diff --git a/.clang-tidy b/.clang-tidy
index 32a9cbe87..5873f4a9d 100644
--- a/.clang-tidy
+++ b/.clang-tidy
@@ -35,6 +35,8 @@ CheckOptions:
     value:           aNy_CasE
   - key:             readability-identifier-naming.MemberCase
     value:           aNy_CasE
+  - key:             readability-identifier-naming.ClassMemberPrefix
+    value:           'm_'
   - key:             readability-identifier-naming.ParameterCase
     value:           aNy_CasE
   - key:             readability-identifier-naming.UnionCase
diff --git a/include/clad/Differentiator/VectorForwardModeVisitor.h b/include/clad/Differentiator/VectorForwardModeVisitor.h
index a5a21d13a..fd1dfec17 100644
--- a/include/clad/Differentiator/VectorForwardModeVisitor.h
+++ b/include/clad/Differentiator/VectorForwardModeVisitor.h
@@ -22,6 +22,10 @@ class VectorForwardModeVisitor : public BaseForwardModeVisitor {
   /// the derivatives.
   clang::Expr* m_IndVarCountExpr;
 
+  clang::Expr* test;
+  clang::Expr* m_test;
+  clang::Expr* M_test;
+
 public:
   VectorForwardModeVisitor(DerivativeBuilder& builder);
   ~VectorForwardModeVisitor();