make tests/test-i-ring.c C89 compliant

[Ralf Wildenhues]

Hello Jim, all,

OK to apply?

Cheers,
Ralf

2007-10-22  Ralf Wildenhues  <[EMAIL PROTECTED]>

        * tests/test-i-ring.c: Work for C89.

diff --git a/tests/test-i-ring.c b/tests/test-i-ring.c
index 0e0691a..a6aeb2b 100644
--- a/tests/test-i-ring.c
+++ b/tests/test-i-ring.c
@@ -37,9 +37,10 @@
 int
 main ()
 {
+  int o;
   I_ring ir;
   i_ring_init (&ir, -1);
-  int o = i_ring_push (&ir, 1);
+  o = i_ring_push (&ir, 1);
   ASSERT (o == -1);
   o = i_ring_push (&ir, 2);
   ASSERT (o == -1);