+ AC_CACHE_CHECK([whether locale.h conforms to POSIX:2001],
+ [gl_cv_header_locale_h_posix2001],
+ [AC_TRY_COMPILE([#include <locale.h>
+int x = LC_MESSAGES;], [],
+ [gl_cv_header_locale_h_posix2001=yes],
+ [gl_cv_header_locale_h_posix2001=no])])
+
+ dnl Check for <xlocale.h>.
+ AC_CHECK_HEADERS_ONCE([xlocale.h])
+ if test $ac_cv_header_xlocale_h = yes; then
+ HAVE_XLOCALE_H=1
+ dnl Check whether use of locale_t requires inclusion of <xlocale.h>,
+ dnl e.g. on MacOS X 10.5. If <locale.h> does not define locale_t by
+ dnl itself, we assume that <xlocale.h> will do so.
+ AC_CACHE_CHECK([whether locale.h defines locale_t],
+ [gl_cv_header_locale_has_locale_t],
+ [AC_TRY_COMPILE([#include <locale.h>
+locale_t x;], [],
+ [gl_cv_header_locale_has_locale_t=yes],
+ [gl_cv_header_locale_has_locale_t=no])
+ ])
+ if test $gl_cv_header_locale_has_locale_t = yes; then
+ gl_cv_header_locale_h_needs_xlocale_h=no
+ else
+ gl_cv_header_locale_h_needs_xlocale_h=yes
+ fi
+ else
+ HAVE_XLOCALE_H=0
+ gl_cv_header_locale_h_needs_xlocale_h=no
+ fi
+ AC_SUBST([HAVE_XLOCALE_H])
+
+ if test -z "$STDDEF_H" \
+ && test $gl_cv_header_locale_h_posix2001 = yes \
+ && test $gl_cv_header_locale_h_needs_xlocale_h = no; then