Re: [Log4cplus-devel] Fixes for CMake build files.

[Václav Z. <vha...@gm...>]

On 13 September 2012 12:44, Chernyshev Vyacheslav wrote:
> 13.09.12, 9:55, Václav Zeman wrote:
>> I wonder what difficulties you have had with the Autotools build system
>> on MacOS X. I am keen on fixing those as well.
>
> There are some link problems when C++11 mode and Clang's libc++ is
> requested. Configure is done with something like that:
>     ../configure
>       --prefix=/opt/log4cplus_clang
>       --with-iconv
>       CC=/usr/bin/clang
>       CXX=/usr/bin/clang++
>       CXXFLAGS="-std=gnu++11 -stdlib=libc++ -O3 -march=native -DNDEBUG"
>       CFLAGS="-std=gnu99 -O3 -march=native -DNDEBUG"
>       LDFLAGS="-stdlib=libc++"
>
> Link failures appear after this line in output:
>     libtool: link: /usr/bin/clang++
>       -dynamiclib  -o .libs/liblog4cplus-1.1.4.dylib
>       <skipped object files list>
>       -liconv -O3 -march=native -O2
>       -install_name /opt/log4cplus_cmake/lib/liblog4cplus-1.1.4.dylib
>       -compatibility_version 5
>       -current_version 5.0
>       -Wl,-single_module
>
> I think that the problem is that CXXFLAGS and/or LDFLAGS are not
> properly passed to final link command. Without "-std=gnu++11
> -stdlib=libc++" a default c++ runtime library is linked to log4cplus and
> it results in undefined references.
This sounds like this might a be a Libtool or Automake problem. I am
afraid that I can hardly help with this. But I am willing to apply any
reasonable patches that fix this, if this is actually log4cplus
problem.

> As a side note, probably
> user-provided CXXFLAGS should be appended to the end of the list,
> otherwise default -O2 overrides user's decision.
I guess I should omit adding -O2 in case any other -O option is present there.

-- 
VZ