[PATCH 2/2] tools: kwboot: use pkg-config to get -ltinfo

[Pali Rohár]

On Tuesday 19 July 2022 21:11:21 Heiko Thiery wrote:
> Hi,
> 
> Am Di., 19. Juli 2022 um 20:52 Uhr schrieb Pali Rohár <pali at kernel.org>:
> >
> > On Tuesday 19 July 2022 20:38:39 Heiko Thiery wrote:
> > > Instead of hardcoding -ltinfo as the flags needed to build
> > > kwboot, use pkg-config when available.
> >
> > Interesting, I did not know that there is pc file also for tinfo.
> > Anyway when using it, there should be also HOSTCFLAGS_kwboot definition
> > from pkg-config.
> 
> Just checked the cflags for tinfo.
> 
> # pkg-config --cflags tinfo
> -D_DEFAULT_SOURCE -D_XOPEN_SOURCE=600

I think these two flags are harmless...

> Can we also add that to kwboot?

... but now it reminds me that we have issues with tinfo header files
which are in direct conflict with linux uapi termbits header files.
And so kwboot.c does not include any tinfo header file.

Therefore tinfo cflags are not used at all.

So I would rather stick with not importing --cflags to prevent possible
future incompatibility (in case into tinfo cflags in future would be
added something which conflict with linux uapi header files). We do not
need them at all.

> >
> > > We gracefully fallback on the previous behavior of hardcoding -ltinfo
> > > if pkg-config is not available or fails with an error.
> > >
> > > Signed-off-by: Heiko Thiery <heiko.thiery at gmail.com>
> > > ---
> > >  tools/Makefile | 4 +++-
> > >  1 file changed, 3 insertions(+), 1 deletion(-)
> > >
> > > diff --git a/tools/Makefile b/tools/Makefile
> > > index 9f6b282ad8..45195a8ce7 100644
> > > --- a/tools/Makefile
> > > +++ b/tools/Makefile
> > > @@ -198,7 +198,9 @@ hostprogs-$(CONFIG_EXYNOS5420) += mkexynosspl
> > >  HOSTCFLAGS_mkexynosspl.o := -pedantic
> > >
> > >  HOSTCFLAGS_kwboot.o += -pthread
> > > -HOSTLDLIBS_kwboot += -pthread -ltinfo
> > > +HOSTLDLIBS_kwboot += -pthread
> > > +HOSTLDLIBS_kwboot += \
> > > +     $(shell pkg-config --libs tinfo 2> /dev/null || echo "-ltinfo")
> > >
> > >  ifdtool-objs := $(LIBFDT_OBJS) ifdtool.o
> > >  hostprogs-$(CONFIG_X86) += ifdtool
> > > --
> > > 2.30.2
> > >
> 
> --
> Heiko