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

[Chernyshev V. <ast...@ro...>]

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. As a side note, probably 
user-provided CXXFLAGS should be appended to the end of the list, 
otherwise default -O2 overrides user's decision.