Pass-dependent construction encountered

The statement may not behave as you expect, due to the one-pass nature of
Turbo Assembler. For example,

   IF1 
            ;Happens on assembly pass 
   ENDIF 
   IF2 
            ;Happens on listing pass 
   ENDIF 

Most constructs that generate this error can be re-coded to avoid it,
often by removing forward references. Also, use of /m multipass switch can
enable TASM to resolve these kinds of constructs.