https://gcc.gnu.org/bugzilla/show_bug.cgi?id=119515
Bug ID: 119515
Summary: subsumption fails with concept-id that uses a function
parameter of an abbreviated function template
Product: gcc
Version: 15.0
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: c++
Assignee: unassigned at gcc dot gnu.org
Reporter: ppalka at gcc dot gnu.org
Target Milestone: ---
$ cat testcase.C
template<class T> concept C = sizeof(T) != 1;
void f(auto x) requires C<decltype(x)> && true;
void f(auto x) requires C<decltype(x)>;
int main() {
f(0);
}
$ g++ -std=c++20 testcase.C
testcase.C: In function ‘int main()’:
testcase.C:7:4: error: call of overloaded ‘f(int)’ is ambiguous
7 | f(0);
| ~^~~
testcase.C:3:6: note: candidate: ‘void f(auto:1) requires (C<decltype(f::x)>)
&& true [with auto:1 = int]’
3 | void f(auto x) requires C<decltype(x)> && true;
| ^
testcase.C:4:6: note: candidate: ‘void f(auto:2) requires C<decltype(f::x)>
[with auto:2 = int]’
4 | void f(auto x) requires C<decltype(x)>;
| ^
