[Bug c++/70084] New: [6 Regression] va_arg ((ap), int) regression on s390*-*

[jakub at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=70084

            Bug ID: 70084
           Summary: [6 Regression] va_arg ((ap), int) regression on
                    s390*-*
           Product: gcc
           Version: 6.0
            Status: UNCONFIRMED
          Keywords: rejects-valid
          Severity: normal
          Priority: P3
         Component: c++
          Assignee: unassigned at gcc dot gnu.org
          Reporter: jakub at gcc dot gnu.org
  Target Milestone: ---

#include <stdarg.h>

struct A
{
  A (const char *f, ...);
};

A::A (const char *f, ...)
{
  va_list ap;
  va_start (ap, f);
  int i = va_arg ((ap), int);// { dg-bogus "first argument to 'va_arg' not of
type 'va_list'" }
  va_end (ap);
}

fails on s390*-* (due to -std=c++14 being the default); x86_64 backend
implementation of canonical_va_list target hook is more forgiving.