[Bug c++/83417] New: Pointer-to-member template parameter with auto member type dependent container type does not work (C++17)

["ambrop7 at gmail dot com" <gcc-bugzilla at gcc dot gnu dot org>]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=83417

            Bug ID: 83417
           Summary: Pointer-to-member template parameter with auto member
                    type dependent container type does not work (C++17)
           Product: gcc
           Version: 7.2.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: c++
          Assignee: unassigned at gcc dot gnu.org
          Reporter: ambrop7 at gmail dot com
  Target Milestone: ---

The following C++17 program does not compile with GCC 7.2.0 but does with Clang
5.0.0:

template <typename T, auto T::*M> void f() {}
struct A { int x; };
int main() {
    f<A, &A::x>();
    return 0;
}

The error is:

test.cpp: In function ‘int main()’:
test.cpp:4:17: error: no matching function for call to ‘f<A, &A::x>()’
     f<A, &A::x>();
                 ^
test.cpp:1:40: note: candidate: template<class T, auto T::* M> void f()
 template <typename T, auto T::*M> void f() {}
                                        ^
test.cpp:1:40: note:   template argument deduction/substitution failed:
test.cpp:4:17: error: unable to deduce ‘auto T::*’ from ‘&A::x’
     f<A, &A::x>();
                 ^
test.cpp:4:17: note:   mismatched types ‘T’ and ‘A’