[lld] [LLD] Tombstone LocalTU entry in .debug_names (PR #70701)

[Alexander Yermolovich via llvm-commits]

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@@ -918,7 +917,8 @@ void InputSection::relocateNonAlloc(uint8_t *buf, ArrayRef<RelTy> rels) {
       continue;
 
     if (tombstone ||
-        (isDebug && (type == target.symbolicRel || expr == R_DTPREL))) {
+        ((isDebug && (type == target.symbolicRel || expr == R_DTPREL))) ||
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ayermolo wrote:

Well basically that condition checks if relocation is 64bit: R_X86_64_64 (type == 1).
Primarily used in .debug_addr. Incidentally why DWARF64 tests works without adding isDebugNames to that condition. since for .debug_names relocation type is controlled by DWARF32 vs DWARF64.
Slightly more interesting case is expr == R_DTPREL. Since pretty much all relocs in debug sections are ABS. Looks like that relocation is used to reference TLS symbols. Learned something new today.

https://github.com/llvm/llvm-project/pull/70701