This is the mail archive of the gcc-patches@gcc.gnu.org mailing list for the GCC project.


Index Nav: [Date Index] [Subject Index] [Author Index] [Thread Index]
Message Nav: [Date Prev] [Date Next] [Thread Prev] [Thread Next]
Other format: [Raw text]

Re: [Patch, Fortran, OOP] PR 44962: [OOP] ICE with specification expression SIZE(<CLASS>)


On Sun, Jul 18, 2010 at 07:55:13PM +0200, Janus Weil wrote:
> Hi Steve,
> 
> >> 3) In gfc_is_constant_expr, I'm adding a special case for the RAND()
> >> and IRAND() intrinsic functions, which were detected to be constant
> >> before. [I'm assuming that a "constant expression" is something that
> >> can be reduced to a constant at compile time, which the random
> >> functions are clearly not.]
> >
> > I think that this part is the wrong way to address the issue.
> 
> what do you think would be a better way?

I don't know, yet.  But, special casing these two intrinsics
in gfc_is_constant_expr seems wrong.  With hundreds of intrinsics
procedures, are these the only 2 that need this special handling?
If yes, then why?  If no, then we need to add special casing for
all intrinsics.

> > In looking at intrinsics.c, I see that neither rand nor irand
> > have simplification procedures.
> 
> Of course not. How could they? They will not be simplifyable at
> compile time in any way ...

Sorry, misread your comment.  I was thinking about something
like 'i = irand(j)' verseus 'i = irand(23)' where the argument
is optional.

With the toy programs I've written this morning involving rand(),
f951 never enter gfc_is_constant_expr().  Do you have a small
example that exhibits this problem?

-- 
Steve


Index Nav: [Date Index] [Subject Index] [Author Index] [Thread Index]
Message Nav: [Date Prev] [Date Next] [Thread Prev] [Thread Next]