Re: [PATCH] build: use generic march on arm64 when using 'default' machine

[Luca Boccassi <bluca@debian.org>]

On Mon, 2019-01-07 at 12:24 +0000, Bruce Richardson wrote:
> On Mon, Dec 24, 2018 at 01:56:27PM +0100, Luca Boccassi wrote:
> > When building for generic distribution we need a stable baseline
> > architecture, or depending on the build worker the result will
> > vary.
> > 
> > Force the default flags if the user explicitly sets
> > marchine=default
> 
> typo: marchine
> 
> > at configuration time.
> > 
> > Fixes: b1d48c41189a ("build: support ARM with meson")
> > Cc: stable@dpdk.org
> > 
> > Signed-off-by: Luca Boccassi <bluca@debian.org>
> > ---
> >  config/arm/meson.build | 7 ++++++-
> >  1 file changed, 6 insertions(+), 1 deletion(-)
> > 
> > diff --git a/config/arm/meson.build b/config/arm/meson.build
> > index dae55d6b2..fa21a2fd2 100644
> > --- a/config/arm/meson.build
> > +++ b/config/arm/meson.build
> > @@ -6,6 +6,7 @@
> >  march_opt = '-march=@0@'.format(machine)
> >  
> >  arm_force_native_march = false
> > +arm_force_default_march = machine == 'default'
> 
> Do we need a new variable here? Given it only seems to be used once
> below,
> I think just having the boolean expression directly in the if
> statement is
> clearer. If you do keep the variable, suggest putting braces around
> the
> comparison, otherwise at first glance it looks like a chained
> assignment
> like you get in C e.g. x = y = 0;

Eheh it looks like I was a bit too hasty - I now remember that the main
reason I added a new variable is that the "machine" variable gets
overridden just before  the if branch, so the original value is lost. I
could refactor and rename, but that would be more intrusive so I had
opted to just do what was already done for the other "force" case.

-- 
Kind regards,
Luca Boccassi