Source
--- js/src/jsinterp.cpp.orig 2013-10-29 19:59:43.000000000 +0100
+++ js/src/jsinterp.cpp 2013-10-29 20:01:44.000000000 +0100
BEGIN_CASE(JSOP_LEAVEFORLETIN)
BEGIN_CASE(JSOP_LEAVEBLOCKEXPR)
{
+#ifdef DEBUG
DebugOnly<uint32_t> blockDepth = regs.fp()->blockChain().stackDepth();
+#endif
regs.fp()->popBlock(cx);