commit https://github.com/vim/vim/commit/f1f60f859cdbb2638b3662ccf7b1d179865fe7dc Author: Bram Moolenaar <Bram@vim.org> Date: Sat Jan 16 15:40:53 2016 +0100 patch 7.4.1102 Problem: Debugger has no stack backtrace support. Solution: Add "backtrace", "frame", "up" and "down" commands. (Alberto Fanjul, closes https://github.com/vim/vim/issues/433)

TYPEMAP
VIWIN	T_VIOBJNOMUNGE
VIBUF	T_VIOBJNOMUNGE

INPUT
T_VIOBJNOMUNGE
	if (sv_isa($arg, \"${ntype}\")) {
	    IV tmp = SvIV((SV*)SvRV($arg));
	    $var = INT2PTR($type, tmp);
	    if (!tmp)
		croak(\"$ntype no longer exists\");
	}
	else
	    croak(\"$var is not of type ${ntype}\")