[Scons-users] Unexpected messge with configure

[Bill Deegan]

Jason,

That seems reasonable, but maybe not simple..

_Bill

On Fri, Sep 7, 2018 at 2:10 PM Jason Kenny <dragon512 at live.com> wrote:

> My first thoughts are that if we can tell if the result is cached to
> return that value. If there are no cached values do the current behavior. I
> am not sure how hard this would be however at the moment.
> ideally the best behavior I think might be
>
>    - configure item has no cached value. Error as we currently do
>    - configure item is cached, return the cached value
>    - if we can detect that it has changed and would normally re-execute
>       print a warning message that this is the case and note that the result of
>       the build may change when it really runs
>       - Not sure what to do with the cases of configuring items that
>    don't cache ( such as custom functions that the user might have defined in
>    a certain way ).
>
> Jason
> ------------------------------
> *From:* Scons-users <scons-users-bounces at scons.org> on behalf of Bill
> Deegan <bill at baddogconsulting.com>
> *Sent:* Friday, September 7, 2018 12:28 PM
> *To:* SCons users mailing list
> *Subject:* Re: [Scons-users] Unexpected messge with configure
>
> Jason,
>
> I'd say it's not a known issue, it's expected behavior.
> See the docstring for the exception in question.
>
> What do you think SCons should do in this case?
> The dry run would likely be affected by the results of any configure
> checks which might write a file or run a process (both things which scons
> is not supposed to do with --dry-run), so it's likely not possible to do a
> dry-run with configure checks which write to the filesystem?
>
> -Bill
>
> class ConfigureDryRunError(SConfError):
> """Raised when a file or directory needs to be updated during a Configure
> process, but the user requested a dry-run"""
> def __init__(self,target):
> if not isinstance(target, SCons.Node.FS.File):
> msg = 'Cannot create configure directory "%s" within a dry-run.' % str
> (target)
> else:
> msg = 'Cannot update configure test "%s" within a dry-run.' % str(target)
> SConfError.__init__(self,msg)
>
>
> On Fri, Sep 7, 2018 at 1:20 PM Bill Deegan <bill at baddogconsulting.com>
> wrote:
>
> Mats,
>
> How long does:
> scons --help non-existant-target
> Take?
>
> -Bill
>
> On Fri, Sep 7, 2018 at 12:26 PM Mats Wichmann <mats at wichmann.us> wrote:
>
> On 09/07/2018 09:55 AM, Jason Kenny wrote:
> > I was adding some configure logic to a build I am working on. When doing
> a dry run i now get this error:
> >
> > scons: *** Cannot update configure test ".sconf_temp/conftest_0" within
> a dry-run.
> > File "./../scons-3.0.1/SCons/Script/SConscript.py", line 614, in __call__
> >
> > Is this a known issue with using configure in scons?
>
> I've run into it (you'll find my name on such questions in the mailing
> list archive, afair).
>
> When you stop and think about it, running a configure test which means
> compiling code sort of doesn't fit the definition of "dry run", though.
>
> this is a gray area to my way of thinking.  steps like cleaning, getting
> help, and doing a dry-run are places where you don't want external work
> to happen, just have scons go through the rules.  but sometimes you
> don't know what all the dependencies actually are before you've run some
> of those steps.
>
> we'll wait for the actual experts to pipe up :)
>
> ======
> Aside:
> on the project I'm trying to gradually bend into shape (it had lived for
> a couple of years before I came around), which uses a variant directory
> build, starting with the variant directory completely absent, "scons
> --help" takes seven seconds, and leaves a variant directory with 12
> object files and four libraries built. I *KNOW* that's wrong, but I
> haven't yet figured out how to fix it without either breaking
> everything, or special-casing stuff all over the place like
>
> if not env.GetOption('help') and not env.GetOption('clean'):
>
> guess we could put GetOption('dry-run') in that list too (would we have
> to include all of the variants of that name? -n, --no-exec,
> --just-print, --dry-run, --recon)
>
> with 200+ sconscripts, adding those cases is not appealing.
>
> _______________________________________________
> Scons-users mailing list
> Scons-users at scons.org
> https://pairlist4.pair.net/mailman/listinfo/scons-users
> <https://nam03.safelinks.protection.outlook.com/?url=https%3A%2F%2Fpairlist4.pair.net%2Fmailman%2Flistinfo%2Fscons-users&data=02%7C01%7C%7C9710a3affd9d4dfcc70d08d614e76e4f%7C84df9e7fe9f640afb435aaaaaaaaaaaa%7C1%7C0%7C636719381543572547&sdata=QVADywe8YsHd4BMjUt2rj1L%2F2NA3Sku%2F1LN9Sun12vo%3D&reserved=0>
>
> _______________________________________________
> Scons-users mailing list
> Scons-users at scons.org
> https://pairlist4.pair.net/mailman/listinfo/scons-users
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <https://pairlist4.pair.net/pipermail/scons-users/attachments/20180907/4995ef8d/attachment.html>