[perl #129916] CV symbol table optimization only works in main::

Hi Father Chrysostomos, Todd R. and I checked your branch sprout/cv-in-stash and had a look at the issue from the extract from t/op/local.t, which is failing.

Hope this patch could help, but looks like the OP multideref is not calling the Perl_mro_method_changed_in via a regular save_gp call.

We came with this lazy solution (view attached patch) which force to upgrade the RV/CV to a GV. 
As these cases are probably uncommon, I think it's a solution we could consider when using local on a CV.

Also, notice that some other OPs might require the same kind of action.
I’ve also attached to this case a simple test (with some comments) to show the problem.

sincerely
nicolas

On Thu, 21 Sep 2017 09:34:42 -0700, sprout wrote:
> On Mon, 18 Sep 2017 09:00:58 -0700, atoomic wrote:
> > On Mon, 28 Aug 2017 20:33:55 -0700, sprout wrote:
> > > On Wed, 19 Oct 2016 07:20:42 -0700, mauke- wrote:
> > > >
> > > > This is a bug report for perl from l.mai@web.de,
> > > > generated with the help of perlbug 1.40 running under perl
> > > > 5.24.0.
> > > >
> > > >
> > > > -----------------------------------------------------------------
> > > > [Please describe your issue here]
> > > >
> > > > Here's the merge I'm talking about:
> > > > http://perl5.git.perl.org/perl.git/commitdiff/f9d9e965
> > > >
> > > > Also listed in perl5220delta:
> > > >
> > > > Subroutines in packages no longer need to be stored in typeglobs:
> > > > declaring a subroutine will now put a simple sub reference
> > > > directly
> > > > in
> > > > the stash if possible, saving memory.
> > > >
> > > > This works fine for the main script:
> > > >
> > > > $ perl -wE 'sub foo { 42 } say $main::{foo}'
> > > > CODE(0xa06f668)
> > > >
> > > > But not in other packages:
> > > >
> > > > $ perl -wE 'package Other; sub foo { 42 } say $Other::{foo}'
> > > > *Other::foo
> > > >
> > > > I.e. this optimization doesn't apply to modules, which is where
> > > > most
> > > > subroutines come from.
> > >
> > > Fixing it causes this to fail:
> >
> > Could you precise the 'fixing it' part. Where/what is the patch with
> > your fix candidate ? is there any commit id / topic branch where we
> > could read your attempt to fix it ?
> 
> Due to test failures, I had not actually committed it yet.  But now I
> have.  It is the ‘unfinished’ commit on the sprout/cv-in-stash branch.
> 
> 
> >
> > >
> > > use Test::More tests => 1;
> > >
> > > package Other;
> > >
> > > sub f1 { "f1" }
> > > local $Other::{"f1"} = sub { "h1" };
> > > ::is(f1(), "h1", "localised sub via stash");
> > >
> > > Does this matter?  This is pretty obscure code (from t/op/local.t)
> > > that should probably be doing local *Other::f1 = sub { "h1" }
> > > instead
> > > (if it were production code).



---
via perlbug:  queue: perl5 status: open
https://rt.perl.org/Ticket/Display.html?id=129916

• [perl #129916] CV symbol table optimization only works in main:: by Atoomic via RT
• [perl #129916] CV symbol table optimization only works in main:: by Father Chrysostomos via RT
• [perl #129916] CV symbol table optimization only works in main:: by Father Chrysostomos via RT
• [perl #129916] CV symbol table optimization only works in main:: by Father Chrysostomos via RT
• [perl #129916] CV symbol table optimization only works in main:: by Atoomic via RT
• [perl #129916] CV symbol table optimization only works in main:: by Father Chrysostomos via RT
• [perl #129916] CV symbol table optimization only works in main:: by Atoomic via RT
• [perl #129916] CV symbol table optimization only works in main:: by Atoomic via RT
• [perl #129916] CV symbol table optimization only works in main:: by Father Chrysostomos via RT