New upstream version 1.8

[debian/gzip] / m4 / realloc.m4

diff --git a/m4/realloc.m4 b/m4/realloc.m4
index 5925796864e033cb4e0794c9e751378f513b97c5..fc2282544dd9dcef3d9f5e661f032adc50e4fd57 100644 (file)
--- a/m4/realloc.m4
+++ b/m4/realloc.m4
@@ -1,23 +1,79 @@
-# realloc.m4 serial 9
-dnl Copyright (C) 2007, 2009 Free Software Foundation, Inc.
+# realloc.m4 serial 14
+dnl Copyright (C) 2007, 2009-2016 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.
 
+m4_version_prereq([2.70], [] ,[
+
+# This is adapted with modifications from upstream Autoconf here:
+# http://git.savannah.gnu.org/cgit/autoconf.git/commit/?id=04be2b7a29d65d9a08e64e8e56e594c91749598c
+AC_DEFUN([_AC_FUNC_REALLOC_IF],
+[
+  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
+          ]],
+          [[char *p = realloc (0, 0);
+            int result = !p;
+            free (p);
+            return result;]])
+       ],
+       [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
+
+])
+
+# 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
-    HAVE_REALLOC_POSIX=1
     AC_DEFINE([HAVE_REALLOC_POSIX], [1],
       [Define if the 'realloc' function is POSIX compliant.])
   else
-    AC_LIBOBJ([realloc])
-    HAVE_REALLOC_POSIX=0
+    REPLACE_REALLOC=1
   fi
-  AC_SUBST([HAVE_REALLOC_POSIX])
 ])