diff --git a/ChangeLog b/ChangeLog
index e360c3bc98..d91b700f79 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,7 @@
+Mon Jun  1 04:11:48 2015  Koichi Sasada  <ko1@atdot.net>
+
+	* gc.c , gc.h (rb_obj_info): export obj_info(VALUE) for debugging.
+
 Mon Jun  1 03:52:55 2015  Koichi Sasada  <ko1@atdot.net>
 
 	* test/ruby/test_gc.rb: increase timeout seconds for GC stressful
diff --git a/gc.c b/gc.c
index ca2a389af2..eb0a0736b2 100644
--- a/gc.c
+++ b/gc.c
@@ -8975,6 +8975,17 @@ obj_info(VALUE obj)
 }
 #endif
 
+const char *
+rb_obj_info(VALUE obj)
+{
+    if (!rb_special_const_p(obj)) {
+	return obj_info(obj);
+    }
+    else {
+	return obj_type_name(obj);
+    }
+}
+
 #if GC_DEBUG
 
 void
diff --git a/gc.h b/gc.h
index 2ba46c9250..4ddff2ddf3 100644
--- a/gc.h
+++ b/gc.h
@@ -83,6 +83,8 @@ int ruby_get_stack_grow_direction(volatile VALUE *addr);
 #endif
 #define IS_STACK_DIR_UPPER() STACK_DIR_UPPER(1,0)
 
+const char *rb_obj_info(VALUE obj);
+
 RUBY_SYMBOL_EXPORT_BEGIN
 
 /* exports for objspace module */