[24.10] bird2-babelpatch: fix unaligned access on ARMv7 targets #455
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An assembler instruction "vst1.8 {d16-d17}, [r0 :64]" requires `r0` to
be 64-bit (8-byte) aligned. However, in certain cases, `r0` was not
aligned, leading to a SIGBUS error on ARMv7 platforms:
kern.err kernel: [90636.175853] Alignment trap: not handling
instruction f4400a1f at [<00056fbc>]
kern.alert kernel: [90636.182044] Unhandled fault: alignment
exception (0x801) at 0xb6dec01c
A backtrace shows the crash occurring in `bgp_get_prefix` due to the
misaligned memory address.
Fix this issue by passing the `-mno-unaligned-access` flag to GCC/Clang.
This ensures unaligned accesses are avoided on platforms like ARMv7,
preventing alignment-related exceptions and ensuring reliable execution.
(cherry picked from commit fcce390)
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An assembler instruction "vst1.8 {d16-d17}, [r0 :64]" requires
r0to be 64-bit (8-byte) aligned. However, in certain cases,r0was not aligned, leading to a SIGBUS error on ARMv7 platforms:A backtrace shows the crash occurring in
bgp_get_prefixdue to the misaligned memory address.Fix this issue by passing the
-mno-unaligned-accessflag to GCC/Clang. This ensures unaligned accesses are avoided on platforms like ARMv7, preventing alignment-related exceptions and ensuring reliable execution.(cherry picked from commit fcce390)