diff --git a/ChangeLog b/ChangeLog
index eae2565bbe..23c1b711b4 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,7 @@
+Thu Jun 20 06:18:01 2013  Koichi Sasada  <ko1@atdot.net>
+
+	* gc.c (gc_profile_total_time): check objspace->profile.next_index > 0.
+
 Thu Jun 20 05:47:41 2013  Koichi Sasada  <ko1@atdot.net>
 
 	* gc.c (gc_prof_sweep_timer_start): fix merge miss.
diff --git a/gc.c b/gc.c
index 7eb6114867..5568015f0a 100644
--- a/gc.c
+++ b/gc.c
@@ -5348,10 +5348,11 @@ gc_profile_total_time(VALUE self)
 {
     double time = 0;
     rb_objspace_t *objspace = &rb_objspace;
-    size_t i;
-    size_t count = objspace->profile.next_index - 1;
 
-    if (objspace->profile.run && count > 0) {
+    if (objspace->profile.run && objspace->profile.next_index > 0) {
+	size_t i;
+	size_t count = objspace->profile.next_index - 1;
+
 	for (i = 0; i < count; i++) {
 	    time += objspace->profile.record[i].gc_time;
 	}