+CXXFLAGS+= -Wctor-dtor-privacy -Wdisabled-optimization -Winit-self -Wmissing-include-dirs -Wnoexcept -Wsign-promo -Wundef
+# suggests methods which already have such an attribute
+#CXXFLAGS+= -Wsuggest-attribute=pure -Wsuggest-attribute=const -Wsuggest-attribute=noreturn
+# gcc reports currently lots of them at the end of file - unknown reason
+CXXFLAGS+= -Wno-deprecated-declarations
+# sanitize options to be enabled for testing
+#CXXFLAGS+= -fsanitize=address -fsanitize=undefined -fno-sanitize=vptr