1 dnl A placeholder for POSIX 2008 <stddef.h>, for platforms that have issues. 2 # stddef_h.m4 serial 4 3 dnl Copyright (C) 2009-2012 Free Software Foundation, Inc. 4 dnl This file is free software; the Free Software Foundation 5 dnl gives unlimited permission to copy and/or distribute it, 6 dnl with or without modifications, as long as this notice is preserved. 7 8 AC_DEFUN([gl_STDDEF_H], 9 [ 10 AC_REQUIRE([gl_STDDEF_H_DEFAULTS]) 11 AC_REQUIRE([gt_TYPE_WCHAR_T]) 12 STDDEF_H= 13 if test $gt_cv_c_wchar_t = no; then 14 HAVE_WCHAR_T=0 15 STDDEF_H=stddef.h 16 fi 17 AC_CACHE_CHECK([whether NULL can be used in arbitrary expressions], 18 [gl_cv_decl_null_works], 19 [AC_COMPILE_IFELSE([AC_LANG_PROGRAM([[#include <stddef.h> 20 int test[2 * (sizeof NULL == sizeof (void *)) -1]; 21 ]])], 22 [gl_cv_decl_null_works=yes], 23 [gl_cv_decl_null_works=no])]) 24 if test $gl_cv_decl_null_works = no; then 25 REPLACE_NULL=1 26 STDDEF_H=stddef.h 27 fi 28 AC_SUBST([STDDEF_H]) 29 AM_CONDITIONAL([GL_GENERATE_STDDEF_H], [test -n "$STDDEF_H"]) 30 if test -n "$STDDEF_H"; then 31 gl_NEXT_HEADERS([stddef.h]) 32 fi 33 ]) 34 35 AC_DEFUN([gl_STDDEF_MODULE_INDICATOR], 36 [ 37 dnl Use AC_REQUIRE here, so that the default settings are expanded once only. 38 AC_REQUIRE([gl_STDDEF_H_DEFAULTS]) 39 gl_MODULE_INDICATOR_SET_VARIABLE([$1]) 40 ]) 41 42 AC_DEFUN([gl_STDDEF_H_DEFAULTS], 43 [ 44 dnl Assume proper GNU behavior unless another module says otherwise. 45 REPLACE_NULL=0; AC_SUBST([REPLACE_NULL]) 46 HAVE_WCHAR_T=1; AC_SUBST([HAVE_WCHAR_T]) 47 ]) 48
