ASDF debugging on Hangouts?

[Faré]

My second attempt at a live session was also ultimately a failure:
there were interruptions, the rhythm was slow with lots of side issues,
the microphone was unplugged at one point, etc.,
and it all lasted way too many hours with lots of down time.
Happily, none of the two anonymous spectators stayed long anyway, so
no one missed much.

That said, I battled and vanquished an interesting conundrum of bugs,
all of them
directly or indirectly related to code upgrade:

* Simplest and most obvious issue: ASDF 3.3.1 renamed STAMP< to
TIMESTAMP< because the API changed; this caused a naming conflict with
LOCAL-TIME:TIMESTAMP<. Solution: in WORKOUT-TIMER's
UIOP:DEFINE-PACKAGE, use the :MIX clause with LOCAL-TIME ahead of
UIOP, instead of :USE. The backtrace pointed to the correct issue, the
ASDF changelog and/or commit messages explained what it was about,
this was obvious to find out and fix.
https://gitlab.common-lisp.net/frideau/workout-timer/commit/0e3f0104ddb26524f8445ddcf5e34dafe43aa8dd

* I had somehow compiled my SBCL with an old script that hadn't set
the SB-LINKABLE-RUNTIME feature; but CFFI-TOOLCHAIN failed to tell me,
instead failing in a cryptic way. Solution: have CFFI proactively
check for feature presence and issue a useful error message if absent.
(This is loosely related to SBCL, because CFFI failed to detect that
SBCL hadn't been upgraded to be compiled with this recent feature I
added.) This issue was compounded by the fact that, while believing
that it was an ASDF bug and trying to check at what point the bug
appeared, other issues kept cropping up because of the bug below, and
the fact that downgrading ASDF is itself quite tricky, unlike
upgrading which is trivial.
https://github.com/cffi/cffi/pull/127

* ASDF stored metadata in the :initform of operation class slots, but
then changes due to code upgrade were not visible because the slot was
already initialized (yet upgrade previously worked, once, due to
change of :allocation to :class). Solution: use defmethod, not slots.
This is a deep issue. At root was my failing to take measure of how
:initform would ultimately interact with software upgrade, when I
originally wrote this code. And yet it worked well enough so far.
Fixing the same potential issue with the (more stable but still
evolvable) code in the core of ASDF will require applying the same
solution to action.lisp all files that define new operations. This
will impact backward compatibility and will require yet another round
of going through Quicklisp fixing everything (not that many systems
define new operations, but some do), and making big announcements. ---
Good task for a candidate future maintainer: well defined and
predictable, and yet will get you around the core code of ASDF.
https://gitlab.common-lisp.net/asdf/asdf/merge_requests/89

—♯ƒ • François-René ÐVB Rideau •Reflection&Cybernethics• http://fare.tunes.org
If you don't like yourself, you *can't* like other people.
        — Robert Heinlein, "Time Enough For Love"


On Mon, Dec 4, 2017 at 11:29 AM, Faré <fahree at gmail.com> wrote:
> Well, after realizing one hour into the debugging session that I
> needed to click on a button "Start Broadcast" to go live, I'm going to
> reschedule the event, starting at 14:00 EST (19:00 UTC). Sorry.
>
> —♯ƒ • François-René ÐVB Rideau •Reflection&Cybernethics• http://fare.tunes.org
> How small of all that human hearts endure
> That part which laws or kings can cause or cure! — Samuel Johnson
>
>
> On Wed, Nov 29, 2017 at 7:24 PM, Faré <fahree at gmail.com> wrote:
>> After a kernel downgrade, I have painfully managed to get streaming to
>> Youtube Live Events working.
>> https://www.youtube.com/my_live_events
>>
>> I'm tentatively scheduled an event at 10:00 EST (15:00 UTC) on next
>> Monday December 4th 2017.
>> https://www.youtube.com/watch?v=1kq-73Cjn08
>>
>> I'll be using Hangouts on Air, and will send a message to these lists
>> with the link before I go live,
>> and also posting the link on my twitter https://twitter.com/Ngnghm
>>
>> If you have requests for an alternate time slot, I'm open to moving the session.
>>
>> —♯ƒ • François-René ÐVB Rideau •Reflection&Cybernethics• http://fare.tunes.org
>> What one person receives without working for, another person must work for
>> without receiving. — Adrian Rogers