diff --git a/clang/lib/AST/Interp/InterpBuiltin.cpp b/clang/lib/AST/Interp/InterpBuiltin.cpp
index de3d72169432f..6550a07650c88 100644
--- a/clang/lib/AST/Interp/InterpBuiltin.cpp
+++ b/clang/lib/AST/Interp/InterpBuiltin.cpp
@@ -1237,7 +1237,7 @@ bool InterpretOffsetOf(InterpState &S, CodePtr OpPC, const OffsetOfExpr *E,
       const RecordType *RT = CurrentType->getAs<RecordType>();
       if (!RT)
         return false;
-      RecordDecl *RD = RT->getDecl();
+      const RecordDecl *RD = RT->getDecl();
       if (RD->isInvalidDecl())
         return false;
       const ASTRecordLayout &RL = S.getCtx().getASTRecordLayout(RD);