[lld] [lld][ELF] Add /PASSTHRU/. #65087 (PR #84287)

[Bevin Hansson via llvm-commits]

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@@ -310,6 +310,7 @@ std::string InputSectionBase::getObjMsg(uint64_t off) const {
 }
 
 InputSection InputSection::discarded(nullptr, 0, 0, 0, ArrayRef<uint8_t>(), "");
+InputSection InputSection::passthru(nullptr, 0, 0, 0, ArrayRef<uint8_t>(), "");
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bevin-hansson wrote:

Perhaps this is abuse of InputSection. Maybe it should be a marker OutputSection instead.

https://github.com/llvm/llvm-project/pull/84287