https://gcc.gnu.org/bugzilla/show_bug.cgi?id=97450
Bug ID: 97450
Summary: [concepts] Bogus errors during constraint
normalization
Product: gcc
Version: 11.0
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: c++
Assignee: unassigned at gcc dot gnu.org
Reporter: ppalka at gcc dot gnu.org
Target Milestone: ---
We accept the first static_assert below without error, but we reject the second
due to seemingly bogus errors during normalization of E's
constraint-expression.
$ cat testcase.C
template<class T> concept C = true;
template<class T> concept D = C<typename T::type>;
template<class T> concept E = D<int>;
static_assert(D<int>); // OK
static_assert(E<int>); // error
$ g++ -std=c++20 testcase.C
testcase.C:5:22: error: ‘int’ is not a class, struct, or union type
5 | static_assert(E<int>); // error
| ^
testcase.C:5:22: error: ‘int’ is not a class, struct, or union type
testcase.C:5:15: error: non-constant condition for static assertion
5 | static_assert(E<int>); // error
| ^~~~~~
testcase.C:5:15: error: ‘int’ is not a class, struct, or union type
