X-Git-Url: https://git.gag.com/?a=blobdiff_plain;f=m4%2Fstddef_h.m4;h=07b040abdf1cba79a58676b4ea59e41730713e6d;hb=refs%2Fheads%2Fupstream;hp=c8572de947dcd3fe6492189ec54b7811c4c9f4d0;hpb=a2016c1de6e4884f6c8ed5cc498f3bf821c25ca4;p=debian%2Fgzip

diff --git a/m4/stddef_h.m4 b/m4/stddef_h.m4
index c8572de..07b040a 100644
--- a/m4/stddef_h.m4
+++ b/m4/stddef_h.m4
@@ -1,6 +1,6 @@
-dnl A placeholder for POSIX 2008 <stddef.h>, for platforms that have issues.
-# stddef_h.m4 serial 1
-dnl Copyright (C) 2009, 2010 Free Software Foundation, Inc.
+dnl A placeholder for <stddef.h>, for platforms that have issues.
+# stddef_h.m4 serial 6
+dnl Copyright (C) 2009-2018 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.
@@ -9,10 +9,34 @@ 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 $gt_cv_c_wchar_t = no; then
     HAVE_WCHAR_T=0
     STDDEF_H=stddef.h
   fi
+
   AC_CACHE_CHECK([whether NULL can be used in arbitrary expressions],
     [gl_cv_decl_null_works],
     [AC_COMPILE_IFELSE([AC_LANG_PROGRAM([[#include <stddef.h>
@@ -24,8 +48,11 @@ AC_DEFUN([gl_STDDEF_H],
     REPLACE_NULL=1
     STDDEF_H=stddef.h
   fi
+
+  AC_SUBST([STDDEF_H])
+  AM_CONDITIONAL([GL_GENERATE_STDDEF_H], [test -n "$STDDEF_H"])
   if test -n "$STDDEF_H"; then
-    gl_CHECK_NEXT_HEADERS([stddef.h])
+    gl_NEXT_HEADERS([stddef.h])
   fi
 ])
 
@@ -33,13 +60,13 @@ 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])
-  GNULIB_[]m4_translit([$1],[abcdefghijklmnopqrstuvwxyz./-],[ABCDEFGHIJKLMNOPQRSTUVWXYZ___])=1
+  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])
-  STDDEF_H='';                   AC_SUBST([STDDEF_H])
 ])