Landing: dcb8c8d3e733
Project / Subsystem
gcc / ifcvt
Date
2026-07-21
Author
Philipp Tomsich
Commit
dcb8c8d3e7333b09081f81c29358e03e73d59a12
Source
github
Perf win
No
Breaking
No
All attributes
- project
- gcc
- subsystem
- ifcvt
- patch_id
- —
- commit_hash
- dcb8c8d3e7333b09081f81c29358e03e73d59a12
- source_type
- github
- headline
- ifcvt: Avoid store flag for irreversible conditions
- tldr
- Fixes ifcvt to not emit store flags for conditions that cannot be reliably reversed.
- author
- Philipp Tomsich
- outcome
- committed
- performance_win
- false
- breaking_change
- false
- series_id
- —
- series_parts
- []
- tags
-
- • ifcvt
- • optimization
- • rtl
- • bugfix
- discussion_id_link
- —
- bugzilla_pr
- —
- date
- 2026-07-21T00:00:00.000Z
This change corrects an issue in GCC’s ifcvt optimization pass where it would incorrectly attempt to emit a store flag for comparisons that could not be reliably reversed. The noce_emit_store_flag function now checks for unknown comparison codes, preventing a crash when dealing with floating-point conditions on targets that use condition code registers.