http://blog.gmane.org/gmane.comp.lang.haskell.glasgow.user hourly 1 1901-01-01T00:00+00:00 http://gmane.org/img/gmane-25t.png http://gmane.org http://comments.gmane.org/gmane.comp.lang.haskell.glasgow.user/22124 <pre>Hi folks. I have a piece of Haskell code that's been laying around on my computer for about a year, and I recently decided to dust it off. The problem is that it used to work fine, but in the interim (in which I both upgraded OS versions/GHC versions and went from 32 bit to 64 bit) the code stopped working reliably. It tends to work OK for small data sets, but with larger data sets it exhibits one of three bad behaviors: 1) A segfault, 2) An "Error in array index" error, or 3) The following runtime error: internal error: evacuate: strange closure type 5060208 (GHC version 7.0.3 for x86_64_unknown_linux) Please report this as a GHC bug: http://www.haskell.org/ghc/reportabug Aborted It complies OK, although with optimization turned on it gives me a "has one call pattern, but the limit is 0" error, but my understanding is that this shouldn't really be an issue. I'd like to figure out what this issue is, but while I understand a bit about the language itself, w</pre> Mark Conway Wirt 2012-05-25T13:33:45 http://comments.gmane.org/gmane.comp.lang.haskell.glasgow.user/22121 <pre>Hi, I am with ghc 7.4.1. For some reason I need a totally static linked compilation to my code. But it failed when linking some packages came with ghc, like unix-2.5.1.0. Trying to rebuild ghc to make all staticly, but failed to find args like this when configuring ghc. What should I do? </pre> Magicloud Magiclouds 2012-05-21T07:47:22 http://comments.gmane.org/gmane.comp.lang.haskell.glasgow.user/22116 <pre>I built GHC 7.2.2 on a LINUX box running RHEL 3. When compiling a package using this GHC it is trying to invoke ar thus: execve("/usr/bin/ar", ["/usr/bin/ar", "-r", "-c", "dist/build/libHSregex-base-0.93."..., "dist/build/Text/Regex/Base.o", "dist/build/Text/Regex/Base/Regex"..., "dist/build/Text/Regex/Base/Conte"..., "dist/build/Text/Regex/Base/Impl."...], [/* 45 vars */]) = 0 My version of ar does not like being invoked as "/usr/bin/ar -r -c lib.a file file file...", it complains that the .a file is missing. I believe it should be "/usr/bin/ar rc lib.a file file file...". This appears to originate in Distribution.Simple.Program.Ar. Can someone tell me what is going on here? Joe Buehler </pre> Joe Buehler 2012-05-18T19:20:07 http://comments.gmane.org/gmane.comp.lang.haskell.glasgow.user/22110 <pre>Hi, I'm experimenting with a preprocessor to automatically generate test drivers[1]. The result depends on the existence of other files on the disk. When files are added or removed, the test driver has to be regenerated. Ideally ghc would just always recompile that single file (akin to make's .PHONY), and it should work with ghci's :reload and with cabal. I tried to touch the file within the preprocessor, but this does not work. It seems, that GHC checks the modification time only after preprocessing. Any ideas how to tackle this? Cheers, Simon [1] https://github.com/sol/hspec-discover </pre> Simon Hengel 2012-05-17T08:58:02 http://comments.gmane.org/gmane.comp.lang.haskell.glasgow.user/22109 <pre>I am planning on doing this early next week, probably in two phases. As part of the import process, github will generate a *lot* of notification emails. I'm afraid there is nothing I can do to stem the tide, as github does not provide a mechanism to suppress these. If you have a github account, please brace yourself. _______________________________________________ Glasgow-haskell-users mailing list Glasgow-haskell-users&lt; at &gt;haskell.org http://www.haskell.org/mailman/listinfo/glasgow-haskell-users </pre> Bryan O'Sullivan 2012-05-17T03:45:03 http://comments.gmane.org/gmane.comp.lang.haskell.glasgow.user/22108 <pre> We are pleased to announce the first release candidate for GHC 7.4.2: http://www.haskell.org/ghc/dist/7.4.2-rc1/ This includes the source tarball, installers for OS X and Windows, and bindists for amd64/Linux, i386/Linux, amd64/FreeBSD and i386/FreeBSD. Please test as much as possible; bugs are much cheaper if we find them before the release! Thanks Ian, on behalf of the GHC team </pre> Ian Lynagh 2012-05-16T10:05:00 http://comments.gmane.org/gmane.comp.lang.haskell.glasgow.user/22107 <pre>We just released version 0.12 of Data.Array.Accelerate, the GPGPU[1] library for Haskell: http://justtesting.org/gpu-accelerated-array-computations-in-haskell This is a beta release. The library is not perfect, but it is definitely usable, and we are looking for early adopters. Manuel [1] Currently only NVIDIA GPUs are supported via NVIDIA's CUDA framework. </pre> Manuel M T Chakravarty 2012-05-14T07:50:40 http://comments.gmane.org/gmane.comp.lang.haskell.glasgow.user/22103 <pre>Hello glasgow-haskell-users, the one thing that users of my program asked most is the Win64 support: http://code.google.com/p/freearc/issues/list . we have waited for a several years, but it's still not in GHC, so i want to know at least: why it's not going forward? can we have unregisterized build at least? </pre> Bulat Ziganshin 2012-05-09T14:54:48 http://comments.gmane.org/gmane.comp.lang.haskell.glasgow.user/22096 <pre>LS. I have a very memory intensive application. It seems that the timing of my application depend very much on the precise setting of -H...M in the runtime system (-H2000M seems to work best, computation time becomes a third of what I get when I pass no -H option). I conjecture that this good behaviour is the result of gc happening at the right time. So I wondered: if I can one when is the right time, is it possible then to trigger GC explicitly from within the Haskell code? best, Jur </pre> Jurriaan Hage 2012-05-07T13:33:52 http://comments.gmane.org/gmane.comp.lang.haskell.glasgow.user/22089 <pre>Hello, Before I turn the following into a ticket I want to ask if I miss something obvious: When I run the following program: ------------------------------------------------- import Prelude hiding (catch) import Control.Exception import Control.Concurrent main :: IO () main = do mv &lt;- newEmptyMVar _ &lt;- forkIO $ do catch action (\e -&gt; putStrLn $ "I solved the Halting Problem: " ++ show (e :: SomeException)) putStrLn "putting MVar..." putMVar mv () putStrLn "putted MVar" takeMVar mv action :: IO () action = let x = x in x ------------------------------------------------- I get the output: $ ghc --make Loop.hs -o loop -O2 -fforce-recomp &amp;&amp; ./loop [1 of 1] Compiling Main ( Loop.hs, Loop.o ) Linking loop ... loop: thread blocked indefinitely in an MVar operation I solved the Halting Problem: &lt;&lt;loop&gt;&gt; putting MVar... putted MVar As can be seen, the putMVar is executed successfully. So why do I get the mes</pre> Bas van Dijk 2012-05-03T15:10:38 http://comments.gmane.org/gmane.comp.lang.haskell.glasgow.user/22088 <pre>Hi, I am currently trying to get my ADPfusion library to optimize code using ghc-head (same thing described below happens with 7.4.1). Using ghc-7.2.2, both test programs (Nussinov78 and RNAFold) optimize well, the performance is close to C and ghc-core shows good code. This is mostly to say that optimization using ghc-7.2.2 is not an accident but works reliably. Unfortunately, with ghc-head it seems that constructor specialization does not happen. I see a lot of "case x of, Left -&gt; ..., Right -&gt; ..." and "case x of, Yield -&gt; ..." which leads to really bad (slow) code. As there are some discussions going on regarding the optimizer not optimizing (like the ticks exhausted [1] one), are there other changes in the optimizer that could affect it? spec-constr-count / threshold, simplifier phases, simpl-tick-factor, no-liberate-case I have tried... Thanks, Christian PS: This is a ask-first-try-to-find-a-simple-example-later mail ;-) [1] http://hackage.haskell.org/trac/ghc/ticket/5539 _____________________</pre> Christian Höner zu Siederdissen 2012-04-30T22:11:07 http://comments.gmane.org/gmane.comp.lang.haskell.glasgow.user/22014 <pre>Hi, I have been struggling to build ghc74 on ARM (ideally with llvm3) on Fedora 18 (the current development tree). After applying 4 recent ARM patches from Debian the ghc-7.4.1 build gets to: : "inplace/bin/ghc-stage1" -H32m -O -package-name base-4.5.0.0 -hide-all-packages -i -ilibraries/base/. -ilibraries/base/dist-install/build -ilibraries/base/dist-install/build/autogen -Ilibraries/base/dist-install/build -Ilibraries/base/dist-install/build/autogen -Ilibraries/base/include -optP-DOPTIMISE_INTEGER_GCD_LCM -optP-include -optPlibraries/base/dist-install/build/autogen/cabal_macros.h -package ghc-prim-0.2.0.0 -package integer-gmp-0.4.0.0 -package rts-1.0 -package-name base -XHaskell98 -XCPP -O2 -no-user-package-conf -rtsopts -odir libraries/base/dist-install/build -hidir libraries/base/dist-install/build -stubdir libraries/base/dist-install/build -hisuf hi -osuf o -hcsuf hc -c libraries/base/dist-install/build/GHC/Event/Clock.hs -o libraries/base/dist-install/build/GHC/Event/Clock.o [parallel bui</pre> Jens Petersen 2012-04-22T08:19:57 http://comments.gmane.org/gmane.comp.lang.haskell.glasgow.user/22009 <pre>I would like to default IsString to use the Text instance to avoid ambiguous type errors. I see defaulting capability is available for Num. Is there any way to do this for IsString? Thanks, Greg Weber </pre> Greg Weber 2012-04-22T00:20:52 http://comments.gmane.org/gmane.comp.lang.haskell.glasgow.user/22007 <pre>I've isolated the below small piece of code that is giving me a stack overflow. I'm kind of at a loss as has to fix, or even find what is happening here. (The real program is reading the data from a file, and doing something more complex with it). I'm not even sure how to work around this issue. It fails for me when given an argument of 1000000. Any ideas? I'm running 7.0.4, but I've tried this with ghc 6.12.3, and 7.4.1. Thanks, David ---------------------------------------------------------------------- import Control.Applicative import Control.Monad import Data.Binary import Data.Binary.Put import Data.Binary.Get import Data.List import Data.Word import System.Environment putValues :: [Int] -&gt; Put putValues vals = mapM_ (putWord32le . fromIntegral) vals getValues :: Int -&gt; Get [Int] getValues count = replicateM count (fromIntegral &lt;$&gt; getWord32le) goofySum :: Int -&gt; Int goofySum count = let block = runPut $ putValues [1 .. count] in foldl' max 0 $ runGet (getValues count) block main </pre> David Brown 2012-04-21T18:21:02 http://comments.gmane.org/gmane.comp.lang.haskell.glasgow.user/22006 <pre>Hello, To experiment with some of GHC's new features in HEAD, I have started ported part of the Prelude from values and functions to types and constraints. For example: comparing lists. instance Compare '[] '[] EQ instance Compare '[] (x ': xs) LT instance Compare (x ': xs) '[] GT instance (Compare x y o, Case o [ EQ --&gt; Compare xs ys r, o --&gt; o ~ r ]) =&gt; Compare (x ': xs) (y ': ys) r Prelude.Type&gt; T :: (Compare '[I 1, I 2] '[I 1, I 3] a) =&gt; T a LT Sometimes I get nice error messages. Prelude.Type&gt; T :: If (I 1 == I 2) (a ~ "hello") (a ~ 3) =&gt; T a Kind mis-match The left argument of the equality predicate had kind `Symbol', but `3' has kind `Nat' But often GHC refuses to type large constraints when there are too many constraint kinds and free variables. It also gets confused if I pretend to use higher-order kinds. instance ((a &gt;&gt;= Const b) c) =&gt; (a &gt;&gt; b) c Kind mis-match The first argument of `&gt;&gt;' should have kind `k0 k1', but `a' has kind `k0 k1</pre> Etienne Laurin 2012-04-20T23:43:40 http://comments.gmane.org/gmane.comp.lang.haskell.glasgow.user/22003 <pre>Hi, Building GHC HEAD (git HEAD SHA1 = 88f476b98709731d997ab57612cce4753cb65a0a) this morning, I've encountered 2 build failures that seem to be a result of some recent changes in the past day or two. If I build a clean repository with `make -j13` on my 12 core machine, I get: ------------------------------------------------------------------------------ compiler/hsSyn/Convert.lhs:178:30: `td_fvs' is not a (visible) field of constructor `TyData' compiler/hsSyn/Convert.lhs:190:31: `td_fvs' is not a (visible) field of constructor `TyData' make[1]: *** [compiler/stage2/build/Convert.o] Error 1 make[1]: *** Waiting for unfinished jobs.... --------------------------------------------------------------------------- However, reinvoking `make` with no parallelism and attempting to continue the build (there's no race condition obviously, I was just curious,) I get another (possibly related) build failure as well: --------------------------------------------------------------------------- compiler/deSuga</pre> Austin Seipp 2012-04-20T17:11:49 http://comments.gmane.org/gmane.comp.lang.haskell.glasgow.user/21997 <pre>Hello GHC Devs, One issue that's been bothering me when writing Haskell programs meant to be long-running processes performing computations on external input-data in terms of an event/request-loop (think web-services, SQL-servers, or REPLs), that it is desirable to be able to limit resource-usage and be able to "contain" the effects of computations which exhausts the resource-limits (i.e. w/o crashing and burning the whole process) For the time-dimension, I'm already using functions such as System.Timeout.timeout which I can use to make sure that even a (forced) pure computation doesn't require (significantly) more wall-clock time than I expect it to. But I'm missing a similar facility for constraining the space-dimension. In some other languages such as C, I have (more or less) the ability to check for /local/ out-of-memory conditions (e.g. by checking the return value of e.g. malloc(3) for heap-allocations, or by handling an OOM exception), rollback the computation, and be able to skip to the next compu</pre> Herbert Valerio Riedel 2012-04-19T10:45:06 http://comments.gmane.org/gmane.comp.lang.haskell.glasgow.user/21986 <pre>Dear all, from the RTS option -s I get : INIT time 0.00s ( 0.00s elapsed) MUT time 329.99s (940.55s elapsed) GC time 745.91s (751.51s elapsed) RP time 765.76s (767.76s elapsed) PROF time 359.95s (362.12s elapsed) EXIT time 0.00s ( 0.00s elapsed) I can guess what most components mean, but do not know what RP stands for. I also could not find this information in the GHC documentation that is online. Can anyone tell me? Jur </pre> Jurriaan Hage 2012-04-17T11:22:31 http://comments.gmane.org/gmane.comp.lang.haskell.glasgow.user/21984 <pre>I'm simulating skolem variables in order to fake universal quantification in constraints via unsafeCoerce. http://hpaste.org/67121 I'm not familiar with various categories of types from the run-time's perspective, but I'd be surprised if there were NOT a way to use this code to create run-time errors. Is there a way to make it safer? Perhaps by making Skolem act more like GHC's Any type? Or perhaps like the -&gt; type? I'd like to learn about the varieties of types from the run-time's perspective. I know Dimitrios Vytiniotis is trying to implement these legitimately in GHC, but I don't know much about that project's status, nor any documentation indicating how to try it out in GHC HEAD (e.g. what's the syntax?). Is there a page on the GHC wiki or something to check that sort of thing? I wonder how far this Forall_S trick can take me in the interim towards Vytiniotis' objective functionality when paired with a (totally safe) class for implication. Thanks, Nick </pre> Nicolas Frisby 2012-04-16T22:57:54 http://comments.gmane.org/gmane.comp.lang.haskell.glasgow.user/21983 <pre>Hello all, I recently ran into a rather reproduceable bug where I would get this error from the event manager: /dev/null: hClose: user error (Pattern match failure in do expression at libraries/base/System/Event/Thread.hs:83:3-10) The program was doing some rather strange things: - It was running the Haskell RTS inside another system (Urweb) which was making use of pthreads, sockets, etc. - The Haskell portion was linked against the threaded RTS, and doing communication with a process. and is rather complicated (two compilers are involved). But the gist of the matter is that if I added a quick call to ensureIOManagerIsRunning after hs_init, the error went away. So, if the IO manager is not eagerly loaded at the call to hs_init, how do we decided when it should be loaded? It seems probably that we missed a case. Edward P.S. I tried reproducing on a simple test case but couldn't manage it. </pre> Edward Z. Yang 2012-04-14T03:53:32 http://comments.gmane.org/gmane.comp.lang.haskell.glasgow.user/21982 <pre>Hello GHC users. I made another proposal for records in Haskell, meant to solve just the namespace problem, and no more. http://hackage.haskell.org/trac/ghc/wiki/Records/ExplicitClassyRecords In this system, record selectors are overloaded in explicitly-user-declared type classes. Thus one can control the scope as of any other type class. Cheers, strake </pre> Matthew Farkas-Dyck 2012-04-12T03:39:45 Search the mailing list at Gmane query http://search.gmane.org/?group=$group=gmane.comp.lang.haskell.glasgow.user