for part of some other context-stack related struct.
p4raw-id: //depot/perl@33655
# define CX_ITERDATA_SET(cx,ivar,o) \
cx->blk_loop.itervar = (SV**)(ivar);
#endif
-#define CxLABEL(c) (0 + (c)->blk_oldcop->cop_label)
+#define CxLABEL(c) (0 + CopLABEL((c)->blk_oldcop))
#define CxHASARGS(c) (((c)->cx_type & CXp_HASARGS) == CXp_HASARGS)
#define CxLVAL(c) (0 + (c)->blk_u16)