add UBSAN to GCC (#378)

Author: nschimme

CMakeLists.txt

@@ -236,9 +236,13 @@ if(CMAKE_COMPILER_IS_GNUCXX)
     message(STATUS "Building with GCC (${CMAKE_CXX_COMPILER})")
     if(MMAPPER_IS_DEBUG)
         if(NOT WIN32)
-            message("-- Building with GCC address sanitizer")
+            message(STATUS "-- Building with GCC address sanitizer")
             add_compile_options(-fsanitize=address)
             add_link_options(-fsanitize=address)
+
+	    message(STATUS "Building with GCC undefined behavior sanitizer")
+            add_compile_options(-fsanitize=undefined)
+            add_link_options(-fsanitize=undefined)
         endif()
 
         add_compile_options(-Waddress)