.

diff --git a/m4/realloc.m4 b/m4/realloc.m4
new file mode 100644 (file)
index 0000000..b4afe93
--- /dev/null
+++ b/m4/realloc.m4
@@ -0,0 +1,33 @@
+#serial 1
+
+dnl From Jim Meyering.
+dnl Determine whether realloc accepts 0 as its first argument.
+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
+
+AC_DEFUN(jm_FUNC_REALLOC,
+[
+ AC_CACHE_CHECK([for working realloc], jm_cv_func_working_realloc,
+  [AC_TRY_RUN([
+    char *realloc ();
+    int
+    main ()
+    {
+      exit (realloc (0, 1) ? 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)
+  fi
+])