error: 'W' already defined as constant
    at symbol-override.asm(6)
    and also:
    at symbol-override.asm(5)
error: 'X' already defined as constant
    at symbol-override.asm(10)
    and also:
    at symbol-override.asm(9)
error: 'Y' already defined as label
    at symbol-override.asm(14)
    and also:
    at symbol-override.asm(13)
Assembly aborted with 3 errors!