Segment and external symbols used in relocatable expressions

I know that for Keil assembler, "Segment and external symbols are not allowed in simple relocatable expressions".

I just want to ask is there any tricks or "non-simple" way that can do the same effect. Thx..!!

(for example,

     EXTRN    code (Start)
     Reset    equ   Start ;<--Not allowed
 

how can I do the same effect? )

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