[OE-core] why do we poison -Os?

[Khem Raj]

On 8/24/2011 3:52 AM, Phil Blundell wrote:
> On Wed, 2011-08-24 at 09:47 +0800, Xu, Dongxiao wrote:
>> My understanding is that, if GCC is not configured with the ability of code space optimization, target recipes will not have code size benefit even if adding "-Os" option.
>
> No, that's incorrect.  All that --enable-target-optspace does is change
> the definition of CFLAGS_FOR_TARGET, which causes the GCC support
> libraries (i.e. libgcc, libstdc++, etc) to be built with -Os rather than
> -O2.  It has no effect on the functionality of the compiler itself.
>

thats correct. this options is only for making gcc runtime to be built 
with Os. It does not make gcc to use -Os by default. The problem for ppc 
however is that if you built with Os then gcc depends upon functions 
from libgcc.a which needs libgcc.so to be a linker script stub rather 
than a symlink as it used to be but this has been fixed

> p.
>
>
>
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