https://gcc.gnu.org/bugzilla/show_bug.cgi?id=122650
Bug ID: 122650
Summary: Redeclarations of function which add noreturn
attributes should be diagnosed
Product: gcc
Version: 16.0
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: c
Assignee: unassigned at gcc dot gnu.org
Reporter: luigighiron at gmail dot com
Target Milestone: ---
The following code is incorrectly accepted by GCC:
int x(),x[[noreturn]]();
int main(){}
> The first declaration of a function shall specify the noreturn attribute if
> any declaration of that function specifies the noreturn attribute. If a
> function is declared with the noreturn attribute in one translation unit and
> the same function is declared without the noreturn attribute in another
> translation unit, the behavior is undefined.
Section 6.7.13.7 "The noreturn and _Noreturn attributes" Paragraph 3 ISO/IEC
9899:2024
The first declaration of x doesn't specify noreturn and at least one other
redeclaration does, so this is invalid. GCC correctly diagnoses this in C++
mode. Also, the _Noreturn function specifier doesn't appear to have any wording
to this effect so this restriction shouldn't extend to that.
Clang appears to have the same issue as GCC, and correctly diagnoses in C++
mode too.
