diff --git a/tests/DataRefTest.cpp b/tests/DataRefTest.cpp
index 6a42485..56c5d11 100644
--- a/tests/DataRefTest.cpp
+++ b/tests/DataRefTest.cpp
@@ -26,7 +26,7 @@
     REPORTER_ASSERT(reporter, !memcmp(ref->data(), data, len));
 }
 
-void TestDataRef(skiatest::Reporter* reporter) {
+static void TestDataRef(skiatest::Reporter* reporter) {
     const char* str = "We the people, in order to form a more perfect union.";
     const int N = 10;