Re: [v4l-utils PATCH 1/1] Fix static linking of v4l2-compliance and v4l2-ctl

[Sakari Ailus <sakari.ailus@linux.intel.com>]

Hi Mauro,

On 09/19/16 14:22, Mauro Carvalho Chehab wrote:
> Em Mon, 19 Sep 2016 13:50:25 +0300
> Sakari Ailus <sakari.ailus@linux.intel.com> escreveu:
> 
>> v4l2-compliance and v4l2-ctl depend on librt and libpthread. The symbols
>> are found by the linker only if these libraries are specified after the
>> objects that depend on them.
>>
>> As LDFLAGS variable end up expanded on libtool command line before LDADD,
>> move the libraries to LDADD after local objects. -lpthread is added as on
>> some systems librt depends on libpthread. This is the case on Ubuntu 16.04
>> for instance.
>>
>> After this patch, creating a static build using the command
>>
>> LDFLAGS="--static -static" ./configure --disable-shared --enable-static
> 
> It sounds weird to use LDFLAGS="--static -static" here, as the
> configure options are already asking for static.
> 
> IMHO, the right way would be to change configure.ac to add those LDFLAGS
> when --disable-shared is used.

That's one option, but then shared libraries won't be built at all. I'm
not sure what would be the use cases for that, though: static linking
isn't very commonly needed except when you need to run the binaries
elsewhere (for whatever reason) where you don't have the libraries you
linked against available.

That's still a separate issue from what this patch fixes.

Ideally it should be possible to link the binaries statically while
still building shared libraries: both are built by default right now,
yet shared libraries are always used for linking unless you disable
shared libraries. Most of the time this makes sense but not always.

I'm sending a separate patch to fix that by adding
--with-static-binaries option.

-- 
Sakari Ailus
sakari.ailus@linux.intel.com