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Re: [PATCH] gas: Add --with-optimization=OPTION

>>> On 27.02.18 at 15:19, <hjl.tools@gmail.com> wrote:
> On Tue, Feb 27, 2018 at 6:06 AM, Jan Beulich <JBeulich@suse.com> wrote:
>>>>> On 27.02.18 at 14:44, <hjl.tools@gmail.com> wrote:
>>> I'd like to change x86 assembler to turn -O2 on by default without
>>> any configure-time option.  But if such encoding changes may break
>>> existing code, I don't want to risk it to even support -On at all.
>>
>> I don't understand this: As we've seen, Linux would very much like
>> to enable optimizations. Yet that doesn't mean everyone wants it,
>> nor that it should be the default.
>>
> 
> We never guarantee that instruction encoding is fixed as there is
> more than one way to encode an instruction.  Is there a way find
> out who don't want it?

The only way I can think of is to wait for bug reports. But that's
not something I would suggest we do.

Jan
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