[FIX #184] Cmake now explicitly links against libstdc++ and libm

src/core/CMakeLists.txt

@@ -44,7 +44,7 @@ COLLECT_COMPILE_FILES( "${CMAKE_CURRENT_SOURCE_DIR}" TARGET_CPP_FILES TARGET_H_F
 
 # Setup the target
 ADD_LIBRARY( ${LibName} SHARED ${TARGET_CPP_FILES} ${TARGET_H_FILES} ${OW_VERSION_HEADER} )
-TARGET_LINK_LIBRARIES( ${LibName} ${Boost_LIBRARIES} ${CMAKE_DL_LIBS} ${OPENGL_gl_LIBRARY} ${OPENSCENEGRAPH_LIBRARIES}
+TARGET_LINK_LIBRARIES( ${LibName} ${Boost_LIBRARIES} ${CMAKE_STANDARD_LIBRARIES} ${CMAKE_DL_LIBS} ${OPENGL_gl_LIBRARY} ${OPENSCENEGRAPH_LIBRARIES}
                      )
 
 # Tell CMake that someone creates this file for us. See doc of SETUP_VERSION_HEADER for details why this is needed.

tools/cmake/OpenWalnut.cmake

@@ -167,6 +167,10 @@ FUNCTION( BUILD_SYSTEM_COMPILER )
     SET( CMAKE_CXX_FLAGS_RELWITHDEBINFO "-g -DDEBUG -O2" CACHE STRING "" FORCE )
 ENDFUNCTION( BUILD_SYSTEM_COMPILER )
 
+# GCC 4.7 requires us to explicitly link against libstdc++ and libm. CMake offers a variable for this called "CMAKE_STANDARD_LIBRARIES".
+# Unfortunately, this variable is empty. We fill it here and hopefully this is fixed in the near future.
+LIST( APPEND CMAKE_STANDARD_LIBRARIES "stdc++" "m" )
+
 # Allow injection of other flags
 # NOTE: do not set these variables somewhere in cmake. They are intended to be used when calling CMake from the command line.
 # Utilize this to append build flags from external systems (like dpkg-buildflags).

tools/cmake/OpenWalnutUtils.cmake

@@ -150,7 +150,7 @@ FUNCTION( SETUP_TESTS _TEST_FILES _TEST_TARGET )
 
             # create the test-target
             CXXTEST_ADD_TEST( ${UnitTestName} "${UnitTestName}.cc" ${testfile} )
-            TARGET_LINK_LIBRARIES( ${UnitTestName} ${_TEST_TARGET} ${_DEPENDENCIES} )
+            TARGET_LINK_LIBRARIES( ${UnitTestName} ${_TEST_TARGET} ${CMAKE_STANDARD_LIBRARIES} ${_DEPENDENCIES} )
 
             # unfortunately, the tests search their fixtures relative to their working directory. So we add a preprocessor define containing the
             # path to the fixtures. This is quite ugly but I do not know how to ensure that the working directory of tests can be modified.
@@ -670,7 +670,7 @@ FUNCTION( SETUP_MODULE _MODULE_NAME _MODULE_SOURCE_DIR _MODULE_DEPENDENCIES _MOD
 
     # Setup the target
     ADD_LIBRARY( ${MODULE_NAME} SHARED ${TARGET_CPP_FILES} ${TARGET_H_FILES} )
-    TARGET_LINK_LIBRARIES( ${MODULE_NAME} ${OW_LIB_OPENWALNUT} ${Boost_LIBRARIES} ${OPENGL_gl_LIBRARY} ${OPENSCENEGRAPH_LIBRARIES} ${_MODULE_DEPENDENCIES} )
+    TARGET_LINK_LIBRARIES( ${MODULE_NAME} ${CMAKE_STANDARD_LIBRARIES} ${OW_LIB_OPENWALNUT} ${Boost_LIBRARIES} ${OPENGL_gl_LIBRARY} ${OPENSCENEGRAPH_LIBRARIES} ${_MODULE_DEPENDENCIES} )
 
     # Set the version of the library.
     SET_TARGET_PROPERTIES( ${MODULE_NAME} PROPERTIES