[lld] [LLD] [COFF] Handle undefined weak symbols in LTO (PR #70430)

[Fangrui Song via llvm-commits]

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@@ -0,0 +1,34 @@
+; REQUIRES: x86
+
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MaskRay wrote:

Add a file-level comment about the purpose as this may be less intuitive.

https://github.com/llvm/llvm-project/pull/70430