[Buildroot] [PATCH 1/1] package/python-argon2-cffi: use -msse2 only when supported

[James Hilliard <james.hilliard1@gmail.com>]

On Wed, Apr 15, 2020 at 2:22 PM James Hilliard
<james.hilliard1@gmail.com> wrote:
>
> On Wed, Apr 15, 2020 at 2:20 PM James Hilliard
> <james.hilliard1@gmail.com> wrote:
> >
> > On Wed, Apr 15, 2020 at 2:10 PM Thomas Petazzoni
> > <thomas.petazzoni@bootlin.com> wrote:
> > >
> > > Hello Asaf,
> > >
> > > On Tue, 14 Apr 2020 13:26:21 +0300
> > > Asaf Kahlon <asafka7@gmail.com> wrote:
> > >
> > > > The package adds the '-msse2' flag according to the result of the
> > > > pythonic "platform.machine()" statement, which runs on the host
> > > > and doesn't necessarily reflects the existence of this flag on
> > > > the target compiler.
> > > > Hence, we'll set the 'optimzed' variable in setup.py only when
> > >
> > > optimzed -> optimized
> > >
> > > > +define PYTHON_ARGON2_CFFI_SET_OPTIMZED_FLAG
> > >
> > > optimized
> > >
> > > > +        $(SED) 's;^\(optimized = *\)\(.*\);\1$(if $(BR2_X86_CPU_HAS_SSE2),True,False);' $(@D)/setup.py
> > > > +endef
> > > > +
> > > > +PYTHON_ARGON2_CFFI_POST_PATCH_HOOKS += PYTHON_ARGON2_CFFI_SET_OPTIMZED_FLAG
> > >
> > > optimized
> > >
> > > But can't we do better here ? Check if the compiler supports the -msse2
> > > flag ? See
> > > https://github.com/pybind/python_example/blob/master/setup.py#L38 for
> > > an example on how to do that.
> > Ah, that looks better, I had submitted
> > https://github.com/hynek/argon2-cffi/pull/59
> > to avoid having to patch setup.py, I'll see if I can get that working.
> Oh, just noticed we'll probably still need both since argon2-cffi
> supports python2.
Nevermind, that comment appears to be totally inaccurate as Python
3.6's CCompiler
does not actually have a has_flag method at all, however we can just include the
function which seems to work. I've updated my pull request with a reworked
version of has_flag which seems to work.
> > >
> > > Thanks!
> > >
> > > Thomas
> > > --
> > > Thomas Petazzoni, CTO, Bootlin
> > > Embedded Linux and Kernel engineering
> > > https://bootlin.com