diff --git a/core/fpdfapi/render/cpdf_imagerenderer.cpp b/core/fpdfapi/render/cpdf_imagerenderer.cpp
index b4568ae..bc650ed 100644
--- a/core/fpdfapi/render/cpdf_imagerenderer.cpp
+++ b/core/fpdfapi/render/cpdf_imagerenderer.cpp
@@ -543,6 +543,8 @@
     case Mode::kTransform:
       return ContinueTransform(pPause);
   }
+  NOTREACHED();
+  return false;
 }
 
 bool CPDF_ImageRenderer::ContinueDefault(PauseIndicatorIface* pPause) {