https://gcc.gnu.org/bugzilla/show_bug.cgi?id=122738
Bug ID: 122738
Summary: Accepts-invalid "struct _Atomic(int)" because _Atomic
is not defined as an alias template
Product: gcc
Version: 16.0
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: libstdc++
Assignee: unassigned at gcc dot gnu.org
Reporter: janschultke at googlemail dot com
Target Milestone: ---
> #include <stdatomic.h>
> struct _Atomic(int) x;
This code should raise an error (or warning), but is falsely accepted by GCC.
https://eel.is/c++draft/stdatomic.h.syn specifies _Atomic as expanding to an
expositon-only "std-atomic" alias template. This forbids the use of a "struct"
keyword.
This happens because libstdc++ defines _Atomic as
> #define _Atomic(_Tp) ::std::atomic<_Tp>
