Landing: 0f485cf70171
Project / Subsystem
gcc / cfgexpand
Date
2026-07-14
Author
Jakub Jelinek
Commit
0f485cf70171a41ea39deec0a8b65aad0b9d2a9b
Source
github
Perf win
No
Breaking
No
All attributes
- project
- gcc
- subsystem
- cfgexpand
- patch_id
- —
- commit_hash
- 0f485cf70171a41ea39deec0a8b65aad0b9d2a9b
- source_type
- github
- headline
- cfgexpand: Align ASan variable block to stack alignment.
- tldr
- Ensures AddressSanitizer variable allocation respects stack alignment needs.
- author
- Jakub Jelinek
- outcome
- committed
- performance_win
- false
- breaking_change
- false
- series_id
- —
- series_parts
- []
- tags
-
- • asan
- • stack
- • alignment
- • compiler
- • bugfix
- discussion_id_link
- —
- bugzilla_pr
- —
- date
- 2026-07-14T00:00:00.000Z
This commit ensures that the block of variables used by AddressSanitizer (data.asan_alignb) is properly aligned with the stack’s alignment requirements (crtl->stack_alignment_needed). If the stack alignment needed is greater than the current ASan allocation alignment, it could lead to misaligned stack allocations for subsequent data, such as vector modes with large alignment requirements. The change updates data.asan_alignb to the maximum of its current value and the stack alignment needed, preventing potential alignment issues.