vm_insnhelper.c: break from nested rescue

* vm_insnhelper.c (vm_throw_start): search the target to break
  from a block with nested rescue, from the nested blocks.
  [ruby-core:67765] [Bug #10775] [Fix GH-820]

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@49390 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

ChangeLog

@@ -1,3 +1,9 @@
+Fri Jan 23 23:57:05 2015  Misumi Rize  <r@ayase-e.li>
+
+	* vm_insnhelper.c (vm_throw_start): search the target to break
+	  from a block with nested rescue, from the nested blocks.
+	  [ruby-core:67765] [Bug #10775] [Fix GH-820]
+
 Fri Jan 23 20:00:59 2015  Nobuyoshi Nakada  <nobu@ruby-lang.org>
 
 	* marshal.c (w_object, marshal_dump): use indetity tables for

bootstraptest/test_block.rb

@@ -597,3 +597,17 @@ assert_equal 'true', %q{
   C1.new.foo{}
 }
 
+assert_equal 'ok', %q{
+  1.times do
+    begin
+      raise
+    rescue
+      begin
+        raise
+      rescue
+        break
+      end
+    end
+  end
+  'ok'
+}

vm_insnhelper.c

@@ -609,13 +609,11 @@ vm_throw_start(rb_thread_t * const th, rb_control_frame_t * const reg_cfp, int s
 	rb_iseq_t *base_iseq = GET_ISEQ();
 	escape_cfp = reg_cfp;
 
-      search_parent:
-	if (base_iseq->type != ISEQ_TYPE_BLOCK) {
+	while (base_iseq->type != ISEQ_TYPE_BLOCK) {
 	    if (escape_cfp->iseq->type == ISEQ_TYPE_CLASS) {
 		escape_cfp = RUBY_VM_PREVIOUS_CONTROL_FRAME(escape_cfp);
 		ep = escape_cfp->ep;
 		base_iseq = escape_cfp->iseq;
-		goto search_parent;
 	    }
 	    else {
 		ep = VM_EP_PREV_EP(ep);