-@DO_EXPORT RUNCC RUNLD CXXFLAGS LDLIBS PICLDFLAGS VERBOSE SOCKETENGINE CORELDFLAGS
-@DO_EXPORT SOURCEPATH BUILDPATH PURE_STATIC SPLIT_CC
+# Add the users CXXFLAGS to the base ones to allow them to override
+# things like -Wfatal-errors if they wish to.
+CORECXXFLAGS += $(CXXFLAGS)
+
+@DO_EXPORT RUNCC RUNLD CORECXXFLAGS LDLIBS PICLDFLAGS VERBOSE SOCKETENGINE CORELDFLAGS
+@DO_EXPORT SOURCEPATH BUILDPATH PURE_STATIC