Thread overview
regressions
Jun 30, 2017
Martin Krejcirik
Jun 30, 2017
Seb
Jun 30, 2017
jmh530
Jun 30, 2017
ag0aep6g
Jun 30, 2017
H. S. Teoh
Jul 02, 2017
Vladimir Panteleev
Jul 02, 2017
Brad Roberts
June 30, 2017
DMD, Phobos and Druntime open regressions over time:

http://bid.iline.cz/~mk/tmp/regs.png

Used to be stable, but seems to be getting worse since 2016.

June 30, 2017
On Friday, 30 June 2017 at 12:48:12 UTC, Martin Krejcirik wrote:
> DMD, Phobos and Druntime open regressions over time:
>
> http://bid.iline.cz/~mk/tmp/regs.png
>
> Used to be stable, but seems to be getting worse since 2016.

I think this depends on your PoV. Thanks to the growing community and more automation (Project-Tester, Martin's nightly build and finally daily crons on Travis [1]), it's a lot easier to detect regressions.

Btw, in case anyone wants to prevent regressions for their project(s). There are two easy ways:

1) Add it to the Project-Tester which is run on _every_ PR for {dmd,druntime,phobos} (-> make a PR to dlang/ci)
2) Enable daily crons [1] and add `dlang-nightly` to your list of D compilers on Travis


[1] https://blog.travis-ci.com/2016-12-06-the-crons-are-here
June 30, 2017
On Friday, 30 June 2017 at 16:44:54 UTC, Seb wrote:
>
> Btw, in case anyone wants to prevent regressions for their project(s). There are two easy ways:
>
> 1) Add it to the Project-Tester which is run on _every_ PR for {dmd,druntime,phobos} (-> make a PR to dlang/ci)
> 2) Enable daily crons [1] and add `dlang-nightly` to your list of D compilers on Travis
>
>
> [1] https://blog.travis-ci.com/2016-12-06-the-crons-are-here

Blog post worthy?
July 01, 2017
On 06/30/2017 02:48 PM, Martin Krejcirik wrote:
> DMD, Phobos and Druntime open regressions over time:
> 
> http://bid.iline.cz/~mk/tmp/regs.png
> 
> Used to be stable, but seems to be getting worse since 2016.

It's probably no coincidence that Kenji's last commits have been in 2016:

https://github.com/dlang/dmd/commits/master?author=9rnsr
June 30, 2017
On Sat, Jul 01, 2017 at 12:57:35AM +0200, ag0aep6g via Digitalmars-d wrote:
> On 06/30/2017 02:48 PM, Martin Krejcirik wrote:
> > DMD, Phobos and Druntime open regressions over time:
> > 
> > http://bid.iline.cz/~mk/tmp/regs.png
> > 
> > Used to be stable, but seems to be getting worse since 2016.
> 
> It's probably no coincidence that Kenji's last commits have been in 2016:
> 
> https://github.com/dlang/dmd/commits/master?author=9rnsr

Whatever happened to Kenji?  He just kinda went missing without any notice... and then popped in after a few months saying he's back, but then he disappeared again and we never heard from him again.


T

-- 
Right now I'm having amnesia and deja vu at the same time. I think I've forgotten this before.
July 02, 2017
On Friday, 30 June 2017 at 12:48:12 UTC, Martin Krejcirik wrote:
> DMD, Phobos and Druntime open regressions over time:
>
> http://bid.iline.cz/~mk/tmp/regs.png
>
> Used to be stable, but seems to be getting worse since 2016.

One thing that might have contributed to that is that until a year or two ago, we weren't really checking whether filed bugs were regressions. As it turns out, a good deal of the time when someone runs into a bug, they don't even realize that it's some behaviour that used to work previously. This is why you will occasionally see recently-filed bugs that are marked as regressions in very old versions, likely older than since the submitter started using D.

Knowing whether a bug is a regression is useful because then you can track down the change that caused it, and it's often much easier to find the bug in a small diff and fix it. The downside is that it makes the meaning of the "regression" severity less useful when tracking how many of those issues actually broke someone's code (that we know about), which is why the regressing version is prefixed in issue summaries.

July 02, 2017
On 7/2/2017 7:27 AM, Vladimir Panteleev via Digitalmars-d wrote:
> On Friday, 30 June 2017 at 12:48:12 UTC, Martin Krejcirik wrote:
>> DMD, Phobos and Druntime open regressions over time:
>>
>> http://bid.iline.cz/~mk/tmp/regs.png
>>
>> Used to be stable, but seems to be getting worse since 2016.
>
> One thing that might have contributed to that is that until a year or two ago, we weren't really checking whether filed bugs were regressions. As it turns out, a good deal of the time when someone runs into a bug, they don't even realize that it's some behaviour that used to work previously. This is why you will occasionally see recently-filed bugs that are marked as regressions in very old versions, likely older than since the submitter started using D.
>
> Knowing whether a bug is a regression is useful because then you can track down the change that caused it, and it's often much easier to find the bug in a small diff and fix it. The downside is that it makes the meaning of the "regression" severity less useful when tracking how many of those issues actually broke someone's code (that we know about), which is why the regressing version is prefixed in issue summaries.

One of the biggest issues is that for a small period of time a few years ago, releases were actually gated on fixing regressions.  That stopped at some point and the backslide has gotten pretty bad. There was a period where there was exactly one open regression. It's one of my big disappointments in the current dev/release cycles.  That said, since I really haven't been participating in active development, I tend to just bite my tongue and say nothing. Holding to a line of no known regressions is a critical aspect of incrementally better releases.