[Mesa-dev] [PATCH 1/3] meson: Define NDEBUG for non-debug-builds

[Eric Engestrom]

On Tuesday, 2018-07-17 10:26:49 -0400, robdclark at gmail.com wrote:
> On Tue, Jul 17, 2018 at 10:05 AM, Eric Engestrom
> <eric.engestrom at intel.com> wrote:
> > On Tuesday, 2018-07-17 09:01:46 -0400, mesa-dev-bounces at lists.freedesktop.org wrote:
> >> On Mon, Apr 16, 2018 at 5:19 PM, Dylan Baker <dylan at pnwbakers.com> wrote:
> >> > Quoting Jan Alexander Steffens (heftig) (2018-04-14 10:23:20)
> >> >> This is for parity with autotools. We were suddenly getting assertion
> >> >> failures after switching to meson, see [1].
> >> >>
> >> >> [1]: https://bugs.archlinux.org/task/58218
> >> >>
> >> >> Signed-off-by: Jan Alexander Steffens (heftig) <jan.steffens at gmail.com>
> >> >> ---
> >> >>  meson.build | 2 ++
> >> >>  1 file changed, 2 insertions(+)
> >> >>
> >> >> diff --git a/meson.build b/meson.build
> >> >> index a4dfa62255..931e0389e6 100644
> >> >> --- a/meson.build
> >> >> +++ b/meson.build
> >> >> @@ -705,6 +705,8 @@ endif
> >> >>  # Define DEBUG for debug builds only (debugoptimized is not included on this one)
> >> >>  if get_option('buildtype') == 'debug'
> >> >>    pre_args += '-DDEBUG'
> >> >> +else
> >> >> +  pre_args += '-DNDEBUG'
> >> >>  endif
> >> >>
> >> >>  if get_option('shader-cache')
> >> >> --
> >> >> 2.16.2
> >> >
> >> > NAK.
> >> >
> >> > meson has -Db_ndebug for controlling NDEBUG, which is done separately from
> >> > optimization levels, this is in our documentation as well as the meson
> >> > documentation. For builds without asserts, set b_ndebug=true.
> >> >
> >>
> >> Is it possible to make b_ndebug default to true for release builds?
> >> That would be far less surprising..
> >
> > Since 0.45 (we support 0.44.1 right now, so we would need to bump),
> > b_ndebug is no longer a boolean, but now accepts `if-release` as well.
> >
> > If that's the preferred solution, I can send this patch:
> > ----8<----
> > diff --git a/meson.build b/meson.build
> > index c62cdd0e395259ec984e..eb90f4cf9b265435fb19 100644
> > --- a/meson.build
> > +++ b/meson.build
> > @@ -25,8 +25,8 @@ project(
> >      [find_program('python', 'python2', 'python3'), 'bin/meson_get_version.py']
> >    ).stdout(),
> >    license : 'MIT',
> > -  meson_version : '>= 0.44.1',
> > -  default_options : ['buildtype=debugoptimized', 'c_std=c99', 'cpp_std=c++11']
> > +  meson_version : '>= 0.45',
> > +  default_options : ['buildtype=debugoptimized', 'b_ndebug=if-release', 'c_std=c99', 'cpp_std=c++11']
> >  )
> 
> is something like:
> 
> default_options : [(get_option('builttype') == 'debug') ?
> 'b_ndebug=false' : 'b_ndebug=true', ...]
> 
> something that is possible in meson?

I don't think this is possible in meson (I'll have a try later), but
fyi you can see the logic of `if-release` there:
https://github.com/mesonbuild/meson/blob/master/mesonbuild/compilers/compilers.py#L367

It's turning it on for `release`, not off for `debug`, which is subtly
different.

> 
> If not, I'd vote for b_ndebug=if-release.. even if we postpone it
> until we bump meson_version for other reasons.

It's not a very large bump (it's literally the next release), so it
might be ok to do now; otherwise, we can just leave this patch sit for
a few months.

> 
> 
> >  cc = meson.get_compiler('c')
> > ---->8----
> >
> > Dylan, thoughts?
> >
> >
> > PS:
> > Rob, your emails are still appearing as
> >   From: mesa-dev-bounces at lists.freedesktop.org
> > You might want to change this so people know it's you, and can reply
> > to you directly :)
> 
> daniels looked at this a while back.. I don't remember the details but
> it seems like this is happening on intel's mail server.  Not entirely
> sure why it picks on me, but also not sure I can do much about it.
> 
> /me shrugs

I didn't think to check, but you're right, it's only on the intel
server; my personal email got the right email headers.
Really weird how intel's server only butchers *your* emails too.

> 
> BR,
> -R
> 
> 
> >>
> >> BR,
> >> -R
> >> _______________________________________________
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> >> mesa-dev at lists.freedesktop.org
> >> https://lists.freedesktop.org/mailman/listinfo/mesa-dev