[NFC] Fix undefined behavior with misaligned write#920
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quic-seaswara merged 2 commits intoqualcomm:mainfrom Mar 16, 2026
Merged
[NFC] Fix undefined behavior with misaligned write#920quic-seaswara merged 2 commits intoqualcomm:mainfrom
quic-seaswara merged 2 commits intoqualcomm:mainfrom
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quic-seaswara
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lenary
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quic-seaswara
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Mar 9, 2026
in emitGroup, there's an integer-sized write that triggers a sanitizer error (writing to an int-sized slot that isn't 4-byte aligned). This patch hacks around the warning by copying to a uint8_t *, not considered misaligned. The pointer is shifted by Index * sizeof(uint32_t), which should make sure nothing changes functionally. Signed-off-by: Namish Kukreja <namikukr@qti.qualcomm.com>
Signed-off-by: Namish Kukreja <namikukr@qti.qualcomm.com>
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in emitGroup, there's an integer-sized write that triggers a sanitizer error (writing to an int-sized slot that isn't 4-byte aligned). This patch removes that and uses memcpy instead, to avoid the strict aliasing violation.
The pointer is shifted by Index * sizeof(llvm::ELF::Elf32_Word), which should make sure nothing changes functionally.