[Python-Dev] #12982: Should -O be required to read .pyo files? (original) (raw)

Maciej Fijalkowski fijall at gmail.com
Thu Jun 14 12:11:42 CEST 2012

On Wed, Jun 13, 2012 at 9:13 PM, R. David Murray <rdmurray at bitdance.com>wrote:

On Wed, 13 Jun 2012 20:46:50 +0200, Antoine Pitrou <solipsis at pitrou.net> wrote: > On Wed, 13 Jun 2012 11:20:24 -0700 > Toshio Kuratomi <a.badger at gmail.com> wrote: > > On Wed, Jun 13, 2012 at 01:58:10PM -0400, R. David Murray wrote: > > > > > > OK, but you didn't answer the question :). If I understand correctly, > > > everything you said applies to writing the bytecode, not reading it. > > > > > > So, is there any reason to not use the .pyo file (if that's all that is > > > around) when -O is not specified? > > > > > > The only technical reason I can see why -O should be required for a .pyo > > > file to be used (if it is the only thing around) is if it won't run > > > without the -O switch. Is there any expectation that that will ever be > > > the case? > > > > > Yes. For instance, if I create a .pyo with -OO it wouldn't have docstrings. > > Another piece of code can legally import that and try to use the docstring > > for something. This would fail if only the .pyo was present. > > Not only docstrings, but also asserts. I think running a pyo without -O > would be a bug.

Again, a program that depends on asserts is buggy. As Ethan pointed out we are asking about the case where someone is deliberately setting the .pyo file up to be run as the "normal" case. I'm not sure we want to support that, I just want us to be clear about why we don't :)

PyPy toolchain is an example of such buggy program. And oh any tests. I would not be impressed if my python read .pyo files out of nowhere when not running with -O flag (I'm trying very hard to never run python with -O, because it's different python after all) -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://mail.python.org/pipermail/python-dev/attachments/20120614/60e3319b/attachment.html>

More information about the Python-Dev mailing list