commit https://github.com/vim/vim/commit/d0b5138ba4bccff8a744c99836041ef6322ed39a Author: Bram Moolenaar <Bram@vim.org> Date: Fri Nov 4 15:23:45 2016 +0100 patch 8.0.0056 Problem: When setting 'filetype' there is no check for a valid name. Solution: Only allow valid characters in 'filetype', 'syntax' and 'keymap'.

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}\")