diff --git a/Makefile b/Makefile
index 2db2a1f..c97de5e 100644
--- a/Makefile
+++ b/Makefile
@@ -45,11 +45,11 @@ src/decomp/mario/geo.inc.c: ./import-mario-geo.py
 	./import-mario-geo.py
 
 $(BUILD_DIR)/%.o: %.c $(IMPORTED)
-	@$(CC) $(CFLAGS) -MM -MP -MT $@ -MF $(BUILD_DIR)/$*.d $<
+	@$(CC) $(CFLAGS) -I src/decomp/include -MM -MP -MT $@ -MF $(BUILD_DIR)/$*.d $<
 	$(CC) -c $(CFLAGS) -I src/decomp/include -o $@ $<
 
 $(BUILD_DIR)/%.o: %.cpp $(IMPORTED)
-	@$(CXX) $(CFLAGS) -MM -MP -MT $@ -MF $(BUILD_DIR)/$*.d $<
+	@$(CXX) $(CFLAGS) -I src/decomp/include -MM -MP -MT $@ -MF $(BUILD_DIR)/$*.d $<
 	$(CXX) -c $(CFLAGS) -I src/decomp/include -o $@ $<
 
 $(LIB_FILE): $(O_FILES)