diff options
| author | Faraz Vahedi <kfv@kfv.io> | 2026-05-07 23:00:47 +0000 |
|---|---|---|
| committer | Warner Losh <imp@FreeBSD.org> | 2026-06-20 00:23:29 +0000 |
| commit | 54ac231419cf09557d2f5826b1539e83db552410 (patch) | |
| tree | e818d05dcbe565ec45e3437b321a6c02bcb445c3 | |
| parent | 640ddf8571291ab2965de85f67e6065a4d7efbf8 (diff) | |
libc: Fix atomic_init for GCC atomic objects
Add a dedicated `__GNUC_ATOMICS` path that initialises via
`atomic_store_explicit(obj, value, memory_order_relaxed)`.
This ensures the required initialisation semantics without
assuming any particular object representation.
Previously, `atomic_init` on GCC fell through to the legacy
`__val` member path intended only for old struct-backed
atomic objects. For current atomic objects, this caused the
following compilation error:
> error: request for member '__val' in something not a
structure or union
As a result, valid code such as `atomic_init(&x, 1)` failed
to compile when using GCC.
This fix restores compatibility with standard-conforming
callers while other code paths remain unchanged.
Signed-off-by: Faraz Vahedi <kfv@kfv.io>
Reviewed by: imp
Pull Request: https://github.com/freebsd/freebsd-src/pull/2185
| -rw-r--r-- | sys/sys/stdatomic.h | 3 |
1 files changed, 3 insertions, 0 deletions
diff --git a/sys/sys/stdatomic.h b/sys/sys/stdatomic.h index 3e4bdd505418..c0cbb7f785b5 100644 --- a/sys/sys/stdatomic.h +++ b/sys/sys/stdatomic.h @@ -96,6 +96,9 @@ #if defined(__CLANG_ATOMICS) #define atomic_init(obj, value) __c11_atomic_init(obj, value) +#elif defined(__GNUC_ATOMICS) +#define atomic_init(obj, value) atomic_store_explicit(obj, \ + value, __ATOMIC_RELAXED) #else #define atomic_init(obj, value) ((void)((obj)->__val = (value))) #endif |