proc: fix super_method segfault after bind

* proc.c: handle undefined iclass
  [ruby-core:85231] [Bug #14421]

From: Eric Wong <e@80x24.org>

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@62115 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

1 files changed, 1 insertions, 0 deletions

diff --git a/proc.c b/proc.c
index 4f909dac4b..86610ddfd8 100644
--- a/proc.c
+++ b/proc.c
@@ -2725,6 +2725,7 @@ method_super_method(VALUE method)
 
     TypedData_Get_Struct(method, struct METHOD, &method_data_type, data);
     iclass = data->iclass;
+    if (!iclass) return Qnil;
     super_class = RCLASS_SUPER(RCLASS_ORIGIN(iclass));
     mid = data->me->called_id;
     if (!super_class) return Qnil;