diff --git a/Makefile b/Makefile
index ccfac69..5cd0bea 100644
--- a/Makefile
+++ b/Makefile
@@ -20,7 +20,7 @@ CFLAGS := $(CFLAGS) -Wall -Wextra -Wshadow -Wmissing-include-dirs -Wswitch-enum
 # The following is to supress a warning due to a protobuf that is fixed at v3.14.
 # It can be removed when or-tools is upgraded to v8.1+ (where the protobuf dependency is upgraded to v3.14).
 PROTOBUF_VERSION := $(shell $(OR_TOOLS_TOP)/bin/protoc --version | cut -d" " -f2)
-ifeq ($(shell dpkg --compare-versions $(PROTOBUF_VERSION) 'lt' '3.14' && echo true), true)
+ifeq ($(shell dpkg --compare-versions $(PROTOBUF_VERSION) 'lt' '3.19' && echo true), true)
 	CFLAGS := $(CFLAGS) -Wno-array-bounds
 endif
 
@@ -48,7 +48,7 @@ tsp_simple.o: tsp_simple.cc ortools_vrp.pb.h \
 
 tsp_simple: $(ROUTING_DEPS) tsp_simple.o ortools_vrp.pb.o ortools_result.pb.o $(OR_TOOLS_TOP)/lib/libortools.so
 	$(CXX) $(CFLAGS) -g tsp_simple.o ortools_vrp.pb.o ortools_result.pb.o $(OR_TOOLS_LD_FLAGS) \
-	-L $(OR_TOOLS_TOP)/lib -Wl,-rpath $(OR_TOOLS_TOP)/lib -lortools -lprotobuf \
+	-L $(OR_TOOLS_TOP)/lib -Wl,-rpath $(OR_TOOLS_TOP)/lib -lortools -L $(OR_TOOLS_TOP)/include/google -lprotobuf \
 	-o tsp_simple
 
 local_clean: