1dnl A placeholder for <stddef.h>, for platforms that have issues. 2# stddef_h.m4 serial 5 3dnl Copyright (C) 2009-2018 Free Software Foundation, Inc. 4dnl This file is free software; the Free Software Foundation 5dnl gives unlimited permission to copy and/or distribute it, 6dnl with or without modifications, as long as this notice is preserved. 7 8AC_DEFUN([gl_STDDEF_H], 9[ 10 AC_REQUIRE([gl_STDDEF_H_DEFAULTS]) 11 AC_REQUIRE([gt_TYPE_WCHAR_T]) 12 STDDEF_H= 13 AC_CHECK_TYPE([max_align_t], [], [HAVE_MAX_ALIGN_T=0; STDDEF_H=stddef.h], 14 [[#include <stddef.h> 15 ]]) 16 if test $gt_cv_c_wchar_t = no; then 17 HAVE_WCHAR_T=0 18 STDDEF_H=stddef.h 19 fi 20 AC_CACHE_CHECK([whether NULL can be used in arbitrary expressions], 21 [gl_cv_decl_null_works], 22 [AC_COMPILE_IFELSE([AC_LANG_PROGRAM([[#include <stddef.h> 23 int test[2 * (sizeof NULL == sizeof (void *)) -1]; 24]])], 25 [gl_cv_decl_null_works=yes], 26 [gl_cv_decl_null_works=no])]) 27 if test $gl_cv_decl_null_works = no; then 28 REPLACE_NULL=1 29 STDDEF_H=stddef.h 30 fi 31 AC_SUBST([STDDEF_H]) 32 AM_CONDITIONAL([GL_GENERATE_STDDEF_H], [test -n "$STDDEF_H"]) 33 if test -n "$STDDEF_H"; then 34 gl_NEXT_HEADERS([stddef.h]) 35 fi 36]) 37 38AC_DEFUN([gl_STDDEF_MODULE_INDICATOR], 39[ 40 dnl Use AC_REQUIRE here, so that the default settings are expanded once only. 41 AC_REQUIRE([gl_STDDEF_H_DEFAULTS]) 42 gl_MODULE_INDICATOR_SET_VARIABLE([$1]) 43]) 44 45AC_DEFUN([gl_STDDEF_H_DEFAULTS], 46[ 47 dnl Assume proper GNU behavior unless another module says otherwise. 48 REPLACE_NULL=0; AC_SUBST([REPLACE_NULL]) 49 HAVE_MAX_ALIGN_T=1; AC_SUBST([HAVE_MAX_ALIGN_T]) 50 HAVE_WCHAR_T=1; AC_SUBST([HAVE_WCHAR_T]) 51]) 52