(j3.2006) (SC22WG5.4773) [ukfortran] [Letter ballot 3 on Fortran 2008interpretations]

[Van Snyder]

On Tue, 2012-09-18 at 13:17 +0900, Malcolm Cohen wrote:
> 
> FWIW I agree that there is a small but important minority of users for whom 
> greater control over precisely what operations are performed would be useful. 
> In fact some might notice that I represent a large community of them!  Those 
> users are today catered for by a plethora of methods which although are not 
> guaranteed to work, do in fact work.

Portability, especially portability exploiting facilities mandated by
the standard, is actually important.

> It would be nice to support those users 
> better in the standard.  Changing the meaning of the "conversion" intrinsics 
> would not be my preferred way, but I would not necessarily be opposed to doing 
> in a revision (with added compatibility note in clause 1).  IMO we should take a 
> step back and craft such extensions properly, and I think that changing the 
> conversion intrinsics is unlikely to be the best possible method.

At last we agree.  Let's not change the conversion intrinsics.  In
particular, let's not change REAL(X,K) to be NOP.  If we change
REAL(X,K) to NOP, we cannot do it without edits.  Edits would be needed
to exempt REAL(X,K) from the provisions of 13.7.1p2, a compatibility
remark would be needed in Subclause 1.6, the description of VOLATILE
would need to be changed to encompass actions specified by the program,
and notes ought to be added to draw readers' attention to the unexpected
necessity to exploit VOLATILE to make REAL(X,K) work, including advice
to isolate REAL(X,K) in an assignment statement instead of embedding it
within an expression.