Geoff's reasoning seems quite sound. +1 for February release. On Feb 7, 2013, at 3:50 AM, Geoffrey Mainland wrote:

In practice the versions of GHC that are widely used are those that are included in the platform. Maybe we should coordinate with their next release? They are targeting a May 6 release, and the release process is starting March 4, so it sounds like the original GHC release plan (February release) would be a good fit for the platform as it would allow library writers to catch up and ensure that STABLE was tested enough for inclusion in the platform. It would be a shame to miss the platform release.

Geoff

On 02/07/2013 08:25 AM, Simon Peyton-Jones wrote:

...

Dear GHC users,

* *

*Carter*: Will this RTS update make it into ghc 7.8 update thats coming up in the next monthish?

*Andreas*: We are almost there - we are now trying to sort out a problem on mac os x. It would be helpful to know if there is a cutoff date for getting things into 7.8.

Simon, Ian, and I have just been discussing 7.8, and would be interested in what you guys think.

At ICFP we speculated that we’d make a release of GHC soon after Christmas to embody tons of stuff that has been included since 7.6, specifically:

· major improvements in DPH (vectorisation avoidance, new vectoriser)

· type holes

· rebindable list syntax

· major changes to the type inference engine

· type level natural numbers

· overlapping type families

· the new code generator

· support for vector (SSE/AVX) instructions

Whenever it comes it would definitely be great to include Andreas & friends’ work:

· Scheduler changes to the RTS to improve latency

The original major reason for proposing a post-Xmas release was to get DPH in a working state out into the wild. However, making a proper release imposes costs on everyone else. Library authors have to scurry around to make their libraries work, etc. Some of the new stuff hasn’t been in HEAD for that long, and hence has not been very thoroughly tested. (But of course making a release unleashes a huge wave of testing that doesn’t happen otherwise.)

So another alternative is to leave it all as HEAD, and wait another few months before making a release. You can still use all the new stuff by compiling HEAD, or grabbing a snapshot distribution. And it makes it hard for the Haskell platform if GHC moves too fast. Many people are still on 7.4.

There seem to be pros and cons each way. I don’t have a strong opinion. If you have a view, let us know.

Simon

_______________________________________________ Glasgow-haskell-users mailing list Glasgow-haskell-users@haskell.org http://www.haskell.org/mailman/listinfo/glasgow-haskell-users

I'm not too optimistic we could actually get the final release out during February, assuming we want to allow a couple of weeks for people to test an RC. Does the Haskell Platform actually want to commit to using a GHC release with "tons of [new] stuff", that has had little testing, days or weeks after its release? I thought the idea was that it would favour known-good releases over the latest-and-greatest, but perhaps I misunderstood or the philosophy has changed. Thanks Ian On Thu, Feb 07, 2013 at 09:00:37AM -0500, Richard Eisenberg wrote:

Geoff's reasoning seems quite sound. +1 for February release.

On Feb 7, 2013, at 3:50 AM, Geoffrey Mainland wrote:

...

In practice the versions of GHC that are widely used are those that are included in the platform. Maybe we should coordinate with their next release? They are targeting a May 6 release, and the release process is starting March 4, so it sounds like the original GHC release plan (February release) would be a good fit for the platform as it would allow library writers to catch up and ensure that STABLE was tested enough for inclusion in the platform. It would be a shame to miss the platform release.

Geoff

On 02/07/2013 08:25 AM, Simon Peyton-Jones wrote:

...

Dear GHC users,

* *

*Carter*: Will this RTS update make it into ghc 7.8 update thats coming up in the next monthish?

*Andreas*: We are almost there - we are now trying to sort out a problem on mac os x. It would be helpful to know if there is a cutoff date for getting things into 7.8.

Simon, Ian, and I have just been discussing 7.8, and would be interested in what you guys think.

At ICFP we speculated that we’d make a release of GHC soon after Christmas to embody tons of stuff that has been included since 7.6, specifically:

· major improvements in DPH (vectorisation avoidance, new vectoriser)

· type holes

· rebindable list syntax

· major changes to the type inference engine

· type level natural numbers

· overlapping type families

· the new code generator

· support for vector (SSE/AVX) instructions

Whenever it comes it would definitely be great to include Andreas & friends’ work:

· Scheduler changes to the RTS to improve latency

The original major reason for proposing a post-Xmas release was to get DPH in a working state out into the wild. However, making a proper release imposes costs on everyone else. Library authors have to scurry around to make their libraries work, etc. Some of the new stuff hasn’t been in HEAD for that long, and hence has not been very thoroughly tested. (But of course making a release unleashes a huge wave of testing that doesn’t happen otherwise.)

So another alternative is to leave it all as HEAD, and wait another few months before making a release. You can still use all the new stuff by compiling HEAD, or grabbing a snapshot distribution. And it makes it hard for the Haskell platform if GHC moves too fast. Many people are still on 7.4.

There seem to be pros and cons each way. I don’t have a strong opinion. If you have a view, let us know.

Simon

Hi all, Ian Lynagh wrote:

Does the Haskell Platform actually want to commit to using a GHC release with "tons of [new] stuff", that has had little testing, days or weeks after its release? I thought the idea was that it would favour known-good releases over the latest-and-greatest, but perhaps I misunderstood or the philosophy has changed.

From a teaching perspective, I'd hope the philosophy is still "known-good releases". The Haskell platform is what we deploy on our teaching machines, and we really need to be able to trust that it will work very smoothly, or we'd risk losing lots of valuable teaching time and, even worse, putting lots of students off Haskell. (Getting students to appreciate Haskell is an upwards struggle at the best of times anyway.) Something like new run-time system features sounds like something that really ought to be tested very thoroughly before being integrated into the HP. So, for (general) teaching, at least, stability over new features any day. Best, /Henrik -- Henrik Nilsson School of Computer Science The University of Nottingham nhn@cs.nott.ac.uk This message and any attachment are intended solely for the addressee and may contain confidential information. If you have received this message in error, please send it back to me, and immediately delete it. Please do not use, copy or disclose the information contained in this message or in any attachment. Any views or opinions expressed by the author of this email do not necessarily reflect the views of the University of Nottingham. This message has been checked for viruses but the contents of an attachment may still contain software viruses which could damage your computer system: you are advised to perform your own checks. Email communications with the University of Nottingham may be monitored as permitted by UK legislation.