Landing: a94156b8ee71

Project / Subsystem

gcc / gcc/c++

Date

2026-05-05

Author

Rainer Orth

Commit

a94156b8ee7165c32f73f9cd11c9b8f3b8687d3b

Source

github

Perf win

No

Breaking

No

All attributes

project
gcc
subsystem
gcc/c++
patch_id
commit_hash
a94156b8ee7165c32f73f9cd11c9b8f3b8687d3b
source_type
github
headline
C++ modules: Handle ENOTSUP from posix_fallocate.
tldr
Fixes a failure when building GCC on FreeBSD with ZFS due to posix_fallocate returning ENOTSUP when creating module cache files.
author
Rainer Orth
outcome
committed
performance_win
false
breaking_change
false
series_id
series_parts
[]
tags
  • c++
  • modules
  • build
  • freebsd
discussion_id_link
bugzilla_pr
date
2026-05-05T00:00:00.000Z

GCC’s module support uses posix_fallocate to preallocate space for module cache files. On file systems like ZFS, posix_fallocate may return ENOTSUP if the operation is not supported. The compiler previously only checked for EINVAL, leading to build failures. This commit adds ENOTSUP to the error handling, resolving the issue on FreeBSD and other systems where posix_fallocate isn’t fully supported.