diff --git a/build_container/build_container_ubuntu.sh b/build_container/build_container_ubuntu.sh
index d56b493e..674cca00 100755
--- a/build_container/build_container_ubuntu.sh
+++ b/build_container/build_container_ubuntu.sh
@@ -90,19 +90,19 @@ fi
 apt-get install -y --no-install-recommends "${PACKAGES[@]}"
 
 # Set LLVM version for each cpu architecture.
-LLVM_VERSION=10.0.0
+LLVM_VERSION=11.0.1
 case $ARCH in
     'ppc64le' )
-        LLVM_DISTRO=powerpc64le-linux-ubuntu-16.04
-        LLVM_SHA256SUM=2d6298720d6aae7fcada4e909f0949d63e94fd0370d20b8882cdd91ceae7511c
+        LLVM_DISTRO=powerpc64le-linux-ubuntu-18.04
+        LLVM_SHA256SUM=a60a35f6c9f280268df8afe76f4a5349426f8b8eefd40eb885eae80b6e3647d0
         ;;
     'x86_64' )
-        LLVM_DISTRO=x86_64-linux-gnu-ubuntu-18.04
-        LLVM_SHA256SUM=b25f592a0c00686f03e3b7db68ca6dc87418f681f4ead4df4745a01d9be63843
+        LLVM_DISTRO=x86_64-linux-gnu-ubuntu-16.04
+        LLVM_SHA256SUM=67f18660231d7dd09dc93502f712613247b7b4395e6f48c11226629b250b53c5
         ;;
     'aarch64' )
         LLVM_DISTRO=aarch64-linux-gnu
-        LLVM_SHA256SUM=c2072390dc6c8b4cc67737f487ef384148253a6a97b38030e012c4d7214b7295
+        LLVM_SHA256SUM=39b3d3e3b534e327d90c77045058e5fc924b1a81d349eac2be6fb80f4a0e40d4
         ;;
 esac
 
diff --git a/build_container/build_container_windows.ps1 b/build_container/build_container_windows.ps1
index 2c195835..da4ec3b8 100644
--- a/build_container/build_container_windows.ps1
+++ b/build_container/build_container_windows.ps1
@@ -120,8 +120,8 @@ AddToPath C:\tools\ninja
 
 # LLVM to ensure a 64-bit build of the tool (VS BuildTools ships a 32-bit build)
 DownloadAndCheck $env:TEMP\LLVM-win64.exe `
-                 https://github.com/llvm/llvm-project/releases/download/llvmorg-11.0.0/LLVM-11.0.0-win64.exe `
-                 a773ee3519ecc8d68d91f0ec72ee939cbed8ded483ba8e10899dc19bccba1e22
+                 https://github.com/llvm/llvm-project/releases/download/llvmorg-11.0.1/LLVM-11.0.1-win64.exe `
+                 d17bd0e556115c30ff45e30a3f9a623af89ad6a345a5df3ac47aa8b9eabab9a7
 RunAndCheckError $env:TEMP\LLVM-win64.exe @("/S") $true
 AddToPath $env:ProgramFiles\LLVM\bin
 
diff --git a/toolchains/regenerate.sh b/toolchains/regenerate.sh
index 9f984cb2..c64bcd5c 100755
--- a/toolchains/regenerate.sh
+++ b/toolchains/regenerate.sh
@@ -38,7 +38,7 @@ esac
 
 # Bazel query is the right command so bazel won't fail itself.
 # Keep bazel versions here at most two: current main version, next version
-for BAZEL_VERSION in "3.7.2"; do
+for BAZEL_VERSION in "3.7.2" "4.0.0"; do
   for RBE_BAZEL_TARGET in ${RBE_BAZEL_TARGET_LIST}; do
     USE_BAZEL_VERSION="${BAZEL_VERSION}" bazel query ${BAZEL_QUERY_OPTIONS} ${RBE_BAZEL_TARGET}
   done