turn off strict aliasing rules for gcc 4.4

git-svn-id: https://dng.biozentrum.unibas.ch/svn/openstructure/trunk@1914 5a81b35b-ba03-0410-adc8-b2c5c5119f08

CMakeLists.txt

@@ -156,6 +156,13 @@ endfunction()
 if (CMAKE_COMPILER_IS_GNUCXX)
   get_compiler_version(_GCC_VERSION)
   set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -Wall")
+  if (_GCC_VERSION MATCHES "44")
+    # gcc 4.4. is very strict about aliasing rules. the shared_count
+    # implementation that is used boost's shared_ptr violates these rules. To
+    # silence the warnings and prevent miscompiles, enable
+    #  -fno-strict-aliasing
+    set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -fno-strict-aliasing")
+  endif()
   if (APPLE AND NOT _GCC_VERSION MATCHES "42")
     set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -fvisibility=hidden")
   endif()