diff --git a/tests/RectangleTextureTest.cpp b/tests/RectangleTextureTest.cpp
index ac81e6d..21a9e19 100644
--- a/tests/RectangleTextureTest.cpp
+++ b/tests/RectangleTextureTest.cpp
@@ -23,7 +23,10 @@
 // skbug.com/5932
 static void test_basic_draw_as_src(skiatest::Reporter* reporter, GrContext* context,
                                    sk_sp<GrTextureProxy> rectProxy, uint32_t expectedPixelValues[]) {
+    GrBackendFormat format = rectProxy->backendFormat().makeTexture2D();
+    SkASSERT(format.isValid());
     sk_sp<GrRenderTargetContext> rtContext(context->contextPriv().makeDeferredRenderTargetContext(
+                                                     format,
                                                      SkBackingFit::kExact, rectProxy->width(),
                                                      rectProxy->height(), rectProxy->config(),
                                                      nullptr));