diff --git a/.gitmodules b/.gitmodules
index cca60e337d2..9a664b65098 100644
--- a/.gitmodules
+++ b/.gitmodules
@@ -34,7 +34,7 @@
 [submodule "src/llvm-project"]
 	path = src/llvm-project
 	url = https://github.com/rust-lang/llvm-project.git
-	branch = rustc/14.0-2022-06-20
+	branch = rustc/15.0-2022-08-09
 [submodule "src/doc/embedded-book"]
 	path = src/doc/embedded-book
 	url = https://github.com/rust-embedded/book.git
diff --git a/src/llvm-project b/src/llvm-project
index 8b6b5014fda..639388a05f2 160000
--- a/src/llvm-project
+++ b/src/llvm-project
@@ -1 +1 @@
-Subproject commit 8b6b5014fdad3a750f7242a6bfdcad83619498d4
+Subproject commit 639388a05f25772fb23eea5b1045e7df83bcfaa7