- ghc-devs - Haskell.org

GHC MinGW distribution
by Robin KAY 18 Jun '14

18 Jun '14

Dear All, I wanted to enquire about the prospects for updating the version of MinGW which ships with the Windows binary distribution of GHC. The version included as of 7.8.2 is now several years old and in some cases I've found that it's incompatible with the libraries produced by newer versions of MinGW (as to be expected, per my understanding). Specifically, my HsQML binding for Qt can't be used with the libraries from the official Windows binary distribution of Qt 5 because the resulting executables crash on start-up with runtime incompatibilities. I'm in the process of trying to build out-of-the-box compatible Qt binaries against GHC's MinGW, but Qt's stated minimum requirements on the tool-chain version aren't encouraging. The only way I currently have of making this work is for users to edit their GHC settings file to point GHC at a version of gcc.exe from a newer MinGW (such as the one which ships with Qt). The fact that this seems to work is encouraging, but it's still a bit of a difficult process to put people through. I know that Windows developers are in short supply, so I would like to offer what assistance I can in making this happen. There appear to be copies of MinGW stored in the GHC repository at http://git.haskell.org/ghc-tarballs.git/tree . Does the build system use these automatically or are they just there for reference? Thanks, -- Robin KAY

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Offering GHC builder build slaves
by Alain O'Dea 18 Jun '14

18 Jun '14

-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 Hi folks: I have successfully built Ian Lynagh's GHC builder on Ubuntu and SmartOS and I would like to offer build slaves based on Carter's mirroring of the code to https://github.com/cartazio/ghc-builder. I can offer several build slaves, but I'm not sure what the process is. How do I run multiple build slaves? Do I need a separate username for each? Is there a username convention? The suggestion at https://ghc.haskell.org/trac/ghc/wiki/Builder is that I post a username and password to ghc@. There are two issues with this: 1. ghc@ does not exist as far as I can tell 2. Posting a password to a mailing list will make it publicly accessible and allow others to impersonate my build slaves I am happy to send this information if the admins of the GHC builder infrastructure are comfortable with the risks. Alternatively, I am able to send this via GPG encrypted email given the public key and email of an admin. Feel free to contact me on or off list about this. Best, Alain -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.14 (GNU/Linux) Comment: Using GnuPG with Thunderbird - http://www.enigmail.net/ iQEcBAEBAgAGBQJTQ0uTAAoJEP0rIXJNjNSA+fMH/2p9yeWgpfDeaTHilur5qoZ6 6DZiktJgvMpVeqFwHyaFMk+ubEp8/xU/VUrOEztr01jmzNLS2UoqDVH/7EZPZPtV 0ONh/bcYYA8EBa9SCqaVXVb9I8EdDE6w2cQGDqnwHqaFerAUqv8OiQEWyJCuJSdr 7EL/vcacNfr5Ix4oG2pkESvEJBHHEN4ZTXoKeJnyQT93o2RaC1fgImm6F6tgpdQE Jh+QInIX1dRuSl+pDlHg6kbLZqFG8Mnyz0bcWuUL2ekGQBp3HtT0MwonM9HUTmmG 0baRYUaK/moO5Q6lUXhI2eRT/UFl4qnzwJw/sIVuaL7h1Ikj0ZMOuPs0GjfRbY8= =/Rwk -----END PGP SIGNATURE-----

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Deep embeddings and Arrows Re: Uniquable RdrName instance
by Carter Schonwald 18 Jun '14

18 Jun '14

to clarify: having bind would be equivalent to having arr for the purposes of my question (assuming its the standard monadic bind). having arr :: (b -> c) -> a b c is tantamount to assuming that any haskell function can be embedded in an arrow instance which prevents a lot of interesting deep embedding uses of the Arrow abstraction/ or at least makes it a bit tricker. (eg things like writing circuits or certain types of compiled FRP models). On Tue, Jun 17, 2014 at 4:06 AM, Jan Stolarek <jan.stolarek(a)p.lodz.pl> wrote: > > FYI it's #7828, not #7282. > Of course, yes. > > > would making arrow remindable involve dropping the arr == haksell > functions assumption or doing > > something that would allow generalized arrows? > Not sure if I fully understand what you mean. There's an idea to give up > on current desugaring > that heavily uses arr, >>> etc. in favor of desugaring based on bind > equivalents for arrows. Is > this what you wanted to know? There's some discussion on the Trac you > might want to follow. > > Janek > _______________________________________________ > ghc-devs mailing list > ghc-devs(a)haskell.org > http://www.haskell.org/mailman/listinfo/ghc-devs >

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RE: Regression in the typechecker in GHC 7.8.2
by Simon Peyton Jones 16 Jun '14

16 Jun '14

Copying ghc-devs. Oleg says: | Sorry for reporting a problem via e-mail. It seems track no | longer accepts anonymous (guest) submissions. When I tried to register | the account I was told that my submission is a spam. The tracker is | really well protected. Can anyone help him? I'll open a ticket. Simon | -----Original Message----- | From: oleg(a)okmij.org [mailto:oleg@okmij.org] | Sent: 16 June 2014 11:46 | To: Simon Peyton Jones | Subject: Regression in the typechecker in GHC 7.8.2 | | | Hello! | | Sorry for reporting a problem via e-mail. It seems track no | longer accepts anonymous (guest) submissions. When I tried to register | the account I was told that my submission is a spam. The tracker is | really well protected. | | Here is the problem: what used to type check in GHC 7.4.1 (and I think | in 7.6.2, although I no longer have access to that version) fails in GHC | 7.8.2. | | The following program type-checks with GHC 7.4.1 and GHC 7.8.2: | | {-# LANGUAGE RankNTypes #-} | {-# LANGUAGE TypeFamilies #-} | | module T where | | foo :: (forall f g. (Functor f) => f a -> f b) -> [a] -> [b] | -- foo :: (forall f g. (Functor f, g ~ f) => g a -> g b) -> [a] -> [b] | foo tr x = tr x | | t = foo (fmap not) [True] | | The following code (which differs only in the signature of foo) | | {-# LANGUAGE RankNTypes #-} | {-# LANGUAGE TypeFamilies #-} | | module T where | | -- foo :: (forall f g. (Functor f) => f a -> f b) -> [a] -> [b] foo :: | (forall f g. (Functor f, g ~ f) => g a -> g b) -> [a] -> [b] foo tr x = | tr x | | t = foo (fmap not) [True] | | | type-checks with 7.4.1 but not with 7.8.2. The latter reports the error | | Couldn't match type `b' with `Bool' | `b' is untouchable | inside the constraints (Functor f, g ~ f) | bound by a type expected by the context: | (Functor f, g ~ f) => g Bool -> g b | at /tmp/t.hs:12:5-25 | `b' is a rigid type variable bound by | the inferred type of t :: [b] at /tmp/t.hs:12:1 | Expected type: Bool -> b | Actual type: Bool -> Bool | Relevant bindings include t :: [b] (bound at /tmp/t.hs:12:1) | In the first argument of `fmap', namely `not' | In the first argument of `foo', namely `(fmap not)' | | Giving t the type signature [Bool] fixes the problem. Alas, I come | across the similar untouchable error in situations where giving the type | signature is quite difficult (in local bindings, with quite large | types). | | Sorry again for the off-line report, | Oleg

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Getting error about unused instances during "sh validate"
by Alfredo Di Napoli 13 Jun '14

13 Jun '14

Hello guys, am I the only one to get the following when I run "sh validate"? libraries/base/Data/Maybe.hs:139:1: Warning: Defined but not used: ‘mapMaybeFB’ <no location info>: Failing due to -Werror. make[1]: *** [libraries/base/dist-install/doc/html/base/base.haddock] Error 1 make[1]: *** Waiting for unfinished jobs.... make: *** [all] Error 2 I'm working on this ticket, but I can't see how that can be related: https://ghc.haskell.org/trac/ghc/ticket/8226 Thanks! Alfredo

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HEADS-UP: diagrams does not compile with HEAD (regressions)
by Gabor Greif 12 Jun '14

12 Jun '14

Devs, as of recently GHC HEAD stopped building the diagrams library. Several prerequisite libs also fail to compile. A specific error message appears in an attoparsec issue <https://github.com/bos/attoparsec/issues/67>, for which I have submitted a workaround. But as Herbert cautiously points out, this could be a recent GHC bug surfacing. The symptoms of the bug seem to be that GHC complains about the usage of (~) type equality operation, but there is no reference to that type operator in the source code. To work around the problem it suffices to add -XGADTs or -XTypeFamilies. Does this ring any bells? Can automatized tests catch such things in the future? Cheers, Gabor

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Re: GHC/cabal release procedures, and Stackage
by Joachim Breitner 11 Jun '14

11 Jun '14

Hi Michael, Am Samstag, den 07.06.2014, 21:06 +0300 schrieb Michael Snoyman: > If there was a daily snapshot build, I would be happy to set up some > kind of regular process to download that snapshot and do a Stackage > run on it. I'm currently blocked on this kind of activity, since I > can't get a successful GHC 7.8 build due to my system using the Gold > linker. That would be great, both for GHC and for people who want to have their packages work on GHC HEAD without manually monitoring it. There is http://deb.haskell.org/ which should produce daily debian packages for Debian wheezy. I guess if you are building on that platform, such packages are easiest to use (as you need no particular tooling to update and install). http://deb.haskell.org/dailies/latest/ is currently lagging due to temporary full disk, but I hope that by tomorrow, we have a new build. There used to be daily snapshot builds at http://darcs.haskell.org/ghcBuilder/uploads/ but that is defuct (Can someone remove the link from http://www.haskell.org/ghc/download) I wonder if the “new” builder infrastructure at http://haskell.inf.elte.hu/builders/ assembles the snapshots somewhere, then you can use them. Or you can build GHC yourself as part of the stackage run. Greetings, Joachim -- Joachim “nomeata” Breitner mail(a)joachim-breitner.de • http://www.joachim-breitner.de/ Jabber: nomeata(a)joachim-breitner.de • GPG-Key: 0xF0FBF51F Debian Developer: nomeata(a)debian.org

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Re: Windows breakage (+patch)
by Sergei Trofimovich 11 Jun '14

11 Jun '14

On Wed, 11 Jun 2014 21:35:57 +0300 Sergei Trofimovich <slyfox(a)gentoo.org> wrote: > On Wed, 11 Jun 2014 08:18:30 +0000 > Simon Peyton Jones <simonpj(a)microsoft.com> wrote: > > > Stefan, Guys > > This commit breaks the Windows build (ie my laptop) > > > > commit 9fd507e5758f4141ac2619f0db57136bcab035c6 > > > > Author: Sergei Trofimovich <slyfox(a)gentoo.org> > > > > Date: Fri May 23 23:58:06 2014 +0300 > > > > > > > > Raise exceptions when blocked in bad FDs (fixes Trac #4934) > > The breakage is this: > > > > C:/code/HEAD/rts/dist/build/libHSrts.a(RtsStartup.o):RtsStartup.c:(.text+0x2aa): undefined reference to `base_GHCziEventziThread_blockedOnBadFD_closure' > > The reason is, I think that that this line in RtsStartup.c should be inside the guard #ifndef mingw32_HOST_OS > > > > getStablePtr((StgPtr)blockedOnBadFD_closure); > > I'd do that myself but I am not confident that the fix is correct; and I would like to add a comment to explain why the getStablePtr is non-windows-only. > > Can someone do this, please? > > Oh, I've missed the fact GHC.Event.Thread in a non-windows thing. > The whole patch was for posix-only platform, but i tried to export > that exception for all platforms. > > CCed Simon M. > > There is 2 routes: > a) move an exception a common module to all platforms. > For example to Foreign.C.Error (I've started to prepare a patch) To avoid import loops and make things clear I've moved it to GHC.Exception.RTS (other from-rts exceptions can be pushded there as well) Patch is in attach. Please review. Thank you! -- Sergei

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Re: [commit: ghc] master: Update mod73 test output (1178fa4)
by Richard Eisenberg 11 Jun '14

11 Jun '14

This test case is failing on my machine, too. Is it perhaps possible to sort the output to avoid these wibbles? I looked at the code and it's not immediately obvious to me the best place to do this... Thanks, Richard On Jun 6, 2014, at 10:09 AM, git(a)ghc.haskell.org wrote: > Repository : ssh://git@git.haskell.org/ghc > > On branch : master > Link : http://ghc.haskell.org/trac/ghc/changeset/1178fa4ada1ac054976f3abb2e303ad42… > >> --------------------------------------------------------------- > > commit 1178fa4ada1ac054976f3abb2e303ad42653e303 > Author: Joachim Breitner <mail(a)joachim-breitner.de> > Date: Fri Jun 6 15:03:36 2014 +0200 > > Update mod73 test output > > to what I observe on travis and on my validate machine, even though my > local tree produces the previous output. > > >> --------------------------------------------------------------- > > 1178fa4ada1ac054976f3abb2e303ad42653e303 > testsuite/tests/module/mod73.stderr | 4 ++-- > 1 file changed, 2 insertions(+), 2 deletions(-) > > diff --git a/testsuite/tests/module/mod73.stderr b/testsuite/tests/module/mod73.stderr > index d19a032..576b0e3 100644 > --- a/testsuite/tests/module/mod73.stderr > +++ b/testsuite/tests/module/mod73.stderr > @@ -2,6 +2,6 @@ > mod73.hs:3:7: > Not in scope: ‘Prelude.g’ > Perhaps you meant one of these: > - data constructor ‘Prelude.GT’ (imported from Prelude), > + data constructor ‘Prelude.LT’ (imported from Prelude), > data constructor ‘Prelude.EQ’ (imported from Prelude), > - data constructor ‘Prelude.LT’ (imported from Prelude) > + data constructor ‘Prelude.GT’ (imported from Prelude) > > _______________________________________________ > ghc-commits mailing list > ghc-commits(a)haskell.org > http://www.haskell.org/mailman/listinfo/ghc-commits >

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Hashes for download files
by Yitzchak Gale 11 Jun '14

11 Jun '14

Perhaps it would be a good idea to post hashes on the download site for each downloadable file, to make it easier to verify that you have the genuine article. Thanks, Yitz

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