diff --git a/clang/lib/Frontend/ASTUnit.cpp b/clang/lib/Frontend/ASTUnit.cpp
index d175073..7d25ebb 100644
--- a/clang/lib/Frontend/ASTUnit.cpp
+++ b/clang/lib/Frontend/ASTUnit.cpp
@@ -1244,7 +1244,7 @@
     return TmpFile;
 
   SmallString<128> Path;
-  llvm::sys::fs::unique_file("preamble-%%%%%%.pch", Path);
+  llvm::sys::fs::createTemporaryFile("preamble", "pch", Path);
 
   return Path.str();
 }