diff --git a/build_tools/llvm_version.txt b/build_tools/llvm_version.txt
index 9073213..3ce8151 100644
--- a/build_tools/llvm_version.txt
+++ b/build_tools/llvm_version.txt
@@ -1,2 +1,2 @@
-9500a7209163d6bfce7d554cb71a7c189ca5de58
+642cb7865f35ad7dbac78d716fcddaff561e8639