diff --git a/backends/protobuf/Makefile.inc b/backends/protobuf/Makefile.inc
index 834cad42c..9cac9dcaa 100644
--- a/backends/protobuf/Makefile.inc
+++ b/backends/protobuf/Makefile.inc
@@ -3,6 +3,8 @@ ifeq ($(ENABLE_PROTOBUF),1)
 backends/protobuf/yosys.pb.cc backends/protobuf/yosys.pb.h: misc/yosys.proto
 	$(Q) cd misc && protoc --cpp_out "../backends/protobuf" yosys.proto
 
+backends/protobuf/protobuf.cc: backends/protobuf/yosys.pb.h
+
 OBJS += backends/protobuf/protobuf.o backends/protobuf/yosys.pb.o
 
 endif