Date: Thu, 8 Jan 1998 17:07:46 +0200 (IST)
From: Eli Zaretskii <eliz AT is DOT elta DOT co DOT il>
To: Geza Herman <geza AT inf DOT bme DOT hu>
cc: djgpp AT delorie DOT com
Subject: Re: Register variables with -O2
In-Reply-To: <Pine.GSO.3.95.980108130328.17326A-100000@kempelen.inf.bme.hu>
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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?

In general, you can't, unless you write inline assembly.  The `register' 
qualifier is just a suggestion, the compiler can ignore it at will.

I really don't think you need to be worried about this, though.  The GCC 
optimizer usually does a better job in allocating registers that 
programmers do.  Trust it.