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[LLD]Discard invalid "DW.ref.__gxx_personality_v0" pieces in rela.eh_frame #158590

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[LLD]Discard invalid "DW.ref.__gxx_personality_v0" pieces in rela.eh_frame #158590

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5ed881d
Discard invalid "DW.ref.__gxx_personality_v0" pieces in rela.eh_frame
MaooJian Sep 15, 2025
f2b0e45
Update InputSection.cpp
MaooJian Sep 22, 2025
4496b50
Update InputSection.cpp
MaooJian Sep 22, 2025
b000330
Merge branch 'main' into patch-1
MaooJian Sep 22, 2025
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28 changes: 28 additions & 0 deletions lld/ELF/InputSection.cpp
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Original file line number Diff line number Diff line change
Expand Up @@ -491,6 +491,34 @@ void InputSection::copyRelocations(Ctx &ctx, uint8_t *buf,
p->setSymbolAndType(ctx.in.symTab->getSymbolIndex(sym), type,
ctx.arg.isMips64EL);

// Discard the invalid pieces among those named
// "DW.ref.__gxx_personality_v0".
StringRef symName = sym.getName();
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Is this limited to DW.ref.__gxx_personality_v0? Even if it is, if the underlying problem is that the pieces of the .eh_frame are optimised, but the relocations are not then why do you need to check for the particular symbol. Surely if the relocation offset doesn't exist then it would apply to all symbols.

Assuming this is specific to DW.ref.__gxx_personality_v0 then this is doing a string comparison on every relocation then checking that the section is an EhInputSection. I suggest that you reverse the order.

if (symName == "DW.ref.__gxx_personality_v0") {
if (auto *es = dyn_cast<EhInputSection>(sec)) {
auto it = partition_point(es->fdes, [=](EhSectionPiece p) {
return p.inputOff <= rel.offset;
});

if (it == es->fdes.begin() ||
it[-1].inputOff + it[-1].size <= rel.offset) {
it = partition_point(es->cies, [=](EhSectionPiece p) {
return p.inputOff <= rel.offset;
});
if (it == es->cies.begin()) {
// invalid piece
p->setSymbolAndType(0, 0, false);
continue;
}
}

if (it[-1].outputOff == -1) {
p->setSymbolAndType(0, 0, false);
continue;
}
}
}

if (sym.type == STT_SECTION) {
// We combine multiple section symbols into only one per
// section. This means we have to update the addend. That is
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