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

[Ingo Molnar]

* Krzysztof Halasa <khc@xxxxxxxxx> wrote:

> Ingo Molnar <mingo@xxxxxxx> 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.

	Ingo
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