Landing: 1bcce941ebbb
Project / Subsystem
gcc / middle-end
Date
2026-09-08
Author
Kyrylo Tkachov
Commit
1bcce941ebbb9ad97997a86432da88c8a9117d4b
Source
github
Perf win
No
Breaking
No
All attributes
- project
- gcc
- subsystem
- middle-end
- patch_id
- —
- commit_hash
- 1bcce941ebbb9ad97997a86432da88c8a9117d4b
- source_type
- github
- headline
- Use conservative store semantics for MEM_NOTRAP
- tldr
- Ensures correct non-trapping information by defaulting to conservative store semantics and re-evaluating loads.
- author
- Kyrylo Tkachov
- outcome
- committed
- performance_win
- false
- breaking_change
- false
- series_id
- —
- series_parts
- []
- tags
-
- • optimization
- • middle-end
- discussion_id_link
- —
- bugzilla_pr
- —
- date
- 2026-09-08T00:00:00.000Z
This commit refines how the MEM_NOTRAP attribute is handled, particularly for stores. Previously, set_mem_attributes derived MEM_NOTRAP from tree_could_trap_p, which describes loads. This could incorrectly mark stores to unwritable memory as non-trapping. The changes introduce MAY_STORE_P and use lhs_could_trap_p for stores, defaulting MAY_STORE_P to true. This makes the handling more conservative for stores and ensures that loads expanded with non-normal modifiers have their MEM_NOTRAP recomputed later.