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-rw-r--r--m4/size_max.m447
1 files changed, 32 insertions, 15 deletions
diff --git a/m4/size_max.m4 b/m4/size_max.m4
index bfba811eb..7e192d5e9 100644
--- a/m4/size_max.m4
+++ b/m4/size_max.m4
@@ -1,5 +1,5 @@
-# size_max.m4 serial 5
-dnl Copyright (C) 2003, 2005-2006 Free Software Foundation, Inc.
+# size_max.m4 serial 10
+dnl Copyright (C) 2003, 2005-2006, 2008-2014 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.
@@ -8,10 +8,9 @@ dnl From Bruno Haible.
AC_DEFUN([gl_SIZE_MAX],
[
- AC_CHECK_HEADERS(stdint.h)
+ AC_CHECK_HEADERS([stdint.h])
dnl First test whether the system already has SIZE_MAX.
- AC_MSG_CHECKING([for SIZE_MAX])
- AC_CACHE_VAL([gl_cv_size_max], [
+ AC_CACHE_CHECK([for SIZE_MAX], [gl_cv_size_max], [
gl_cv_size_max=
AC_EGREP_CPP([Found it], [
#include <limits.h>
@@ -21,24 +20,28 @@ AC_DEFUN([gl_SIZE_MAX],
#ifdef SIZE_MAX
Found it
#endif
-], gl_cv_size_max=yes)
+], [gl_cv_size_max=yes])
if test -z "$gl_cv_size_max"; then
dnl Define it ourselves. Here we assume that the type 'size_t' is not wider
dnl than the type 'unsigned long'. Try hard to find a definition that can
dnl be used in a preprocessor #if, i.e. doesn't contain a cast.
- _AC_COMPUTE_INT([sizeof (size_t) * CHAR_BIT - 1], size_t_bits_minus_1,
+ AC_COMPUTE_INT([size_t_bits_minus_1], [sizeof (size_t) * CHAR_BIT - 1],
[#include <stddef.h>
-#include <limits.h>], size_t_bits_minus_1=)
- _AC_COMPUTE_INT([sizeof (size_t) <= sizeof (unsigned int)], fits_in_uint,
- [#include <stddef.h>], fits_in_uint=)
+#include <limits.h>], [size_t_bits_minus_1=])
+ AC_COMPUTE_INT([fits_in_uint], [sizeof (size_t) <= sizeof (unsigned int)],
+ [#include <stddef.h>], [fits_in_uint=])
if test -n "$size_t_bits_minus_1" && test -n "$fits_in_uint"; then
if test $fits_in_uint = 1; then
dnl Even though SIZE_MAX fits in an unsigned int, it must be of type
dnl 'unsigned long' if the type 'size_t' is the same as 'unsigned long'.
- AC_TRY_COMPILE([#include <stddef.h>
- extern size_t foo;
- extern unsigned long foo;
- ], [], fits_in_uint=0)
+ AC_COMPILE_IFELSE(
+ [AC_LANG_PROGRAM(
+ [[#include <stddef.h>
+ extern size_t foo;
+ extern unsigned long foo;
+ ]],
+ [[]])],
+ [fits_in_uint=0])
fi
dnl We cannot use 'expr' to simplify this expression, because 'expr'
dnl works only with 'long' integers in the host environment, while we
@@ -54,9 +57,23 @@ Found it
fi
fi
])
- AC_MSG_RESULT([$gl_cv_size_max])
if test "$gl_cv_size_max" != yes; then
AC_DEFINE_UNQUOTED([SIZE_MAX], [$gl_cv_size_max],
[Define as the maximum value of type 'size_t', if the system doesn't define it.])
fi
+ dnl Don't redefine SIZE_MAX in config.h if config.h is re-included after
+ dnl <stdint.h>. Remember that the #undef in AH_VERBATIM gets replaced with
+ dnl #define by AC_DEFINE_UNQUOTED.
+ AH_VERBATIM([SIZE_MAX],
+[/* Define as the maximum value of type 'size_t', if the system doesn't define
+ it. */
+#ifndef SIZE_MAX
+# undef SIZE_MAX
+#endif])
+])
+
+dnl Autoconf >= 2.61 has AC_COMPUTE_INT built-in.
+dnl Remove this when we can assume autoconf >= 2.61.
+m4_ifdef([AC_COMPUTE_INT], [], [
+ AC_DEFUN([AC_COMPUTE_INT], [_AC_COMPUTE_INT([$2],[$1],[$3],[$4])])
])