Re: [patch 00/2] improve .text size on gcc 4.0 and newer compilers

Dave Jones
2005-12-29T08:03:22Z

On Thu, Dec 29, 2005 at 08:41:07AM +0100, Ingo Molnar wrote:
>
> * Krzysztof Halasa <khc@pm.waw.pl> wrote:
>
> > Ingo Molnar <mingo@elte.hu> writes:
> >
> > >> gcc version 4.0.2 20051109 (Red Hat 4.0.2-6)
> >
> > > another thing: i wanted to decrease the size of -Os
> > > (CONFIG_CC_OPTIMIZE_FOR_SIZE) kernels, which e.g. Fedora uses too (to
> > > keep the icache footprint down).
> >
> > Remember the above gcc miscompiles the x86-32 kernel with -Os:
> >
> > https://bugzilla.redhat.com/bugzilla/show_bug.cgi?id=173764
>
> i'm not sure what the point is. There was no sudden rush of -Os related
> bugs when Fedora switched to it for the kernel, and the 35% code-size
> savings were certainly worth it in terms of icache footprint. Yes, -Os
> is a major change for how the compiler works, and the kernel is a major
> piece of software.

The bug referenced is also fixed in gcc 4.1

Dave