dirfd: Avoid link error on AIX 7.1.

[gnulib.git] / m4 / realloc.m4

diff --git a/m4/realloc.m4 b/m4/realloc.m4
index 431ba5b..3e97b1d 100644 (file)
--- a/m4/realloc.m4
+++ b/m4/realloc.m4
@@ -1,33 +1,44 @@
-#serial 1
+# realloc.m4 serial 10
+dnl Copyright (C) 2007, 2009, 2010 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
-dnl If you use this macro in a package, you should
-dnl add the following two lines to acconfig.h:
-dnl  /* Define to rpl_realloc if the replacement function should be used.  */
-dnl  #undef realloc
-dnl
+# 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], [1],
+               [Define to 1 if your system has a GNU libc compatible 'realloc'
+                function, and to 0 otherwise.])],
+    [AC_DEFINE([HAVE_REALLOC], [0])
+     gl_REPLACE_REALLOC
+    ])
+])# gl_FUNC_REALLOC_GNU
 
-AC_DEFUN(jm_FUNC_REALLOC,
+# 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_CACHE_CHECK([for working realloc], 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 is broken.
-        jm_cv_func_working_realloc=no)
-  ])
-  if test $jm_cv_func_working_realloc = no; then
-    LIBOBJS="$LIBOBJS realloc.o"
-    AC_DEFINE_UNQUOTED(realloc, rpl_realloc)
+  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
+    gl_REPLACE_REALLOC
   fi
 ])
+
+AC_DEFUN([gl_REPLACE_REALLOC],
+[
+  AC_LIBOBJ([realloc])
+  REPLACE_REALLOC=1
+])