[Bug testsuite/70055] New: gcc.target/i386/chkp-stropt-16.c is incompatible with glibc 2.23

["hjl.tools at gmail dot com" <gcc-bugzilla at gcc dot gnu dot org>]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=70055

            Bug ID: 70055
           Summary: gcc.target/i386/chkp-stropt-16.c is incompatible with
                    glibc 2.23
           Product: gcc
           Version: unknown
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: testsuite
          Assignee: unassigned at gcc dot gnu.org
          Reporter: hjl.tools at gmail dot com
                CC: ienkovich at gcc dot gnu.org
  Target Milestone: ---

<string.h> in glibc 2.23 has

#if defined __USE_GNU && defined __OPTIMIZE__ \
    && defined __extern_always_inline && __GNUC_PREREQ (3,2)
# if !defined _FORCE_INLINES && !defined _HAVE_STRING_ARCH_mempcpy

#undef mempcpy
#undef __mempcpy
#define mempcpy(dest, src, n) __mempcpy_inline (dest, src, n)
#define __mempcpy(dest, src, n) __mempcpy_inline (dest, src, n)

__extern_always_inline void *
__mempcpy_inline (void *__restrict __dest,
                  const void *__restrict __src, size_t __n)
{
  return (char *) memcpy (__dest, __src, __n) + __n;
}

# endif
#endif

gcc.target/i386/chkp-stropt-16.c, gcc.target/i386/chkp-stropt-4.c and
gcc.target/i386/chkp-stropt-8.c have

#define _GNU_SOURCE
#include "string.h"

void test (int *buf1, int *buf2, size_t len)
{
  mempcpy (buf1, buf2, len);
}

But GCC never sees mempcpy at all.