[SRC] Linking openttd

Undefined symbols for architecture x86_64:

  "_deflate", referenced from:

      ZlibSaveFilter::Write(unsigned char*, unsigned long) in saveload.o

      ZlibSaveFilter::Finish() in saveload.o

  "_deflateEnd", referenced from:

      ZlibSaveFilter::~ZlibSaveFilter() in saveload.o

      ZlibSaveFilter::~ZlibSaveFilter() in saveload.o

  "_deflateInit_", referenced from:

      SaveFilter* CreateSaveFilter<ZlibSaveFilter>(SaveFilter*, unsigned char) in saveload.o

  "_gzclose", referenced from:

      ClientNetworkContentSocketHandler::AfterDownload() in network_content.o

  "_gzdopen", referenced from:

      ClientNetworkContentSocketHandler::AfterDownload() in network_content.o

  "_gzerror", referenced from:

      ClientNetworkContentSocketHandler::AfterDownload() in network_content.o

  "_gzread", referenced from:

      ClientNetworkContentSocketHandler::AfterDownload() in network_content.o

  "_inflate", referenced from:

      ZlibLoadFilter::Read(unsigned char*, unsigned long) in saveload.o

      TextfileWindow::LoadTextfile(char const*, Subdirectory) in textfile_gui.o

  "_inflateEnd", referenced from:

      ZlibLoadFilter::~ZlibLoadFilter() in saveload.o

      ZlibLoadFilter::~ZlibLoadFilter() in saveload.o

      TextfileWindow::LoadTextfile(char const*, Subdirectory) in textfile_gui.o

  "_inflateInit2_", referenced from:

      TextfileWindow::LoadTextfile(char const*, Subdirectory) in textfile_gui.o

  "_inflateInit_", referenced from:

      LoadFilter* CreateLoadFilter<ZlibLoadFilter>(LoadFilter*) in saveload.o

  "_zlibVersion", referenced from:

      CrashLog::LogLibraries(char*, char const*) const in crashlog.o

      CrashLog::FillCrashLog(char*, char const*) const in crashlog.o

ld: symbol(s) not found for architecture x86_64

clang: error: linker command failed with exit code 1 (use -v to see invocation)

make[1]: *** [openttd] Error 1

make: *** [all] Error 1