[Bug c++/65075] New: [5 Regression] constexpr regression

["jakub at gcc dot gnu.org" <gcc-bugzilla at gcc dot gnu dot org>]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=65075

            Bug ID: 65075
           Summary: [5 Regression] constexpr regression
           Product: gcc
           Version: 5.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: c++
          Assignee: unassigned at gcc dot gnu.org
          Reporter: jakub at gcc dot gnu.org

typedef void (*E) ();
template <class T>
constexpr E
bar ()
{
  return []() {};
}
void
foo ()
{
  (bar<int> ()) ();
}

is rejected since r215954 aka PR55250 with -std=c++11:
error: body of constexpr function âconstexpr void (* bar())() [with T = int; E
= void (*)()]â not a return-statement
The body is a return statement, just perhaps with some extra artificial
statements created for the lambda.