Re: [PATCH v5] scripts: use pkg-config to locate libcrypto

From: Masahiro Yamada
Date: Tue Jan 26 2021 - 11:07:23 EST


On Tue, Jan 26, 2021 at 5:01 PM Rolf Eike Beer <eb@xxxxxxxxx> wrote:
>
> Am Dienstag, 26. Januar 2021, 07:30:03 CET schrieb Masahiro Yamada:
> > On Tue, Jan 26, 2021 at 2:42 PM Rolf Eike Beer <eb@xxxxxxxxx> wrote:
> > > Am Mittwoch, 13. Januar 2021, 13:49:12 CET schrieb Rolf Eike Beer:
> > > > Otherwise build fails if the headers are not in the default location.
> > > > While
> > > > at it also ask pkg-config for the libs, with fallback to the existing
> > > > value.
> > >
> > > Can someone please take this through the kbuild-tree? Noone seems to be
> > > interested in picking this up so far.
>
> > Is 'PKG_CONFIG' necessary?
> >
> > I see many Makefiles hard-coding 'pkg-config'.
>
> Well, it depends ;)
>
> When people use pkgconf then this usually installs a pkg-config alias, too, so
> that would be no problem. The problem comes when other places in the kernel
> start copying that code over, and then hardcode pkg-config for stuff that
> needs a prefixed pkg-config because it is about target code.
>
> Given that I would prefer it this way, but YMMV. If it is that variable that
> blocks integrating I'll change it.
>
> Eike
> --
> Rolf Eike Beer, emlix GmbH, http://www.emlix.com
> Fon +49 551 30664-0, Fax +49 551 30664-11
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What I understood from commit a8a5cd8b472c is
the cross-compile prefix is needed
only for the target CC.


$(CC) -> $(CROSS_COMPILE)pkg-config (i.e. $(PKG_CONFIG))
$(HOSTCC) -> pkg-config


For cross-compiling, the prefixing makes sense
because $(CC) != $(HOSTCC)


In this case, scripts/extract-cert is a host tool
compiled by $(HOSTCC), so I do not see
a good reason to use $(PKG_CONFIG).


If somebody copy-pastes the code without understanding it,
that is their problem.

Let's do proper engineering. :-)



--
Best Regards
Masahiro Yamada