From: Thomas Demmer <demmer AT LSTM DOT Ruhr-UNI-Bochum DOT De>
Newsgroups: comp.os.msdos.djgpp
Subject: Re: Register variables with -O2
Date: Sat, 10 Jan 1998 18:14:18 +0100
Organization: Lehrstuhl fuer Stroemungsmechanik
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William A. Barath wrote:
> 
> On Thu, 8 Jan 1998, Geza Herman wrote:
> 
> |How can I tell the compiler which variables use as register and which
> |not when I use the option -O2?
> 
[...]
> 
> If your question is more along the lines of "How can I tell gcc to not
> registerize a variable for me" then I'd say "don't use the -O1 or -O2
> options"
That is a rather tough constraint sometimes. It is better to say 

volatile int foo;

to be sure foo won't end up as a register variable. 

[...]

-- 
Ciao
Tom

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* Thomas Demmer                                             *
* Lehrstuhl fuer Stroemungsmechanik                         *
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