message: Avoid unnecessary use of virtual table
diff: @@ -939,7 +939,7 @@ static llvm::Value *lEmitPrePostIncDec(UnaryExpr::Op op, Expr *expr, SourcePos p
  type = type->GetReferenceTarget();
  lvalue = expr->GetValue(ctx);
  - Expr *deref = new RefDerefExpr(expr, expr->pos);
  + RefDerefExpr *deref = new RefDerefExpr(expr, expr->pos);
  rvalue = deref->GetValue(ctx);
  } else {
  lvalue = expr->GetLValue(ctx);
  