Subject: Re: How to compare a kernel built with GCC 3.4.2 and GCC 4.0 (preliminary)
To: Vincent <10.50@free.fr>
From: Eric Haszlakiewicz <erh@jodi.nimenees.com>
List: tech-kern
Date: 11/09/2004 12:55:39
On Tue, Nov 09, 2004 at 06:38:54PM +0100, Vincent wrote:
> (Dien dobre ?)
	My family is polish, but you're approaching the limits of my
understanding of slavic languages. :)  (isn't is spelled "dzien dobre"? or
does that depend on the exact language?)

> It seems that gcc 4.0 removes a lot of functions to inline them. May be 
> routines that are called only once or twice ? they are inlined and 
> optimized ?
	from picking a couple of randon functions that disappeared, that
seems to be the case.  The sheer number of differences makes it a bit
difficult to easily tell what gcc is doing differently. (which I suppose
is to be expected)
	
> The other optimizations are minute, but the sum of them ends up being 
> significant.
	looks like at least some of the space savings is due to losing
strings that are intended to remain.  Notice that the ipfilter id
strings no longer show up in the "what" output.  Does the new kernel
retain things like the embedded kernel config (strings /netbsd | grep _CFG_)
or is that lost too?  If so, the size comparison isn't valid.

eric