegen/merge-functions.rs b/src/test/codegen/merge-functions.rs
index d6caeeee89669..8e8fe5c964d3c 100644
--- a/src/test/codegen/merge-functions.rs
+++ b/src/test/codegen/merge-functions.rs
@@ -1,3 +1,4 @@
+// min-llvm-version: 14.0
 // revisions: O Os
 //[Os] compile-flags: -Copt-level=s
 //[O] compile-flags: -O
diff --git a/src/test/mir-opt/asm_unwind_panic_abort.rs b/src/test/mir-opt/asm_unwind_panic_abort.rs
index 8201d54348a83..ad8f9398e7f3c 100644
--- a/src/test/mir-opt/asm_unwind_panic_abort.rs
+++ b/src/test/mir-opt/asm_unwind_panic_abort.rs
@@ -1,7 +1,6 @@
 //! Tests that unwinding from an asm block is caught and forced to abort
 //! when `-C panic=abort`.
 
-// min-llvm-version: 13.0.0
 // only-x86_64
 // compile-flags: -C panic=abort
 // no-prefer-dynamic
diff --git a/src/test/ui/array-slice-vec/suggest-array-length.fixed b/src/test/ui/array-slice-vec/suggest-array-length.fixed
new file mode 100644
index 0000000000000..bae3ab74af676
--- /dev/null
+++ b/src/test/ui/array-slice-vec/suggest-array-length.fixed
@@ -0,0 +1,14 @@
+// run-rustfix
+#![allow(unused_variables, dead_code, non_upper_case_globals)]
+
+fn main() {
+    const Foo: [i32; 3] = [1, 2, 3];
+    //~^ ERROR in expressions, `_` can only be used on the left-hand side of an assignment
+    //~| ERROR using `_` for array lengths is unstable
+    let foo: [i32; 3] = [1, 2, 3];
+    //~^ ERROR in expressions, `_` can only be used on the left-hand side of an assignment
+    //~| ERROR using `_` for array lengths is unstable
+    let bar: [i32; 3] = [0; 3];
+    //~^ ERROR in expressions, `_` can only be used on the left-hand side of an assignment
+    //~| ERROR using `_` for array lengths is unstable
+}
diff --git a/src/test/ui/array-slice-vec/suggest-array-length.rs b/src/test/ui/array-slice-vec/suggest-array-length.rs
new file mode 100644
index 0000000000000..b0867f4e39676
--- /dev/null
+++ b/src/test/ui/array-slice-vec/suggest-array-length.rs
@@ -0,0 +1,14 @@
+// run-rustfix
+#![allow(unused_variables, dead_code, non_upper_case_globals)]
+
+fn main() {
+    const Foo: [i32; _] = [1, 2, 3];
+    //~^ ERROR in expressions, `_` can only be used on the left-hand side of an assignment
+    //~| ERROR using `_` for array lengths is unstable
+    let foo: [i32; _] = [1, 2, 3];
+    //~^ ERROR in expressions, `_` can only be used on the left-hand side of an assignment
+    //~| ERROR using `_` for array lengths is unstable
+    let bar: [i32; _] = [0; 3];
+    //~^ ERROR in expressions, `_` can only be used on the left-hand side of an assignment
+    //~| ERROR using `_` for array lengths is unstable
+}
diff --git a/src/test/ui/array-slice-vec/suggest-array-length.stderr b/src/test/ui/array-slice-vec/suggest-array-length.stderr
new file mode 100644
index 0000000000000..9000f71602850
--- /dev/null
+++ b/src/test/ui/array-slice-vec/suggest-array-length.stderr
@@ -0,0 +1,48 @@
+error: in expressions, `_` can only be used on the left-hand side of an assignment
+  --> $DIR/suggest-array-length.rs:8:20
+   |
+LL |     let foo: [i32; _] = [1, 2, 3];
+   |                    ^ `_` not allowed here
+
+error: in expressions, `_` can only be used on the left-hand side of an assignment
+  --> $DIR/suggest-array-length.rs:11:20
+   |
+LL |     let bar: [i32; _] = [0; 3];
+   |                    ^ `_` not allowed here
+
+error: in expressions, `_` can only be used on the left-hand side of an assignment
+  --> $DIR/suggest-array-length.rs:5:22
+   |
+LL |     const Foo: [i32; _] = [1, 2, 3];
+   |                      ^ `_` not allowed here
+
+error[E0658]: using `_` for array lengths is unstable
+  --> $DIR/suggest-array-length.rs:5:22
+   |
+LL |     const Foo: [i32; _] = [1, 2, 3];
+   |                      ^ help: consider specifying the array length: `3`
+   |
+   = note: see issue #85077 <https://github.com/rust-lang/rust/issues/85077> for more information
+   = help: add `#![feature(generic_arg_infer)]` to the crate attributes to enable
+
+error[E0658]: using `_` for array lengths is unstable
+  --> $DIR/suggest-array-length.rs:8:20
+   |
+LL |     let foo: [i32; _] = [1, 2, 3];
+   |                    ^ help: consider specifying the array length: `3`
+   |
+   = note: see issue #85077 <https://github.com/rust-lang/rust/issues/85077> for more information
+   = help: add `#![feature(generic_arg_infer)]` to the crate attributes to enable
+
+error[E0658]: using `_` for array lengths is unstable
+  --> $DIR/suggest-array-length.rs:11:20
+   |
+LL |     let bar: [i32; _] = [0; 3];
+   |                    ^ help: consider specifying the array length: `3`
+   |
+   = note: see issue #85077 <https://github.com/rust-lang/rust/issues/85077> for more information
+   = help: add `#![feature(generic_arg_infer)]` to the crate attributes to enable
+
+error: aborting due to 6 previous errors
+
+For more information about this error, try `rustc --explain E0658`.
diff --git a/src/test/ui/asm/aarch64/may_unwind.rs b/src/test/ui/asm/aarch64/may_unwind.rs
index ac8cc62027e4a..dfd891b4212d5 100644
--- a/src/test/ui/asm/aarch64/may_unwind.rs
+++ b/src/test/ui/asm/aarch64/may_unwind.rs
@@ -1,4 +1,3 @@
-// min-llvm-version: 13.0.0
 // only-aarch64
 // run-pass
 // needs-asm-support
diff --git a/src/test/ui/asm/may_unwind.rs b/src/test/ui/asm/may_unwind.rs
index 117c0a63aa4b9..b9479c44bf11d 100644
--- a/src/test/ui/asm/may_unwind.rs
+++ b/src/test/ui/asm/may_unwind.rs
@@ -1,4 +1,3 @@
-// min-llvm-version: 13.0.0
 // run-pass
 // needs-asm-support
 
diff --git a/src/test/ui/asm/x86_64/may_unwind.rs b/src/test/ui/asm/x86_64/may_unwind.rs
index 9844d63f0cd43..badc4fec82248 100644
--- a/src/test/ui/asm/x86_64/may_unwind.rs
+++ b/src/test/ui/asm/x86_64/may_unwind.rs
@@ -1,4 +1,3 @@
-// min-llvm-version: 13.0.0
 // only-x86_64
 // run-pass
 // needs-asm-support
diff --git a/src/test/ui/asm/x86_64/sym.rs b/src/test/ui/asm/x86_64/sym.rs
index 622365bc712af..447e11e6eabca 100644
--- a/src/test/ui/asm/x86_64/sym.rs
+++ b/src/test/ui/asm/x86_64/sym.rs
@@ -1,4 +1,3 @@
-// min-llvm-version: 12.0.1
 // only-x86_64
 // only-linux
 // needs-asm-support
diff --git a/src/test/ui/async-await/issues/issue-95307.stderr b/src/test/ui/async-await/issues/issue-95307.stderr
index 60fca71eb4b62..29aebb719d66f 100644
--- a/src/test/ui/async-await/issues/issue-95307.stderr
+++ b/src/test/ui/async-await/issues/issue-95307.stderr
@@ -9,6 +9,12 @@ LL |     async fn new() -> [u8; _];
    = note: `async` trait functions are not currently supported
    = note: consider using the `async-trait` crate: https://crates.io/crates/async-trait
 
+error: in expressions, `_` can only be used on the left-hand side of an assignment
+  --> $DIR/issue-95307.rs:7:28
+   |
+LL |     async fn new() -> [u8; _];
+   |                            ^ `_` not allowed here
+
 error[E0658]: using `_` for array lengths is unstable
   --> $DIR/issue-95307.rs:7:28
    |
@@ -18,12 +24,6 @@ LL |     async fn new() -> [u8; _];
    = note: see issue #85077 <https://github.com/rust-lang/rust/issues/85077> for more information
    = help: add `#![feature(generic_arg_infer)]` to the crate attributes to enable
 
-error: in expressions, `_` can only be used on the left-hand side of an assignment
-  --> $DIR/issue-95307.rs:7:28
-   |
-LL |     async fn new() -> [u8; _];
-   |                            ^ `_` not allowed here
-
 error: aborting due to 3 previous errors
 
 Some errors have detailed explanations: E0658, E0706.
diff --git a/src/test/ui/feature-gates/feature-gate-generic_arg_infer.normal.stderr b/src/test/ui/feature-gates/feature-gate-generic_arg_infer.normal.stderr
index 49eede4794b37..56123a983b34f 100644
--- a/src/test/ui/feature-gates/feature-gate-generic_arg_infer.normal.stderr
+++ b/src/test/ui/feature-gates/feature-gate-generic_arg_infer.normal.stderr
@@ -1,33 +1,24 @@
-error[E0658]: using `_` for array lengths is unstable
+error: in expressions, `_` can only be used on the left-hand side of an assignment
   --> $DIR/feature-gate-generic_arg_infer.rs:11:27
    |
 LL |     let _x: [u8; 3] = [0; _];
-   |                           ^
-   |
-   = note: see issue #85077 <https://github.com/rust-lang/rust/issues/85077> for more information
-   = help: add `#![feature(generic_arg_infer)]` to the crate attributes to enable
+   |                           ^ `_` not allowed here
 
 error: in expressions, `_` can only be used on the left-hand side of an assignment
-  --> $DIR/feature-gate-generic_arg_infer.rs:11:27
+  --> $DIR/feature-gate-generic_arg_infer.rs:14:18
    |
-LL |     let _x: [u8; 3] = [0; _];
-   |                           ^ `_` not allowed here
+LL |     let _y: [u8; _] = [0; 3];
+   |                  ^ `_` not allowed here
 
 error[E0658]: using `_` for array lengths is unstable
   --> $DIR/feature-gate-generic_arg_infer.rs:14:18
    |
 LL |     let _y: [u8; _] = [0; 3];
-   |                  ^
+   |                  ^ help: consider specifying the array length: `3`
    |
    = note: see issue #85077 <https://github.com/rust-lang/rust/issues/85077> for more information
    = help: add `#![feature(generic_arg_infer)]` to the crate attributes to enable
 
-error: in expressions, `_` can only be used on the left-hand side of an assignment
-  --> $DIR/feature-gate-generic_arg_infer.rs:14:18
-   |
-LL |     let _y: [u8; _] = [0; 3];
-   |                  ^ `_` not allowed here
-
 error[E0747]: type provided when a constant was expected
   --> $DIR/feature-gate-generic_arg_infer.rs:20:20
    |
@@ -37,6 +28,15 @@ LL |     let _x = foo::<_>([1,2]);
    = help: const arguments cannot yet be inferred with `_`
    = help: add `#![feature(generic_arg_infer)]` to the crate attributes to enable
 
+error[E0658]: using `_` for array lengths is unstable
+  --> $DIR/feature-gate-generic_arg_infer.rs:11:27
+   |
+LL |     let _x: [u8; 3] = [0; _];
+   |                           ^
+   |
+   = note: see issue #85077 <https://github.com/rust-lang/rust/issues/85077> for more information
+   = help: add `#![feature(generic_arg_infer)]` to the crate attributes to enable
+
 error: aborting due to 5 previous errors
 
 Some errors have detailed explanations: E0658, E0747.
diff --git a/src/test/ui/ptr_ops/issue-80309-safe.rs b/src/test/ui/ptr_ops/issue-80309-safe.rs
index f7513b6b8f447..8a4ff16694bdb 100644
--- a/src/test/ui/ptr_ops/issue-80309-safe.rs
+++ b/src/test/ui/ptr_ops/issue-80309-safe.rs
@@ -1,5 +1,4 @@
 // run-pass
-// min-llvm-version: 13.0
 // compile-flags: -O
 
 // Regression test for issue #80309
diff --git a/src/test/ui/ptr_ops/issue-80309.rs b/src/test/ui/ptr_ops/issue-80309.rs
index 5c0f4b76ceb3a..c13ce3c9cd2c1 100644
--- a/src/test/ui/ptr_ops/issue-80309.rs
+++ b/src/test/ui/ptr_ops/issue-80309.rs
@@ -1,5 +1,4 @@
 // run-pass
-// min-llvm-version: 13.0
 // compile-flags: -O
 
 // Regression test for issue #80309
diff --git a/src/test/ui/typeck/issue-100285.rs b/src/test/ui/typeck/issue-100285.rs
new file mode 100644
index 0000000000000..e206469b85f55
--- /dev/null
+++ b/src/test/ui/typeck/issue-100285.rs
@@ -0,0 +1,22 @@
+fn foo(n: i32) -> i32 {
+    for i in 0..0 {
+    //~^ ERROR: mismatched types [E0308]
+       if n < 0 {
+        return i;
+        } else if n < 10 {
+          return 1;
+        } else if n < 20 {
+          return 2;
+        } else if n < 30 {
+          return 3;
+        } else if n < 40 {
+          return 4;
+        } else {
+          return 5;
+        }
+
+    }
+    //~| help: return a value for the case when the loop has zero elements to iterate on, or consider changing the return type to account for that possibility
+}
+
+fn main() {}
diff --git a/src/test/ui/typeck/issue-100285.stderr b/src/test/ui/typeck/issue-100285.stderr
new file mode 100644
index 0000000000000..42c64b03918c5
--- /dev/null
+++ b/src/test/ui/typeck/issue-100285.stderr
@@ -0,0 +1,34 @@
+error[E0308]: mismatched types
+  --> $DIR/issue-100285.rs:2:5
+   |
+LL |   fn foo(n: i32) -> i32 {
+   |                     --- expected `i32` because of return type
+LL | /     for i in 0..0 {
+LL | |
+LL | |        if n < 0 {
+LL | |         return i;
+...  |
+LL | |
+LL | |     }
+   | |_____^ expected `i32`, found `()`
+   |
+note: the function expects a value to always be returned, but loops might run zero times
+  --> $DIR/issue-100285.rs:2:5
+   |
+LL |     for i in 0..0 {
+   |     ^^^^^^^^^^^^^ this might have zero elements to iterate on
+...
+LL |         return i;
+   |         -------- if the loop doesn't execute, this value would never get returned
+LL |         } else if n < 10 {
+LL |           return 1;
+   |           -------- if the loop doesn't execute, this value would never get returned
+LL |         } else if n < 20 {
+LL |           return 2;
+   |           -------- if the loop doesn't execute, this value would never get returned
+   = note: if the loop doesn't execute, 3 other values would never get returned
+   = help: return a value for the case when the loop has zero elements to iterate on, or consider changing the return type to account for that possibility
+
+error: aborting due to previous error
+
+For more information about this error, try `rustc --explain E0308`.