Re: RS/6000 Optimizer breaks code -- suggestions?

[Commentary deleted]
>But, having said all that, I actually agree with your assertion that the
>implentation is not "sane", but only because the situations where it's
>safe to rearrange a union are probably rare, and more often than not will
>occur because the programmer was trying to use the union to fake up a
>type cast. So the optimization is more likely to hurt than to help.
>
>[Can someone run the original code through the RS/6000 compiler, look at
>the object code, and report whether the compiler is in fact doing something
>strange? IBM is usually pretty good at reading standards. -John]


The union in this case was in fact used as a type cast of sorts; a method
to prevent a short from overflowing. Bad style and not portable begins to
sum up this approach. However...


This has been submitted to IBM tech and verified as a real bug. If anyone
would like a 'clean' copy of the code in question, please mail requests to
banshee@ucscb.UCSC.EDU.
--

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