Got rid of the useless SIZE_MAX macro.

  * src/vasprintf.c: replaced SIZE_MAX by (size_t) -1, already used
    in some other files.
  * acinclude.m4: no longer use gl_SIZE_MAX (from m4/size_max.m4).
  * Removed m4/size_max.m4 as it is no longer needed (note that the
    definition of SIZE_MAX by this file was unnecessarily complex
    and potentially incorrect on some platforms).

git-svn-id: svn://scm.gforge.inria.fr/svn/mpfr/trunk@11852 280ebfd0-de03-0410-8827-d642c229c3f4

3 files changed, 6 insertions, 83 deletions

diff --git a/acinclude.m4 b/acinclude.m4
index 01e01e666..dbb099e42 100644
--- a/acinclude.m4
+++ b/acinclude.m4
@@ -69,9 +69,6 @@ AC_CHECK_MEMBERS([struct lconv.decimal_point, struct lconv.thousands_sep],,,
 dnl Check how to get `alloca'
 AC_FUNC_ALLOCA
 
-dnl SIZE_MAX macro
-gl_SIZE_MAX
-
 dnl va_copy macro
 AC_MSG_CHECKING([how to copy va_list])
 AC_LINK_IFELSE([AC_LANG_PROGRAM([[
diff --git a/m4/size_max.m4 b/m4/size_max.m4
deleted file mode 100644
index aa16e1a12..000000000
--- a/m4/size_max.m4
+++ /dev/null
@@ -1,73 +0,0 @@
-# size_max.m4 serial 6
-dnl Copyright (C) 2003, 2005-2006, 2010, 2012 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.
-
-dnl From Bruno Haible.
-dnl Change by Vincent Lefevre: added <inttypes.h> for consistency with MPFR
-dnl Update with autoupdate.
-
-AC_DEFUN([gl_SIZE_MAX],
-[
-  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], [
-    gl_cv_size_max=
-    AC_EGREP_CPP([Found it], [
-#include <limits.h>
-#ifdef HAVE_INTTYPES_H
-# include <inttypes.h>
-#endif
-#if HAVE_STDINT_H
-# include <stdint.h>
-#endif
-#ifdef SIZE_MAX
-Found it
-#endif
-], gl_cv_size_max=yes)
-    if test -z "$gl_cv_size_max"; then
-      dnl Define it ourselves. Here we assume that the type 'size_t' is not wider
-      dnl than the type 'unsigned long'. Try hard to find a definition that can
-      dnl be used in a preprocessor #if, i.e. doesn't contain a cast.
-      AC_COMPUTE_INT([size_t_bits_minus_1], [sizeof (size_t) * CHAR_BIT - 1],
-        [#include <stddef.h>
-#include <limits.h>], size_t_bits_minus_1=)
-      AC_COMPUTE_INT([fits_in_uint], [sizeof (size_t) <= sizeof (unsigned int)],
-        [#include <stddef.h>], fits_in_uint=)
-      if test -n "$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_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
-        dnl might be cross-compiling from a 32-bit platform to a 64-bit platform.
-        if test $fits_in_uint = 1; then
-          gl_cv_size_max="(((1U << $size_t_bits_minus_1) - 1) * 2 + 1)"
-        else
-          gl_cv_size_max="(((1UL << $size_t_bits_minus_1) - 1) * 2 + 1)"
-        fi
-      else
-        dnl Shouldn't happen, but who knows...
-        gl_cv_size_max='((size_t)~(size_t)0)'
-      fi
-    fi
-  ])
-  AC_MSG_RESULT([$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 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])])
-])
diff --git a/src/vasprintf.c b/src/vasprintf.c
index 9fcc53dd4..3dc40e6cc 100644
--- a/src/vasprintf.c
+++ b/src/vasprintf.c
@@ -36,8 +36,8 @@ http://www.gnu.org/licenses/ or write to the Free Software Foundation, Inc.,
 /* Note: Due to limitations from the C standard and GMP, if
    size_t < unsigned int (which is allowed by the C standard but unlikely
    to occur on any platform), the behavior is undefined for output that
-   would reach SIZE_MAX (if the result cannot be delivered, there should
-   be an assertion failure, but this could not be tested). */
+   would reach SIZE_MAX = (size_t) -1 (if the result cannot be delivered,
+   there should be an assertion failure, but this could not be tested). */
 
 #ifdef HAVE_CONFIG_H
 # include "config.h"
@@ -66,7 +66,6 @@ http://www.gnu.org/licenses/ or write to the Free Software Foundation, Inc.,
 
 #if defined (__cplusplus)
 #include <cstddef>
-#define __STDC_LIMIT_MACROS   /* SIZE_MAX defined with <stdint.h> inclusion */
 #else
 #include <stddef.h>             /* for ptrdiff_t */
 #endif
@@ -598,7 +597,7 @@ buffer_widen (struct string_buffer *b, size_t len)
   MPFR_ASSERTD (*b->curr == '\0');
   MPFR_ASSERTD (pos < b->size);
 
-  MPFR_ASSERTN (b->size < SIZE_MAX - n);
+  MPFR_ASSERTN (b->size < ((size_t) -1) - n);
 
   b->start =
     (char *) mpfr_reallocate_func (b->start, b->size, b->size + n);
@@ -623,7 +622,7 @@ buffer_cat (struct string_buffer *b, const char *s, size_t len)
   if (b->size != 0)
     {
       MPFR_ASSERTD (*b->curr == '\0');
-      MPFR_ASSERTN (b->size < SIZE_MAX - len);
+      MPFR_ASSERTN (b->size < ((size_t) -1) - len);
       if (MPFR_UNLIKELY (b->curr + len >= b->start + b->size))
         buffer_widen (b, len);
 
@@ -651,7 +650,7 @@ buffer_pad (struct string_buffer *b, const char c, const size_t n)
   if (b->size != 0)
     {
       MPFR_ASSERTD (*b->curr == '\0');
-      MPFR_ASSERTN (b->size < SIZE_MAX - n);
+      MPFR_ASSERTN (b->size < ((size_t) -1) - n);
       if (MPFR_UNLIKELY (b->curr + n >= b->start + b->size))
         buffer_widen (b, n);
 
@@ -700,7 +699,7 @@ buffer_sandwich (struct string_buffer *b, char *str, size_t len,
           char *oldcurr;
 
           MPFR_ASSERTD (*b->curr == '\0');
-          MPFR_ASSERTN (b->size < SIZE_MAX - fullsize);
+          MPFR_ASSERTN (b->size < ((size_t) -1) - fullsize);
           if (MPFR_UNLIKELY (b->curr + fullsize >= b->start + b->size))
             buffer_widen (b, fullsize);