Since you use cygwin you didnt get these warnings:
act.other.c: In function 'do_spy'
act.other.c:1049: warning: array subscript has type 'char'
act.other.c:1049: warning: array subscript has type 'char'
act.other.c:1063: warning: array subscript has type 'char'
act.other.c:1063: warning: array subscript has type 'char'
act.other.c:1064: warning: array subscript has type 'char'
act.other.c:1071: warning: array subscript has type 'char'
line 1049 if (spy_type < 0 || !EXIT(ch, spy_type) || EXIT(ch, spy_type)->to_room == NOWHERE) {
1063 if (IS_SET(EXIT(ch, spy_type)->exit_info, EX_CLOSED) && EXIT(ch, spy_type)->keyword) {
1064 send_to_char(ch, "The %s is closed.\r\n", fname(EXIT(ch, spy_type)->keyword));
1071 char_to_room(ch, world[return_room].dir_option[spy_type]->to_room);