Re: [bug-gawk] Increased RAM memory usage in gawk 5.0.1 compared to gawk 4.1.4

[Andrew J. Schorr]

On Wed, Aug 28, 2019 at 04:08:00PM -0400, Andrew J. Schorr wrote:
> This patch fixes my test case (bug5), but is not more generally correct (it
> does not pass make check, dumping core on rebt8b2 and hanging on regexprange
> and failing sortu):
> 
> diff --git a/interpret.h b/interpret.h
> index 3215833..4820716 100644
> --- a/interpret.h
> +++ b/interpret.h
> @@ -1065,6 +1065,8 @@ match_re:
>                       if (op != Op_match_rec) {
>                               decr_sp();
>                               DEREF(t1);
> +                             if (m->type == Node_dynregex)
> +                                     DEREF(m->re_exp);
>                       }
>                       r = node_Boolean[di];
>                       UPREF(r);
> 
> Arnold -- do you have any insight into the correct fix?

Ah, OK, I see that m->re_exp was getting DEREF'ed under Op_match on a delayed
basis, but that doesn't work when the dynamic regexp was in a field variable.
The attached patch seems to fix Finn's problem and passes "make check"
and "make valgrind-noleak". But I'm still not 100% confident that it's
right. Arnold -- can you please review this?  My understanding of
the Node_dynregex mechanism is not great, and it makes me a bit nervous
to set m->re_exp without first DEREF'ing its contents. But it seems
to work.

And Finn, if easy, please test this.

Thanks,
Andy

dynregex.field.patch
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