Landing: 20a4465989b7
Project / Subsystem
gcc / i386
Date
2026-06-15
Author
Dimitar Dimitrov
Commit
20a4465989b7de0e44491d59f10b29812f2bb88c
Source
github
Perf win
No
Breaking
No
All attributes
- project
- gcc
- subsystem
- i386
- patch_id
- —
- commit_hash
- 20a4465989b7de0e44491d59f10b29812f2bb88c
- source_type
- github
- headline
- i386: Reject 16-bit modes for SSE registers without SSE2
- tldr
- Compiler now rejects invalid 16-bit SSE register modes when SSE2 is not enabled, preventing ICEs.
- author
- Dimitar Dimitrov
- outcome
- committed
- performance_win
- false
- breaking_change
- false
- series_id
- —
- series_parts
- []
- tags
-
- • i386
- • sse
- • compiler
- discussion_id_link
- —
- bugzilla_pr
- —
- date
- 2026-06-15T00:00:00.000Z
This change prevents the GCC compiler from entering an internal compiler error (ICE) when encountering 16-bit modes for SSE registers in conjunction with SSE1 without SSE2. Previously, the register allocator would attempt to create invalid subregisters, leading to failure. The fix modifies ix86_hard_regno_mode_ok to reject these invalid modes, ensuring correct behavior and stability.