Renamed make variables for protoc presence and version checking.
diff --git a/Makefile b/Makefile
index 8cd7160..4d18c4a 100644
--- a/Makefile
+++ b/Makefile
@@ -348,8 +348,8 @@
 ZLIB_CHECK_CMD = $(CC) $(CFLAGS) $(CPPFLAGS) -o $(TMPOUT) test/build/zlib.c -lz $(LDFLAGS)
 PERFTOOLS_CHECK_CMD = $(CC) $(CFLAGS) $(CPPFLAGS) -o $(TMPOUT) test/build/perftools.c -lprofiler $(LDFLAGS)
 PROTOBUF_CHECK_CMD = $(CXX) $(CXXFLAGS) $(CPPFLAGS) -o $(TMPOUT) test/build/protobuf.cc -lprotobuf $(LDFLAGS)
-PROTOC_CMD = which protoc > /dev/null
-PROTOC_CHECK_CMD = protoc --version | grep -q libprotoc.3
+PROTOC_CHECK_CMD = which protoc > /dev/null
+PROTOC_CHECK_VERSION_CMD = protoc --version | grep -q libprotoc.3
 
 ifeq ($(OPENSSL_REQUIRES_DL),true)
 OPENSSL_ALPN_CHECK_CMD += -ldl
@@ -375,9 +375,9 @@
 HAS_SYSTEM_PROTOBUF = false
 endif
 
-HAS_PROTOC = $(shell $(PROTOC_CMD) 2> /dev/null && echo true || echo false)
+HAS_PROTOC = $(shell $(PROTOC_CHECK_CMD) 2> /dev/null && echo true || echo false)
 ifeq ($(HAS_PROTOC),true)
-HAS_VALID_PROTOC = $(shell $(PROTOC_CHECK_CMD) 2> /dev/null && echo true || echo false)
+HAS_VALID_PROTOC = $(shell $(PROTOC_CHECK_VERSION_CMD) 2> /dev/null && echo true || echo false)
 else
 HAS_VALID_PROTOC = false
 endif
@@ -1212,7 +1212,7 @@
 	$(ZLIB_CHECK_CMD) || true
 	$(PERFTOOLS_CHECK_CMD) || true
 	$(PROTOBUF_CHECK_CMD) || true
-	$(PROTOC_CHECK_CMD) || true
+	$(PROTOC_CHECK_VERSION_CMD) || true
 
 $(LIBDIR)/$(CONFIG)/zlib/libz.a:
 	$(E) "[MAKE]    Building zlib"
diff --git a/templates/Makefile.template b/templates/Makefile.template
index 9ca55f4..21c2945 100644
--- a/templates/Makefile.template
+++ b/templates/Makefile.template
@@ -362,8 +362,8 @@
 ZLIB_CHECK_CMD = $(CC) $(CFLAGS) $(CPPFLAGS) -o $(TMPOUT) test/build/zlib.c -lz $(LDFLAGS)
 PERFTOOLS_CHECK_CMD = $(CC) $(CFLAGS) $(CPPFLAGS) -o $(TMPOUT) test/build/perftools.c -lprofiler $(LDFLAGS)
 PROTOBUF_CHECK_CMD = $(CXX) $(CXXFLAGS) $(CPPFLAGS) -o $(TMPOUT) test/build/protobuf.cc -lprotobuf $(LDFLAGS)
-PROTOC_CMD = which protoc > /dev/null
-PROTOC_CHECK_CMD = protoc --version | grep -q libprotoc.3
+PROTOC_CHECK_CMD = which protoc > /dev/null
+PROTOC_CHECK_VERSION_CMD = protoc --version | grep -q libprotoc.3
 
 ifeq ($(OPENSSL_REQUIRES_DL),true)
 OPENSSL_ALPN_CHECK_CMD += -ldl
@@ -389,9 +389,9 @@
 HAS_SYSTEM_PROTOBUF = false
 endif
 
-HAS_PROTOC = $(shell $(PROTOC_CMD) 2> /dev/null && echo true || echo false)
+HAS_PROTOC = $(shell $(PROTOC_CHECK_CMD) 2> /dev/null && echo true || echo false)
 ifeq ($(HAS_PROTOC),true)
-HAS_VALID_PROTOC = $(shell $(PROTOC_CHECK_CMD) 2> /dev/null && echo true || echo false)
+HAS_VALID_PROTOC = $(shell $(PROTOC_CHECK_VERSION_CMD) 2> /dev/null && echo true || echo false)
 else
 HAS_VALID_PROTOC = false
 endif
@@ -587,7 +587,7 @@
 	$(ZLIB_CHECK_CMD) || true
 	$(PERFTOOLS_CHECK_CMD) || true
 	$(PROTOBUF_CHECK_CMD) || true
-	$(PROTOC_CHECK_CMD) || true
+	$(PROTOC_CHECK_VERSION_CMD) || true
 
 $(LIBDIR)/$(CONFIG)/zlib/libz.a:
 	$(E) "[MAKE]    Building zlib"