[llvm] [Bazel] Make LLVM and Clang config headers configurable (PR #126729)

[Fangrui Song via llvm-commits]

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@@ -86,12 +86,15 @@ def main(args):
                 os.path.join(args.overlay, relpath), os.path.join(args.target, relpath)
             )
 
-        for src_entry in os.listdir(os.path.join(args.src, rel_root)):
-            if src_entry not in dirs:
-                relpath = os.path.join(rel_root, src_entry)
-                _symlink_abs(
-                    os.path.join(args.src, relpath), os.path.join(args.target, relpath)
-                )
+        src_path = os.path.join(args.src, rel_root)
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MaskRay wrote:

You might want to write some comments since this is getting complex

https://github.com/llvm/llvm-project/pull/126729