Index: utils/lit/lit/llvm/config.py
===================================================================
--- utils/lit/lit/llvm/config.py
+++ utils/lit/lit/llvm/config.py
@@ -369,8 +369,9 @@
         # Tweak the PATH to include the tools dir and the scripts dir.
         paths = [self.config.llvm_tools_dir]
         tools = getattr(self.config, 'clang_tools_dir', None)
+        # Put Clang first to avoid LLVM from overriding out-of-tree clang builds.
         if tools:
-            paths = paths + [tools]
+            paths = [tools] + paths
         self.with_environment('PATH', paths, append_path=True)
 
         paths = [self.config.llvm_shlib_dir, self.config.llvm_libs_dir]