[oe] [meta-oe][PATCH] libwebsockets: Fix the build with -Os

[Khem Raj]

On Thu, Aug 29, 2019 at 12:14 PM Adrian Bunk <bunk at stusta.de> wrote:
>
> On Thu, Aug 29, 2019 at 11:46:55AM -0700, Khem Raj wrote:
> > On Thu, Aug 29, 2019 at 3:39 AM Adrian Bunk <bunk at stusta.de> wrote:
> > >
> > > lib/event-libs/libuv/libuv.c: In function 'elops_destroy_context1_uv':
> > > lib/event-libs/libuv/libuv.c:519:7: error: 'm' may be used uninitialized in this function [-Werror=maybe-uninitialized]
> > >     if (m)
> > >        ^
> > >
> > > Signed-off-by: Adrian Bunk <bunk at stusta.de>
> > > ---
> > >  .../recipes-connectivity/libwebsockets/libwebsockets_3.1.0.bb   | 2 ++
> > >  1 file changed, 2 insertions(+)
> > >
> > > diff --git a/meta-oe/recipes-connectivity/libwebsockets/libwebsockets_3.1.0.bb b/meta-oe/recipes-connectivity/libwebsockets/libwebsockets_3.1.0.bb
> > > index 50620d99e..fcabeb902 100644
> > > --- a/meta-oe/recipes-connectivity/libwebsockets/libwebsockets_3.1.0.bb
> > > +++ b/meta-oe/recipes-connectivity/libwebsockets/libwebsockets_3.1.0.bb
> > > @@ -28,3 +28,5 @@ EXTRA_OECMAKE += " \
> > >  PACKAGES =+ "${PN}-testapps"
> > >
> > >  FILES_${PN}-testapps += "${datadir}/libwebsockets-test-server/*"
> > > +
> > > +CFLAGS_append = " -Wno-error"
> >
> > is it possible to fix the underlying problem? since Os is not default
> > it definitely could be a bug in upstream but
> > by disabling warnings for all kind of builds we are  painting with broad brush
>
> The underlying problem is that some gcc warnings are not reliable with -Os,
> there are bugs open in the gcc bugzilla for that.
>
I am aware of that for maybe-* warnings heuristics may go wrong, but
then its better to just disable that
one warning from being treated as error if thats possible to add
easily something like
-Wno-error=maybe-uninitialized could do it.

> cu
> Adrian
>
> --
>
>        "Is there not promise of rain?" Ling Tan asked suddenly out
>         of the darkness. There had been need of rain for many days.
>        "Only a promise," Lao Er said.
>                                        Pearl S. Buck - Dragon Seed
>