Piotr Caban (@piotr) commented about dlls/msvcrt/undname.c:
if (!(n1 = get_number(sym))) return FALSE; num = atoi(n1);
if (ct->left && ct->left[0] == ' ' && !xdt.left)
ct->left++;
ct->left = str_printf(sym, " (%s%s", xdt.left, ct->left);
ct->left = str_printf(sym, " (%s%s", xdt.left, ct->left + (ct->left && xdt.left ? 0 : 1));
This looks broken in ct->left == NULL case.