diff --git a/clang-tools-extra/clang-tidy/misc/UnusedUsingDeclsCheck.h b/clang-tools-extra/clang-tidy/misc/UnusedUsingDeclsCheck.h
index 7bdaf12e8aece..e5f766dbac56b 100644
--- a/clang-tools-extra/clang-tidy/misc/UnusedUsingDeclsCheck.h
+++ b/clang-tools-extra/clang-tidy/misc/UnusedUsingDeclsCheck.h
@@ -51,7 +51,6 @@ class UnusedUsingDeclsCheck : public ClangTidyCheck {
   std::vector<UsingDeclContext> Contexts;
   llvm::SmallPtrSet<const Decl *, 32> UsingTargetDeclsCache;
 
-  StringRef RawStringHeaderFileExtensions;
   FileExtensionsSet HeaderFileExtensions;
 };