[lld] [lld][ELF] Demote symbols in discarded sections to Undefined. (PR #68777)

[Fangrui Song via llvm-commits]

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@@ -0,0 +1,14 @@
+# REQUIRES: x86
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MaskRay wrote:

Rebase on top of 557299c9b6464f27968904aad5429cfb1512434e

`weakref1` is test case about a symbol defined in a discarded section (`/DISCARD/`) that is weak referenced. It's controversial whether we should report an error. Since our implementation reports an error and GNU ld reports an error as well, reporting an error seems fine.

https://github.com/llvm/llvm-project/pull/68777