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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-05-06 01:16:24 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-05-06 01:16:24 +0000
commit9221dca64f0c8b5de72727491e41cf63e902eaab (patch)
treed8cbbf520eb4b5c656a54b2e36947008dcb751ad /gl/m4/stddef_h.m4
parentInitial commit. (diff)
downloadman-db-upstream.tar.xz
man-db-upstream.zip
Adding upstream version 2.8.5.upstream/2.8.5upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'gl/m4/stddef_h.m4')
-rw-r--r--gl/m4/stddef_h.m472
1 files changed, 72 insertions, 0 deletions
diff --git a/gl/m4/stddef_h.m4 b/gl/m4/stddef_h.m4
new file mode 100644
index 0000000..979e3cf
--- /dev/null
+++ b/gl/m4/stddef_h.m4
@@ -0,0 +1,72 @@
+dnl A placeholder for <stddef.h>, for platforms that have issues.
+# stddef_h.m4 serial 6
+dnl Copyright (C) 2009-2019 Free Software Foundation, Inc.
+dnl This file is free software; the Free Software Foundation
+dnl gives unlimited permission to copy and/or distribute it,
+dnl with or without modifications, as long as this notice is preserved.
+
+AC_DEFUN([gl_STDDEF_H],
+[
+ AC_REQUIRE([gl_STDDEF_H_DEFAULTS])
+ AC_REQUIRE([gt_TYPE_WCHAR_T])
+ STDDEF_H=
+
+ dnl Test whether the type max_align_t exists and whether its alignment
+ dnl "is as great as is supported by the implementation in all contexts".
+ AC_CACHE_CHECK([for good max_align_t],
+ [gl_cv_type_max_align_t],
+ [AC_COMPILE_IFELSE(
+ [AC_LANG_PROGRAM(
+ [[#include <stddef.h>
+ unsigned int s = sizeof (max_align_t);
+ #if defined __GNUC__ || defined __IBM__ALIGNOF__
+ int check1[2 * (__alignof__ (double) <= __alignof__ (max_align_t)) - 1];
+ int check2[2 * (__alignof__ (long double) <= __alignof__ (max_align_t)) - 1];
+ #endif
+ ]])],
+ [gl_cv_type_max_align_t=yes],
+ [gl_cv_type_max_align_t=no])
+ ])
+ if test $gl_cv_type_max_align_t = no; then
+ HAVE_MAX_ALIGN_T=0
+ STDDEF_H=stddef.h
+ fi
+
+ if test $gt_cv_c_wchar_t = no; then
+ HAVE_WCHAR_T=0
+ STDDEF_H=stddef.h
+ fi
+
+ AC_CACHE_CHECK([whether NULL can be used in arbitrary expressions],
+ [gl_cv_decl_null_works],
+ [AC_COMPILE_IFELSE([AC_LANG_PROGRAM([[#include <stddef.h>
+ int test[2 * (sizeof NULL == sizeof (void *)) -1];
+]])],
+ [gl_cv_decl_null_works=yes],
+ [gl_cv_decl_null_works=no])])
+ if test $gl_cv_decl_null_works = no; then
+ REPLACE_NULL=1
+ STDDEF_H=stddef.h
+ fi
+
+ AC_SUBST([STDDEF_H])
+ AM_CONDITIONAL([GL_GENERATE_STDDEF_H], [test -n "$STDDEF_H"])
+ if test -n "$STDDEF_H"; then
+ gl_NEXT_HEADERS([stddef.h])
+ fi
+])
+
+AC_DEFUN([gl_STDDEF_MODULE_INDICATOR],
+[
+ dnl Use AC_REQUIRE here, so that the default settings are expanded once only.
+ AC_REQUIRE([gl_STDDEF_H_DEFAULTS])
+ gl_MODULE_INDICATOR_SET_VARIABLE([$1])
+])
+
+AC_DEFUN([gl_STDDEF_H_DEFAULTS],
+[
+ dnl Assume proper GNU behavior unless another module says otherwise.
+ REPLACE_NULL=0; AC_SUBST([REPLACE_NULL])
+ HAVE_MAX_ALIGN_T=1; AC_SUBST([HAVE_MAX_ALIGN_T])
+ HAVE_WCHAR_T=1; AC_SUBST([HAVE_WCHAR_T])
+])