exclude proto generated files from lint

Makefile

@@ -32,6 +32,10 @@ TOOL_SRCS := $(shell find tools -name "*.cpp")
 EXAMPLE_SRCS := $(shell find examples -name "*.cpp")
 # PROTO_SRCS are the protocol buffer definitions
 PROTO_SRCS := $(wildcard src/$(PROJECT)/proto/*.proto)
+# NONGEN_CXX_SRCS includes all source/header files except those generated by
+# proto.
+NONGEN_CXX_SRCS := $(shell find src/$(PROJECT) include/$(PROJECT) \
+	-regex ".*\.\(cpp\|hpp\|cu\|cuh\)")
 # PY$(PROJECT)_SRC is the python wrapper for $(PROJECT)
 PY$(PROJECT)_SRC := python/$(PROJECT)/py$(PROJECT).cpp
 PY$(PROJECT)_SO := python/$(PROJECT)/py$(PROJECT).so
@@ -111,9 +115,7 @@ linecount: clean
 	cloc --read-lang-def=$(PROJECT).cloc src/$(PROJECT)/
 
 lint:
-	./scripts/cpplint.py $(CXX_SRCS) $(HXX_SRCS) $(CU_SRCS) \
-		$(TEST_SRCS) $(TEST_HDRS) $(EXAMPLE_SRCS) \
-		$(PY$(PROJECT)_SRC) $(MAT$(PROJECT)_SRC)
+	./scripts/cpplint.py $(NONGEN_CXX_SRCS)
 
 test: init $(TEST_BINS)