Re: dynamic array and constructors

From:
James Kanze <james.kanze@gmail.com>
Newsgroups:
comp.lang.c++
Date:
Fri, 31 Oct 2008 05:05:52 -0700 (PDT)
Message-ID:
<fe36233d-1504-439d-a784-d321463d16f4@t39g2000prh.googlegroups.com>
On Oct 31, 9:42 am, Urs Thuermann <u...@janus.isnogud.escape.de>
wrote:

I have some old code I've written several years ago that
doesn't compile with newer versions of GCC. The code
allocates an array of objects that need to be initialized by
calling a constructor with one argument:

    class B;

    class A {
        B *b;

    public:
        A(B *p) : b(p) {}
    };

    class B {
    public:
        void foo() {
            // this declaration is ok
            A a(this);

            // the following causes an error with newer GCC:
            // error: ISO C++ forbids initialization in array new
            A *arr = new A[10](this);
        }
    };

    int main()
    {
        B b;
    }

This worked with g++ until version 3.3.x, but not since 3.4.x.
The problem is in the expression new A[10](this), since
according to GCC, initialization in array new is forbidden.


It's always been forbidden.

How would I initialize the array elements in ISO C++?


    std::vector< A > v( 10, this ) ;

--
James Kanze (GABI Software) email:james.kanze@gmail.com
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