Makefile.base: cleanup non selected source object files

Makefile.base

@@ -113,9 +113,16 @@ include $(RIOTMAKE)/tools/fixdep.inc.mk
 $(BINDIR)/$(MODULE)/:
 	$(Q)mkdir -p $@
 
+OLD_OBJECTS = $(wildcard $(BINDIR)/$(MODULE)/*.o)
+OBJECTS_TO_REMOVE = $(filter-out $(OBJ),$(OLD_OBJECTS))
+
 $(MODULE).module compile-commands $(OBJ): | $(BINDIR)/$(MODULE)/
 
-$(MODULE).module: $(OBJ) | $(DIRS:%=ALL--%)
+$(MODULE).module: $(OBJ) $(if $(OBJECTS_TO_REMOVE),$(MODULE).cleanup) | $(DIRS:%=ALL--%)
+
+$(MODULE).cleanup:
+	$(Q)# cleanup non selected source files objects
+	$(Q)$(RM) $(OBJECTS_TO_REMOVE)
 
 CXXFLAGS = $(filter-out $(CXXUWFLAGS), $(CFLAGS)) $(CXXEXFLAGS)
 CCASFLAGS = $(filter-out $(CCASUWFLAGS), $(CFLAGS)) $(CCASEXFLAGS)