[lld] [ELF] Demote symbols in /DISCARD/ discarded sections to Undefined (PR #69295)

[Fangrui Song via llvm-commits]

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@@ -3023,7 +3056,6 @@ void LinkerDriver::link(opt::InputArgList &args) {
 
   // Garbage collection and removal of shared symbols from unused shared objects.
   invokeELFT(markLive,);
-  demoteSharedAndLazySymbols();
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MaskRay wrote:

Moved `demoteSymbols` in e9b9a1d3202d86d9eb2b49c6463fde0f15f9dc94 and merged two symtab iterations in fc5d815d547e534df8fdb997899e0cffc65b9e35

https://github.com/llvm/llvm-project/pull/69295