[Buildroot] [PATCH v2] pkg-infra: add <pkg>_CONFIG_FIXUP to fix *-config files

[Arnout Vandecappelle <arnout@mind.be>]

On 12/01/13 02:38, Stefan Fr?berg wrote:
> 11.1.2013 23:33, Arnout Vandecappelle kirjoitti:
>> On 10/01/13 20:52, Stefan Fr?berg wrote:
>>> This patch will add<pkg>_CONFIG_FIXUP variable to buildroot infra.
>>> It's purpose is to inform buildroot that the package in question
>>> contains some $(STAGING_DIR)/usr/bin/*-config files and that we
>>> want to automatically fix prefixes of such files.
[snip]
> I have a question that has been nagging in my head two days now:
>
> Let's suppose that command
>
> $(STAGING_DIR)/usr/bin/somepkg-config  --prefix gives the correct prefix
> $(STAGING_DIR)/usr  which is ok
>
> And $(STAGING_DIR)/usr/bin/somepkg-config --cflags gives empty (which is
> also fine)
>
> But $(STAGING_DIR)/usr/bin/somepkg-config --libs gives -L/usr/lib
>
> Isn't this horribly wrong ? I think it should give  -L$(STAGING_DIR)/usr/lib

  --libs should not give -L/usr/lib, that's for sure!

  I had a quick look at some *-config scripts, and I couldn't find any 
that does this. Maybe we should check all of them (51 in my allpkgbuild).

  A generic solution could be the following: put a script in 
$(HOST_DIR)/usr/bin (or some other directory) that hands the known 
arguments to pkg-config and redirects the rest back to the original 
*-config script. This makes patching of the *-config script unnecessary 
in most cases.

  Something to discuss (again) at the BR developer days?


> I noticed that some *-config files have just prefix (and maybe
> exec_prefix) but not any includedir or libdir defined inside them
> and just give -I/usr/include for --cflags and -L/usr/lib for --libs

  Even worse! Which one does that?

> Im beginning to suspect now that this is the very reason that my
> wireshark compilation borked, like you said Arnout, with that -L/usr/lib
> being added somehow to the final linking of wireshark binary  ....

  That could very well be...

> This or then that *.la file problem you mentioned.

  Yes, but the *.la file only puts it in there if it was instructed to 
search for that library in /usr/lib. So the path must have been given to 
it somewhere, either in config.status or hard-coded in some Makefile.in.

  Regards,
  Arnout

-- 
Arnout Vandecappelle                          arnout at mind be
Senior Embedded Software Architect            +32-16-286500
Essensium/Mind                                http://www.mind.be
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