Remove stddef.h configure test

[Joseph Myers <joseph at codesourcery dot com>]

There is a configure test "for libc-friendly stddef.h", which sets a
makefile variable stddef.h that appears to be nowhere used.  It
appears the uses of this variable were removed by:

Tue Feb 21 00:10:50 1995  Roland McGrath  <roland@churchy.gnu.ai.mit.edu>

        * Makefile (headers): Remove $(stddef.h).
        * Makeconfig (stddef.h): Variable removed; now require gcc version
        >= 2.2.
        * stddef.h: File removed.

(having been added by

Wed May 26 14:44:19 1993  Roland McGrath  (roland@churchy.gnu.ai.mit.edu)

        * configure.in (autoconf checks): Add new check for a
        libc-friendly stddef.h.

so the test was of use for less than two years, before being obsolete
for over 20 years).  This patch removes the test.

Tested for x86_64 and x86 (testsuite, and that installed shared
libraries are unchanged by the patch).

2015-10-15  Joseph Myers  <joseph@codesourcery.com>

	* configure.ac (libc_cv_friendly_stddef): Remove configure test.
	* configure: Regenerated.

diff --git a/configure b/configure
index f0cd175..4b96ec7 100755
--- a/configure
+++ b/configure
@@ -5524,44 +5524,6 @@ if test $ac_verc_fail = yes; then
 fi
 
 
-{ $as_echo "$as_me:${as_lineno-$LINENO}: checking for libc-friendly stddef.h" >&5
-$as_echo_n "checking for libc-friendly stddef.h... " >&6; }
-if ${libc_cv_friendly_stddef+:} false; then :
-  $as_echo_n "(cached) " >&6
-else
-  cat confdefs.h - <<_ACEOF >conftest.$ac_ext
-/* end confdefs.h.  */
-#define __need_size_t
-#define __need_wchar_t
-#include <stddef.h>
-#define __need_NULL
-#include <stddef.h>
-int
-main ()
-{
-size_t size; wchar_t wchar;
-#ifdef offsetof
-#error stddef.h ignored __need_*
-#endif
-if (&size == NULL || &wchar == NULL) abort ();
-  ;
-  return 0;
-}
-_ACEOF
-if ac_fn_c_try_compile "$LINENO"; then :
-  libc_cv_friendly_stddef=yes
-else
-  libc_cv_friendly_stddef=no
-fi
-rm -f core conftest.err conftest.$ac_objext conftest.$ac_ext
-fi
-{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $libc_cv_friendly_stddef" >&5
-$as_echo "$libc_cv_friendly_stddef" >&6; }
-if test $libc_cv_friendly_stddef = yes; then
-  config_vars="$config_vars
-override stddef.h = # The installed <stddef.h> seems to be libc-friendly."
-fi
-
 { $as_echo "$as_me:${as_lineno-$LINENO}: checking whether we need to use -P to assemble .S files" >&5
 $as_echo_n "checking whether we need to use -P to assemble .S files... " >&6; }
 if ${libc_cv_need_minus_P+:} false; then :
diff --git a/configure.ac b/configure.ac
index 75a3a77..e2112f3 100644
--- a/configure.ac
+++ b/configure.ac
@@ -1087,24 +1087,6 @@ AC_CHECK_PROG_VER(BISON, bison, --version,
 		  [2.7*|[3-9].*|[1-9][0-9]*],
 		  BISON=no)
 
-AC_CACHE_CHECK(for libc-friendly stddef.h, libc_cv_friendly_stddef, [dnl
-AC_TRY_COMPILE(dnl
-[#define __need_size_t
-#define __need_wchar_t
-#include <stddef.h>
-#define __need_NULL
-#include <stddef.h>], [size_t size; wchar_t wchar;
-#ifdef offsetof
-#error stddef.h ignored __need_*
-#endif
-if (&size == NULL || &wchar == NULL) abort ();],
-	       libc_cv_friendly_stddef=yes,
-	       libc_cv_friendly_stddef=no)])
-if test $libc_cv_friendly_stddef = yes; then
-  config_vars="$config_vars
-override stddef.h = # The installed <stddef.h> seems to be libc-friendly."
-fi
-
 AC_CACHE_CHECK(whether we need to use -P to assemble .S files,
 	       libc_cv_need_minus_P, [dnl
 cat > conftest.S <<EOF

-- 
Joseph S. Myers
joseph@codesourcery.com