[Bug c++/95678] New: [9 Regression] ICE in dependent_type_p, at cp/pt.c:25610

[doko at debian dot org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=95678

            Bug ID: 95678
           Summary: [9 Regression] ICE in dependent_type_p, at
                    cp/pt.c:25610
           Product: gcc
           Version: 9.3.1
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: c++
          Assignee: unassigned at gcc dot gnu.org
          Reporter: doko at debian dot org
  Target Milestone: ---

seen with the gcc-9 branch 20200518, not with the gcc-10 branch.

$ cat unique.ii
# 7 "" 3
template <class b> struct c {
  using d = b;
  template <class bb, class e> auto operator()(bb l, e) -> decltype(d{l});
};
template <class f, template <class> class g> h() {
  using i = g<f>;
  int a[]{};
  unsigned j;
  i{}(a, j);
}
k() { h<int *, c>(); }

$ g++ -c -std=c++14 -Wall -fconcepts unique.ii
: In instantiation of ‘decltype (c<b>::d{l}) c<b>::operator()(bb, e) [with bb =
int*; e = unsigned int; b = int*]’:
:9:37: internal compiler error: in dependent_type_p, at cp/pt.c:25610
0x7f56f3effe0a __libc_start_main
        ../csu/libc-start.c:308
Please submit a full bug report,
with preprocessed source if appropriate.