Auto merge of #143684 - nikic:llvm-21, r=<try>

rust-bors[bot] · web-flow · commit cb817598d880 · 2025-08-03T20:26:27.000Z
Update to LLVM 21
diff --git a/.gitmodules b/.gitmodules
@@ -25,7 +25,7 @@
 [submodule "src/llvm-project"]
 	path = src/llvm-project
 	url = https://github.com/rust-lang/llvm-project.git
-	branch = rustc/20.1-2025-07-13
+	branch = rustc/21.1-2025-08-01
 	shallow = true
 [submodule "src/doc/embedded-book"]
 	path = src/doc/embedded-book
diff --git a/src/ci/docker/scripts/build-clang.sh b/src/ci/docker/scripts/build-clang.sh
@@ -5,7 +5,7 @@ set -ex
 source shared.sh
 
 # Try to keep the LLVM version here in sync with src/ci/scripts/install-clang.sh
-LLVM=llvmorg-20.1.0-rc2
+LLVM=llvmorg-21.1.0-rc2
 
 mkdir llvm-project
 cd llvm-project
diff --git a/src/llvm-project b/src/llvm-project
@@ -1 +1 @@
-Subproject commit e8a2ffcf322f45b8dce82c65ab27a3e2430a6b51
+Subproject commit d35840afa50d2615835d6a836f1967c57008188a
