Re: RValue Arrays

On Jul 22, 1:10 am, Gabriel Dos Reis <g...@[EMAIL PROTECTED]
> wrote:
> David Abrahams <d...@[EMAIL PROTECTED]
> writes:
> |
> | Now
> |          X()
> |
> | is an rvalue of type X and
> |
> |          X().a
> |
> | would be an rvalue array... if I'm not mistaken, that is ;-)
>
> Yes, that is correct.  A disturbing point is that all components of that
> rvalue array are lvalues!  This defect was inherited from C90 which
> did not appreciate the existence of rvalue arrays.
>

According to Comeau's online compiler, in C89 an expression accessing
a component of an rvalue array *is* itself an rvalue. Not in C++, as
you say.

Here's the code I put through the online compiler (compiles in C99 and
C++, not in C89):

   typedef struct
   {
     int a[10];
   } X;

   X MakeX();

   void test()
   {
     int* p = &MakeX().a[3];
   }


James


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