Re: Perl 5.13.3+ MAY BREAK COMPILED DRIVERS - Please test DBI 1.613_71!

On Sun, Sep 05, 2010 at 05:17:45PM -0700, Darren Duncan wrote:
> Okay, I'm not sure I understand the problem here.
> 
> I thought that the point of PERL_POLLUTE was to provide things that
> were removed from the Perl core so that code which depends on the
> old removed APIs would continue to work with newer Perls that
> removed them if said code enables PERL_POLLUTE.

PL_sv_undef, for example, used to be called just sv_undef many years ago.

When it was decided to to add the PL_ prefix the PERL_POLLUTE #define
was added as a way for old code to keep working without changes.
It does #define sv_undef PL_sv_undef etc etc.

Perl 5.13.4+ removes that mechanism and those #defines so code still
using the non-prefixed names will break.

> DBD::SQLite *does* define PERL_POLLUTE, but if I take it out, then
> it still builds fine otherwise as-is on Perl 5.13.4 with DBI
> 1.613_71.  So DBD::SQLite already appears to use the newer PL_
> versions, so hence what is PERL_POLLUTE for?

Looks like DBD::SQLite doesn't need it. That's good.

> I found that under Perl 5.12.1, just removing PERL_POLLUTE caused
> build failures, which cited old versions without the PL_, but then I
> found that these old versions weren't in the DBD::SQLite source at
> all, but rather were being added by ppport.h.  So then when I also
> removed ppport.h (and PERL_POLLUTE), then DBD::SQLite built with
> Perl 5.12.1 and DBI 1.613_71.

Okay. If your ppport.h isn't recent that may suggest a bug in ppport.h.

> So, in light of this, should I actually be changing anything in
> DBD::SQLite?  Or should it be retaining both the PERL_POLLUTE and
> ppport.h?

You can remove PERL_POLLUTE. ppport.h has other uses and should be kept.
(Though ppport.h can tell you that for itself when you run in on the code.)

> You seemed to be saying that including PERL_POLLUTE means broken on
> Perl 5.13.4 but that doesn't seem to be the case.

No, including PERL_POLLUTE simply becomes ineffective on 5.13.4+.

So _if_ your driver _needed_ PERL_POLLUTE then it'll fail on 5.13.4+.

Tim.