Re: [PATCH,c++] convert cp_parser.unparsed_function_queues &co. to VECs

[Nathan Froyd <froydnj at codesourcery dot com>]

On Tue, Jun 08, 2010 at 08:30:55AM -0700, Mark Mitchell wrote:
> Nathan Froyd wrote:
> > -      for (TREE_PURPOSE (parser->unparsed_functions_queues)
> > -	     = nreverse (TREE_PURPOSE (parser->unparsed_functions_queues));
> > -	   (queue_entry = TREE_PURPOSE (parser->unparsed_functions_queues));
> > -	   TREE_PURPOSE (parser->unparsed_functions_queues)
> > -	     = TREE_CHAIN (TREE_PURPOSE (parser->unparsed_functions_queues)))
> > +      for (ix = 0;
> > +	   VEC_iterate (cp_default_arg_entry, unparsed_funs_with_default_args,
> > +			ix, e);
> > +	   ix++)
> 
> Does this still iterate through things in the same order?  That's
> important, IIRC.  I couldn't quite follow the changes to build up and
> iterate through these lists, but would you please double-check?  If you
> do need to reverse the iteration, that's an obvious change; just post
> the final patch after check-in.

That's a good question.  In fact, I couldn't follow things either the
first time I wrote the patch and iterated from len-1..0.  When testing
that version, however, there were testsuite failures in testcases
dealing with default arguments.

In pictures, before this change, we accumulated things:

  .. -> C -> B -> A

and then reversed them to iterate:

  A -> B -> C -> ...

But now we accumulate in the "correct" order:

  [A, B, C, ...]

so there's no need to do the reversal.

Thanks for the review, will check in after trunk unfreezes.

-Nathan