diff --git a/src/sksl/SkSLCPPCodeGenerator.h b/src/sksl/SkSLCPPCodeGenerator.h
index ea4d030..a93b885 100644
--- a/src/sksl/SkSLCPPCodeGenerator.h
+++ b/src/sksl/SkSLCPPCodeGenerator.h
@@ -41,6 +41,8 @@
 
     void writeIntLiteral(const IntLiteral& i) override;
 
+    void writeSwizzle(const Swizzle& swizzle) override;
+
     void writeVariableReference(const VariableReference& ref) override;
 
     String getSamplerHandle(const Variable& var);
@@ -87,6 +89,8 @@
     std::vector<String> fFormatArgs;
     std::set<int> fWrittenTransformedCoords;
     bool fNeedColorSpaceHelper = false;
+    // if true, we are writing a C++ expression instead of a GLSL expression
+    bool fCPPMode = false;
 
     typedef GLSLCodeGenerator INHERITED;
 };