[Patch, fortran] PR29422 and PR29428 - allocatable component wrinkles

[Brooks Moses]

François-Xavier Coudert wrote:
> About that: I've thought again, and I think the best we can do is to
> actually add the extra code in the {L,U}BOUND intrinsic. gfortran uses
> 0-based temporaries and incorrect bounds for many array functions
> return values, but it doesn't matter at all. It's all internal code,
> the only place where it shows up is when you call {L,U}BOUND, because
> it gets the value directly from the descriptor.
> 
> I'm now working on a very different solution to PR29391, where LBOUND
> actually checks whether its argument is "a whole array or array
> structure component", whether it is "an assumed-size array of rank
> DIM, or has extent zero in dimension DIM" and fetch the descriptor
> bounds only in this case (and in this case, I believe that they
> descriptor bound values are always "right"); in other cases, it
> returns 1 (or, for UBOUND, returns the number of elements in this
> dimension).
> 
> What do you think about that?

Note that, when we do implement array assignments with allocation, this 
issue will likely turn up again.  This can be avoided by directly using 
the LBOUND code in that case, though -- which seems appropriate, since 
the Fortran Standard uses the LBOUND intrinsic to define how those 
assignments work!

- Brooks