RUBY_VM_END_CONTROL_FRAME  905 eval.c             rb_control_frame_t *end_cfp = RUBY_VM_END_CONTROL_FRAME(th);
RUBY_VM_END_CONTROL_FRAME  555 vm_core.h        (!RUBY_VM_VALID_CONTROL_FRAME_P((cfp), RUBY_VM_END_CONTROL_FRAME(th)))