[Buildroot] [git commit] czmq: unbreak static linking

[Thomas Petazzoni]

Dear Peter Korsgaard,

On Tue, 12 May 2015 20:43:12 +0200, Peter Korsgaard wrote:
> commit: http://git.buildroot.net/buildroot/commit/?id=aa5254f1a2bc0ea3181d51990c18681b3071b9db
> branch: http://git.buildroot.net/buildroot/commit/?id=refs/heads/master
> 
> Fixes:
> http://autobuild.buildroot.net/results/faf/faf0bb00fccb1350afaef55f6cf14c11a5f5dc3c/
> http://autobuild.buildroot.net/results/8d2/8d279baa4c8bffbb01f897119092c7b736942df4/
> http://autobuild.buildroot.net/results/4d3/4d3dea604da9a5a1e7fe20548813f8de474ae33f/
> http://autobuild.buildroot.net/results/fd6/fd602617839817352763e51754553960b7f795ac/
> 
> And many more.
> 
> Zeromq uses C++, but czmq forgets to explicitly link with libstdc++
> (or use g++ to link), breaking static linking.
> 
> Signed-off-by: Peter Korsgaard <peter at korsgaard.com>
> ---
>  package/czmq/czmq.mk |    6 ++++++
>  1 files changed, 6 insertions(+), 0 deletions(-)
> 
> diff --git a/package/czmq/czmq.mk b/package/czmq/czmq.mk
> index d25bf01..789e700 100644
> --- a/package/czmq/czmq.mk
> +++ b/package/czmq/czmq.mk
> @@ -18,6 +18,12 @@ CZMQ_LICENSE_FILES = LICENSE
>  # host-python, so disable asciidoc entirely.
>  CZMQ_CONF_ENV = ac_cv_prog_czmq_have_asciidoc=no
>  
> +# zeromq uses C++, but czmq forgets to explicitly link with libstdc++
> +# (or use g++ to link), breaking static linking.
> +ifeq ($(BR2_STATIC_LIBS),y)
> +CZMQ_CONF_ENV += LIBS='-lstdc++'
> +endif

I continue to remain unhappy with such changes. There are two options
here:

 * Either using gcc to link with a C++ library is incorrect, and czmq
   should be fixed to use g++.

 * Or using gcc to link with a C++ library is correct, and in this
   case, libzmq.pc should be fixed to include -lstdc++ in Libs.private.

Best regards,

Thomas
-- 
Thomas Petazzoni, CTO, Free Electrons
Embedded Linux, Kernel and Android engineering
http://free-electrons.com