Re: const and valarray reference

From: Victor Bazarov (v.Abazarov_at_attAbi.com)
Date: 10/23/03 

Date: Thu, 23 Oct 2003 21:55:32 GMT

"Jim West" <eggplantparts@yahoo.com> wrote...
>
> The following compiles with g++ 3.3.2, but fails with Intel icc 7.1 with
> the error:
>
> asdf.cc(6): error: expression must be an lvalue or a function designator
> f1(&arr[0]);
>
> Is this undefined behavior, or have I found a problem with one compiler?
>
> Code sample is:
>
> void f1(const double *);
>
> void f2(const std::valarray<double> &arr) {
> f1(&arr[0]);
> }

Constant std::valarray's operator[] returns an rvalue. You
cannot take an address of it. What are you trying to accomplish?
Perhaps changing f1 to accept a double const & would help:

    void f1(double const&);
    void f2(std::valarray<double> const& arr) {
        f1(arr[0]);
    }

?

Victor

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