Re: [2.6 patch] re-add -ffreestanding

[Adrian Bunk <bunk@stusta.de>]

On Tue, Aug 22, 2006 at 12:37:13PM +0200, Andi Kleen wrote:
> On Mon, 21 Aug 2006 23:37:31 -0400
> Kyle Moffett <mrmacman_g4@mac.com> wrote:
> 
> > On Aug 21, 2006, at 19:13:20, Andi Kleen wrote:
> > >> What's the problem with adding -ffreestanding and stating  
> > >> explicitely which functions we want to be handled be builtins, and  
> > >> which functions we don't want to be handled by builtins?
> > >
> > > Take a look at lib/string.c and think about it a bit.
> > 
> > So why can't lib/string.c explicitly say __builtin_foo() instead of  
> > foo() where we mean the former? 
> 
> Because gcc when using builtins sometimes decides to call the 
> out of line version (usually when it can't figure out the alignment
> and generic alignment code would be too large to inline). And it will
> always call str/memfoo not __builtin_str/memfoo

IOW, we might in some cases require an out-of-line version of the 
function?

I don't see in this case any problem created by using -ffreestanding and 
the #define's.

> -Andi

cu
Adrian

-- 

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