Re: [BLACKBOX] Overflow checking (was: Type transfer)

From: [at]} <Chris>
Date: Tue, 18 Oct 2011 22:54:25 +1030

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>-----Original Message-----
>From: BlackBox [mailto:BLACKBOX{([at]})nowhere.xy
>Campbell, Robert (SELEX GALILEO, UK)
>Sent: Tuesday, 18 October 2011 10:09 PM
>To: BLACKBOX{([at]})nowhere.xy
>Subject: Re: [BLACKBOX] Overflow checking (was: Type transfer)
>
>Chris
>
>I might boast about my assembler prowess (I was inordinately
>proud of my 0-byte effort), but your 1-byte example is beyond me.
>
>Give us a clue: what is 0CEH?
>

Don't ask me - I cheated and peeked into the compiler to see how it does it.
If you start from the compiler options in DevCompiler:

  ...
  ELSIF s.char = "+" THEN INCL(opts, allchecks)

the trail will eventually lead you to the module DevCPV486 where you will
find:

  IF ovflchk THEN DevCPE.GenByte(0CEH) END;

I was then inspired by your zero byte example but went one better ;-)

Fortunately, Bernhard has now explained it to us *why* it works ...

Cheers,
Chris

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Received on Tue Oct 18 2011 - 14:24:25 UTC