link.MachO.UnwindInfo: Handle u24 overflow for CU records pointing to DWARF.
#23011
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andrewrk
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Feb 25, 2025
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Thanks for figuring it out!
Based on this comment, wouldn't saturation be better than zero? If that's not the case, the comment should explain why that's not the case.
Edit: the LLVM comment answers the question. How about copy pasting their comment instead of this new one?
it explains why zero is used instead of saturation
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kubkon
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Mar 2, 2025
| // just encode zero -- the start of the section is always the start | ||
| // of a CFI record. | ||
| const hint = std.math.cast(u24, fde.out_offset) orelse 0; | ||
| rec.enc.setDwarfSectionOffset(hint); |
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Great find! Is there a test case demonstrating the issue in action I wonder?
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Closes #23010.
Relevant LLD code (thanks @Rexicon226): https://github.com/llvm/llvm-project/blob/e67cd152cf4d0344efba19985b005dae15e6bde0/lld/MachO/UnwindInfoSection.cpp#L361-L368