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[bison.git] / m4 / realloc.m4

diff --git a/m4/realloc.m4 b/m4/realloc.m4
index c8a8237472dbcfca740b5ffaec143477e0e229d7..966f0f54022f392d65b913bbe7bfc63d8577a4c5 100644 (file)
--- a/m4/realloc.m4
+++ b/m4/realloc.m4
@@ -1,4 +1,4 @@
-#serial 5
+#serial 6
 
 dnl From Jim Meyering.
 dnl Determine whether realloc works when both arguments are 0.
@@ -12,7 +12,8 @@ AC_DEFUN([jm_FUNC_REALLOC],
  AC_DEFINE(HAVE_DONE_WORKING_REALLOC_CHECK, 1,
            [Define if the realloc check has been performed. ])
 
- AC_CACHE_CHECK([for working realloc], jm_cv_func_working_realloc,
+ AC_CACHE_CHECK([whether realloc(0,0) returns a non-NULL pointer],
+                jm_cv_func_working_realloc,
   [AC_TRY_RUN([
     char *realloc ();
     int
@@ -23,10 +24,15 @@ AC_DEFUN([jm_FUNC_REALLOC],
          ],
         jm_cv_func_working_realloc=yes,
         jm_cv_func_working_realloc=no,
-        dnl When crosscompiling, assume realloc is broken.
+        dnl When crosscompiling, assume realloc(0,0) returns NULL.
         jm_cv_func_working_realloc=no)
   ])
-  if test $jm_cv_func_working_realloc = no; then
+  if test $jm_cv_func_working_realloc = yes; then
+    AC_DEFINE([HAVE_REALLOC], 1,
+             [Define to 1 if your system has a working `realloc' function,
+              and to 0 otherwise.])
+  else
+    AC_DEFINE([HAVE_REALLOC], 0)
     AC_LIBOBJ(realloc)
     AC_DEFINE(realloc, rpl_realloc,
       [Define to rpl_realloc if the replacement function should be used.])