X-Git-Url: http://erislabs.net/gitweb/?a=blobdiff_plain;f=m4%2Frealloc.m4;h=d477fb470b23259d4b6d88bda502bc48c10a39d5;hb=bbfcd2f1a92c9bdbb8d7d7d0a8a8c6665c316747;hp=7695e89c852fb1cc57064d2e3caf85bbdcf8e971;hpb=ef2670d2fd07cccb23c948c3b96af692e067f8ff;p=gnulib.git

diff --git a/m4/realloc.m4 b/m4/realloc.m4
index 7695e89c8..d477fb470 100644
--- a/m4/realloc.m4
+++ b/m4/realloc.m4
@@ -1,35 +1,76 @@
-#serial 6
+# realloc.m4 serial 13
+dnl Copyright (C) 2007, 2009-2013 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 Jim Meyering.
-dnl Determine whether realloc works when both arguments are 0.
-dnl If it doesn't, arrange to use the replacement function.
-dnl
+m4_version_prereq([2.70], [] ,[
 
-AC_DEFUN([jm_FUNC_REALLOC],
+# This is taken from the following Autoconf patch:
+# http://git.savannah.gnu.org/gitweb/?p=autoconf.git;a=commitdiff;h=7fbb553727ed7e0e689a17594b58559ecf3ea6e9
+AC_DEFUN([_AC_FUNC_REALLOC_IF],
 [
- dnl xmalloc.c requires that this symbol be defined so it doesn't
- dnl mistakenly use a broken realloc -- as it might if this test were omitted.
- AC_DEFINE(HAVE_DONE_WORKING_REALLOC_CHECK, 1,
-           [Define if the realloc check has been performed. ])
+  AC_REQUIRE([AC_HEADER_STDC])dnl
+  AC_REQUIRE([AC_CANONICAL_HOST])dnl for cross-compiles
+  AC_CHECK_HEADERS([stdlib.h])
+  AC_CACHE_CHECK([for GNU libc compatible realloc],
+    [ac_cv_func_realloc_0_nonnull],
+    [AC_RUN_IFELSE(
+       [AC_LANG_PROGRAM(
+          [[#if defined STDC_HEADERS || defined HAVE_STDLIB_H
+            # include <stdlib.h>
+            #else
+            char *realloc ();
+            #endif
+          ]],
+          [[return ! realloc (0, 0);]])
+       ],
+       [ac_cv_func_realloc_0_nonnull=yes],
+       [ac_cv_func_realloc_0_nonnull=no],
+       [case "$host_os" in
+          # Guess yes on platforms where we know the result.
+          *-gnu* | freebsd* | netbsd* | openbsd* \
+          | hpux* | solaris* | cygwin* | mingw*)
+            ac_cv_func_realloc_0_nonnull=yes ;;
+          # If we don't know, assume the worst.
+          *) ac_cv_func_realloc_0_nonnull=no ;;
+        esac
+       ])
+    ])
+  AS_IF([test $ac_cv_func_realloc_0_nonnull = yes], [$1], [$2])
+])# AC_FUNC_REALLOC
 
- AC_CACHE_CHECK([whether realloc(0,0) returns a non-NULL pointer],
-                jm_cv_func_working_realloc,
-  [AC_TRY_RUN([
-    char *realloc ();
-    int
-    main ()
-    {
-      exit (realloc (0, 0) ? 0 : 1);
-    }
-	  ],
-	 jm_cv_func_working_realloc=yes,
-	 jm_cv_func_working_realloc=no,
-	 dnl When crosscompiling, assume realloc(0,0) returns NULL.
-	 jm_cv_func_working_realloc=no)
-  ])
-  if test $jm_cv_func_working_realloc = no; then
-    AC_LIBOBJ(realloc)
-    AC_DEFINE(realloc, rpl_realloc,
-      [Define to rpl_realloc if the replacement function should be used.])
+])
+
+# gl_FUNC_REALLOC_GNU
+# -------------------
+# Test whether 'realloc (0, 0)' is handled like in GNU libc, and replace
+# realloc if it is not.
+AC_DEFUN([gl_FUNC_REALLOC_GNU],
+[
+  AC_REQUIRE([gl_STDLIB_H_DEFAULTS])
+  dnl _AC_FUNC_REALLOC_IF is defined in Autoconf.
+  _AC_FUNC_REALLOC_IF(
+    [AC_DEFINE([HAVE_REALLOC_GNU], [1],
+               [Define to 1 if your system has a GNU libc compatible 'realloc'
+                function, and to 0 otherwise.])],
+    [AC_DEFINE([HAVE_REALLOC_GNU], [0])
+     REPLACE_REALLOC=1
+    ])
+])# gl_FUNC_REALLOC_GNU
+
+# gl_FUNC_REALLOC_POSIX
+# ---------------------
+# Test whether 'realloc' is POSIX compliant (sets errno to ENOMEM when it
+# fails), and replace realloc if it is not.
+AC_DEFUN([gl_FUNC_REALLOC_POSIX],
+[
+  AC_REQUIRE([gl_STDLIB_H_DEFAULTS])
+  AC_REQUIRE([gl_CHECK_MALLOC_POSIX])
+  if test $gl_cv_func_malloc_posix = yes; then
+    AC_DEFINE([HAVE_REALLOC_POSIX], [1],
+      [Define if the 'realloc' function is POSIX compliant.])
+  else
+    REPLACE_REALLOC=1
   fi
 ])