Re: -falign-functions=16 for i386/amd64

[Ryota Ozaki <ozaki-r%netbsd.org@localhost>]

On Thu, Sep 1, 2016 at 10:14 PM, Adam <adam%netbsd.org@localhost> wrote:
>>>> http://www.netbsd.org/~ozaki-r/align-functions-16.diff
>>>>
>>>> The patch adds the option to sys/arch/amd64/conf/Makefile.amd64.
>>>> Is it a feasible place to add?
>>>
>>> There are two small issues I have with this patch:
>>> (1) I think it should be restricted to GCC with an appropiate comment of
>>> what this is a workaround for. Clang seems to behave a lot more sensible
>>> out of the box. If there are CPU models with a different base alignment
>>> and the user asked for one of them as optimisation target, it should be
>>> honored IMO.
>>> (2) This should not touch CFLAGS, but COPTS.
>>
>> Okay, I see. How about the following patch?
>> (nonaka@ helped improving Makefile options.)
>>
>> http://www.netbsd.org/~ozaki-r/align-functions-16.v2.diff
>>
>> Thanks,
>>  ozaki-r
>
> Have you tried compiling with clang? AFAIK, clang does not support -falign-functions (and warns about it).

The ACTIVE_CC trick ensures to add the option iff gcc is used.

  ozaki-r