Re: [dpdk-dev] [dpdk-techboard] [PATCH 1/1] doc: add deprecation notice for CPU build flags

[Thomas Monjalon <thomas@monjalon.net>]

05/08/2020 17:07, Bruce Richardson:
> On Wed, Aug 05, 2020 at 04:57:42PM +0200, Thomas Monjalon wrote:
> > 05/08/2020 16:21, Bruce Richardson:
> > > The RTE_MACHINE_CPUFLAGS_* macros in DPDK build just duplicate info from
> > > the compiler macros, so we can remove them and just use the compiler
> > > versions directly.
> > > 
> > > Signed-off-by: Bruce Richardson <bruce.richardson@intel.com>
> > > ---
> > > --- a/doc/guides/rel_notes/deprecation.rst
> > > +++ b/doc/guides/rel_notes/deprecation.rst
> > > +* build macros: The macros defining RTE_MACHINE_CPUFLAG_* will be removed
> > > +  from the build. The information provided by these macros is available
> > > +  through standard compiler macros. For example, RTE_MACHINE_CPUFLAG_SSE3
> > > +  duplicates the compiler-provided macro __SSE3__.
> > 
> > I see 2 advantages of having alias:
> > 	- if 2 compilers differ, we can manage
> > 	- we can find all such macros with grep RTE_MACHINE_CPUFLAG
> >
> 
> Sure, if you think it's worthwhile keeping them, we can do so. It's just
> right now they seem to be largely a waste of space. For #2, I'm not sure
> when we would want to grep for them all, except possibly to remove them.
> :-)

For instance, in a lib, I grep where we have CPU specific code.

We probably need more opinions, I can change my mind.