Re: gcc -O2 bug

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#3679

From: Lawrence Kirby
Date: Sat, 10 Aug 1996 00:00

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In article <4uhp4i$pmu@pell.pell.chi.il.us> orc@pell.chi.il.us "Orc" writes:

...

>... but not smart enough to know that flag can be manipulated by a
>signal driven function while the loop is running.

It is smart enough to know that the language says it doesn't have to
worry about this. Instead it can concentrate on generatingh efficient
code.

>  Isn't optimization
>fun?  My first reaction, if I was still writing compilers, to assigning
>a variable's address to a global would be to treat the variable as a
>volatile from there on in, but I'm sure I could independently come up
>with pretty much the same reasons as the ANSI committee did for why
>that's not necessarily a good thing.

This simply comes down to knowing the language that you are programming
in. C is quite clear about what you are allowed to do in signal handlers.

-- 
-----------------------------------------
Lawrence Kirby | fred@genesis.demon.co.uk
Wilts, England | 70734.126@compuserve.com
-----------------------------------------

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From: Lawrence Kirby <fred@genesis.demon.co.uk>
Subject: Re: gcc -O2 bug
Date: 1996/08/10
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