.

[gnulib.git] / m4 / realloc.m4

diff --git a/m4/realloc.m4 b/m4/realloc.m4
index b4afe93..aba1984 100644 (file)
--- a/m4/realloc.m4
+++ b/m4/realloc.m4
@@ -1,7 +1,7 @@
 #serial 1
 
 dnl From Jim Meyering.
-dnl Determine whether realloc accepts 0 as its first argument.
+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
@@ -12,13 +12,24 @@ dnl
 
 AC_DEFUN(jm_FUNC_REALLOC,
 [
+ if test x = y; then
+   dnl This code is deliberately never run via ./configure.
+   dnl FIXME: this is a gross hack to make autoheader put an entry
+   dnl for this symbol in config.h.in.
+   AC_CHECK_FUNCS(DONE_WORKING_REALLOC_CHECK)
+ fi
+ 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_kludge=HAVE_DONE_WORKING_REALLOC_CHECK
+ AC_DEFINE_UNQUOTED($ac_kludge)
+
  AC_CACHE_CHECK([for working realloc], jm_cv_func_working_realloc,
   [AC_TRY_RUN([
     char *realloc ();
     int
     main ()
     {
-      exit (realloc (0, 1) ? 0 : 1);
+      exit (realloc (0, 0) ? 0 : 1);
     }
          ],
         jm_cv_func_working_realloc=yes,