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Re: wither the Platform
by Neil Mitchell 23 Mar '15

23 Mar '15

On Windows, the reason I used to use the Platform was that it came with an installed network library, and installing the network library on Windows is a real pain (and often fails). Unfortunately it was incredibly brittle, a single attempt at upgrading network from some newer package usually trashed my Haskell install and required a wipe and restart. Nowadays I use https://github.com/fpco/minghc which can actually install network, and I've had zero problems. I can get up to the platform with one invoke of cabal, and if someone decides to require a new network, it just works. I think the Platform now gives a worse user experience on Windows, so the ideas (or names) probably need migrating around. Thanks, Neil On Sun, Mar 22, 2015 at 8:47 AM, Heinrich Apfelmus <apfelmus(a)quantentunnel.de> wrote: > Mark Lentczner wrote: >> >> I'm wondering how we are all feeling about the platform these days.... >> >> I notice that in the new Haskell pages, the Platform is definitely not the >> recommended way to go: The main download pages suggests the compiler and >> base libraries as the first option - and the text for the Platform (second >> option) pretty much steers folks away from it. Of the per-OS download >> pages, only the Windows version even mentions it. >> >> Does this mean that we don't want to consider continuing with it? It is a >> lot of community effort to put out a Platform release - we shouldn't do it >> if we don't really want it. >> >> That said, I note that the other ways to "officially get" Haskell look, to >> my eye, very ad hoc. Many of the options involve multiple steps, and >> exactly what one is getting isn't clear. It hardly looks like there is now >> an "official, correct" way to setup Haskell. >> >> The Platform arose in an era before sandboxes and before curated library >> sets like Stackage and LTS. Last time we set direction was several years >> ago. These new features and development have clearly changed the landscape >> for use to reconsider what to do. >> >> >> I don't think the status quo for the Platform is now viable - mostly as >> evidenced by waning interest in maintaining it. I offer several ways we >> could proceed: >> >> *1) Abandon the Platform.* GHC is release in source and binary form. Other >> package various installers, with more or less things, for various OSes. >> >> *2) Slim the Platform.* Pare it back to GHC + base + a smaller set of >> "essential" libs + tools. Keeps a consistent build layout and installation >> mechanism for Haskell. >> >> *3) Re-conceive the Platform.* Take a very minimal install approach, >> coupled with close integration with a curated library set that makes it >> easy to have a rich canonical, stable environment. This was the core idea >> around my "GPS Haskell" thoughts from last September - but there would be >> much to work out in this direction. >> >> Thoughts? > > > Thanks a lot for your hard work on the platform! > > I myself am an avid user of the platform (OS X), because for me, it's the > easiest way to install Haskell on a new machine; I just did so the other > day. > > The only time when the platform seems to be a handicap is when a new version > of GHC is being released and I would have to update my packages. Usually, I > don't test them with the new version and rely on pull requests instead. > > > Best regards, > Heinrich Apfelmus > > -- > http://apfelmus.nfshost.com > > > _______________________________________________ > Libraries mailing list > Libraries(a)haskell.org > http://mail.haskell.org/cgi-bin/mailman/listinfo/libraries

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fast test suite failures on OS X with 7.10 RC head
by Carter Schonwald 23 Mar '15

23 Mar '15

hey all heres the results from the test suite run on a build of 7.10 head on OS X i believe that some of the test suite failures are because I set the min OS X version to 10.6 rather than 10.7, and that some are because GCC (unlike clang) doesn't support certain OS X specific things like objective C or related header files. I'll add more information as I have the time, but figured I should share this for now Unexpected results from: TEST="T10019 sigcabal01 objc-hi objcpp-hi retc001 linker_unload debug T2276_ghci T9203 T1969 T9675 T783 T5642 T6048" OVERALL SUMMARY for test run started at Sun Mar 22 14:58:07 2015 EDT 0:31:34 spent to go through 4405 total tests, which gave rise to 18027 test cases, of which 13966 were skipped 52 had missing libraries 3950 expected passes 45 expected failures 0 caused framework failures 0 unexpected passes 8 unexpected failures 6 unexpected stat failures Unexpected failures: cabal/sigcabal01 sigcabal01 [bad stderr] (normal) codeGen/should_compile debug [bad stderr] (normal) driver/objc objc-hi [exit code non-0] (normal) driver/objc objcpp-hi [exit code non-0] (normal) driver/retc001 retc001 [bad stderr] (normal) ffi/should_run T2276_ghci [bad exit code] (ghci) rts linker_unload [bad exit code] (normal) th T10019 [bad stdout] (ghci) Unexpected stat failures: perf/compiler T1969 [stat not good enough] (normal) perf/compiler T5642 [stat not good enough] (normal) perf/compiler T6048 [stat not good enough] (optasm) perf/compiler T783 [stat not good enough] (normal) perf/compiler T9675 [stat not good enough] (optasm) perf/should_run T9203 [stat too good] (normal) ~/D/r/g/testsuite (ghc-7.10|…) $ echo $MACOSX_DEPLOYMENT_TARGET 10.6

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Re: [haskell-infrastructure] wither the Platform
by Gershom B 22 Mar '15

22 Mar '15

Thanks for kicking this off Mark. Here is what I think happened. We fragmented along two lines. A) Users that sandbox and users that do not. B) Libraries that maintain HP compatibility and libraries that do not. The growth of non HP-compat libs is clearly what has driven the growth in sandboxing users. That brings us to the current situation where new users who install the platform then run into the issue hvr describes — platform-installed packages being available in sandboxes and causing trouble. However, the current solution we push to new users is lacking in certain ways. In particular, I really don’t like not providing standard binary/installers from a _single source_ across all platforms. Instead, we have installers from three sources, with the minimal windows and mac ones being from small strikeforces or individuals, but not necessarily a team where everything is documented so others can step in if someone decides to go off and surf for the rest of their life in an area with poor wi-fi, etc. Furthermore, it is _very_ important to have some community process to “bless” or suggest some set of packages from the zoo of hackage as the “typical” way to accomplish certain tasks, and I think we have been overly conservative in adding packages to the platform, probably due to the problem of pulling in unrelated dependencies, etc. This blessed set serves, among other things, as a core set of packages to advise distro managers on the baseline they should package, etc. Finally, while sandboxes seem necessary, sandboxes are a _hack_ and it would be good to provide a way for users to maintain a local db that they like and trust of a set of baseline libs while making it _easy_ to override these in individual sandboxes. Overall I tend to agree with dons’ comments on the reddit thread (http://www.reddit.com/r/haskell/comments/2zts44/wither_the_platform/cpmy54n) and think the key idea is to preserve _both_ the “one stop installer” aspect of the platform and the “blessed package set” element, but to decouple them from one another. This leads to the following proposals: 1) Reboot the HP installers for windows and mac as effectively the MinGHC and GHC For Mac OS X, working with those teams but centralizing the build/packaging knowledge and provide them all from one place. 2) For generic linux point to both ghc and cabal binaries from the core teams. 3) Continue to pick out and list a compatible, “blessed” set of libraries under the platform umbrella, but do not necessarily package them with installers. Reboot interest in expanding and curating further the list of libraries across a wider range of application domains. 4) Improve sandbox tooling so that it is easy to exclude packages from the main database when building within sandboxes. And of these I have one outstanding question — while MinGHC makes it easy to install network directly on windows machines, what does it do about the GL libraries? Or for getting a windows GHC with graphics, does the current platform build remain a better solution? If we can’t solve that, then the MinGHC approach doesn’t yet provide a strictly better solution. Cheers, Gershom On March 22, 2015 at 10:24:09 AM, Yitzchak Gale (gale(a)sefer.org) wrote: > Mark Lentczner wrote: > > 1) Abandon the Platform… > > > > 2) Slim the Platform. Pare it back to GHC + base + a smaller set of > > "essential" libs + tools. Keeps a consistent build layout and installation > > mechanism for Haskell. > > > > 3) Re-conceive the Platform. Take a very minimal install approach, coupled > > with close integration with a curated library set that makes it easy to have > > a rich canonical, stable environment. This was the core idea around my "GPS > > Haskell" thoughts from last September - but there would be much to work out > > in this direction. > > I vote for (3) but in a way that it would *not* be much work. > We should definitely do the Platform, but with much *less* work. > > The most important reason we need the Platform is as > a default selection of quality basic libraries. We should not abandon > that concept. Curated package sets do not replace that - the > Platform is not just packages that build together. Nor do OS > packagers. The platform is a community-wide set of basic default > packages that are mature, well tested, all work together well, > and stable. > > The second most important role of the Platform is a web site > where you can get a clear picture of how to download and install > a default Haskell installation for your platform, and a simple view > of where we are in the parade of releases. That should also continue. > > The hardest work of the Platform was its role as a way to bootstrap a > Haskell installation. That is what made it so hard for HP to keep up > with GHC releases, and what consequently gave people the impression > that HP is always old. That work doesn't need to be done as part of the > Platform anymore. We should leverage other good work people are > doing to create installers, and stop doing it as part of the HP process. > > The most important part of an HP release should be a cabal package > that provides the packages in the platform, at the right versions, with > a specification of the recommended GHC version as a pre-requisite. > > Perhaps we can also provide an HP-branded slick installer for some > platforms that does everything in one click, built as a thin wrapper of > some existing installer. But that should not delay the official release > of an HP version. It's just a nice-to-have extra. > > Once we pare down the work needed for an HP release, we should > release new versions of HP quite often - *more* often than GHC > releases, not less often. > > Another thing we should fix is the (now false) impression that HP > gets in the way of installing other packages and versions due to > cabal hell. We should make "require-sandbox" the default setting > in the cabal config file. I would go further - I would add a cabal > feature to create a sandbox automatically unless "--user" or > "--global" is specified explicitly. I would make "foo installed" a > default constraint (that is easy to override) for all platform packages, > which solves virtually all cabal hell problems (assuming you are > using a sandbox) and will not keep things old if we release often. > > Thanks, > Yitz > _______________________________________________ > haskell-infrastructure mailing list > haskell-infrastructure(a)community.galois.com > http://community.galois.com/mailman/listinfo/haskell-infrastructure >

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can't run validate on OS X for 7.10 head branch!
by Carter Schonwald 22 Mar '15

22 Mar '15

hey everyone! error: unknown warning option '-Werror=unused-but-set-variable'; did you mean '-Werror=unused-const-variable'? [-Werror,-Wunknown-warning-option] is the key bit, seems like apple clang bundled with xcode 6 doesn't have that option thoughts? (do we need to do some auto conf magic to support more clang variants?) this gist provides a bit more context https://gist.github.com/cartazio/ac04ab8048c9f7577d3d thanks! -Carter

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Re: wither the Platform
by Mark Lentczner 21 Mar '15

21 Mar '15

Eeek! I really really did mean to make the subject *whither*, not *wither!*

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GHC Trac
by Simon Peyton Jones 21 Mar '15

21 Mar '15

Is it just me, or is GHC's Trac super-slow (again)? Actually it's not just slow but offline from where I am. Simon

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RE: Shake fails test with GHC 7.10 RC3
by Simon Peyton Jones 21 Mar '15

21 Mar '15

| FWIW, I've been noodling over this today since I saw this email, and | sitting down, I think this may be a blocker worth holding up for after | thinking about it. At least, it is until we can quantify how much it | might bite (can we find a workaround? How often does it hit in | practice?) I'm reluctant to delay 7.10 further. I'm sure there are other bugs, and we'll want 7.10.2 before too long. But we won't find them until we push it out. The danger is that we stay in about-to-release mode for ages, and that holds everyone up. We've had three release candidates out over a period of months and Neil seems to be the only one who has tripped over it. I think it'd be better to push it out. (We planned to do so today!) What do others think? Simon | -----Original Message----- | From: mad.one(a)gmail.com [mailto:mad.one@gmail.com] On Behalf Of Austin | Seipp | Sent: 20 March 2015 22:48 | To: Herbert Valerio Riedel | Cc: Simon Peyton Jones; Austin Seipp | Subject: Re: Shake fails test with GHC 7.10 RC3 | | FWIW, I've been noodling over this today since I saw this email, and | sitting down, I think this may be a blocker worth holding up for after | thinking about it. At least, it is until we can quantify how much it | might bite (can we find a workaround? How often does it hit in | practice?) | | I'm testing Iavor's patches that he wanted in at the last minute (I'm | really hesitant for that, since we could break something), so we've | got some time, but I'd like to at least narrow this down a bit more. | | On Fri, Mar 20, 2015 at 12:37 PM, Herbert Valerio Riedel | <hvriedel(a)gmail.com> wrote: | > | > ...does this in any way affect today's GHC 7.10.1 release? I.e. is this | > blocking the release? | > | > | > On 2015-03-20 at 18:19:09 +0100, Simon Peyton Jones wrote: | >> Neil | >> | >> Could you open a ticket for this, and attach the info to it? Lots of | useful info in this thread, but may get lost. | >> | >> Re empty cases, see Note [Empty case alternatives] in CoreSyn. "A | >> case expression can have empty alternatives if (and only if) the | >> scrutinee is bound to raise an exception or diverge." | >> | >> So yes, case (\_ -> ...) of {} is definitely wrong. Could someone | >> extend Core Lint to check for this? The function to call is | >> exprIsHNF: if we have | >> case e of {} | >> then exprIsHNF should never return True. | >> | >> That is a powerful clue, and adding it to Lint will nail the moment at | which it first happens. Good progress. | >> | >> (I'd do it myself but I'm struggling with backlog, and only have 3 | days left before going on holiday for 10 days.) | >> | >> Simon | >> | >> | -----Original Message----- | >> | From: Neil Mitchell [mailto:ndmitchell@gmail.com] | >> | Sent: 20 March 2015 16:57 | >> | To: Carter Schonwald | >> | Cc: Simon Peyton Jones; ghc-devs(a)haskell.org | >> | Subject: Re: Shake fails test with GHC 7.10 RC3 | >> | | >> | > do you use a deepSeq when catching errors from a pure | computation? Or | >> | > is it in a context where you know the value should be treated | strictly? | >> | | >> | The computation is essentially (error "here" :: IO ()), so the IO | monadic | >> | binding should force the exception. In the full source code to | Shake it's | >> | actually in ContT/ReaderT/IO, but a modification to insert liftIO | (if | >> | done in exactly the right way) gives the same result. That | simplified | >> | code is at http://community.haskell.org/~ndm/temp/src.zip | >> | (to run, compile with the logic from | >> | https://github.com/ndmitchell/shake/blob/master/.ghci :benchmark, | then | >> | run "main oracle test"). | >> | | >> | > https://github.com/ndmitchell/shake/issues/216 seems to be the | ticket | >> | > in question | >> | | >> | That is the ticket. The test that is failing is the "oracle" | >> | (Test.Oracle) test suite, and you can see full logs of both success | and | >> | failure at Travis: | >> | https://travis-ci.org/ndmitchell/shake/builds/54748475 . Note that | it | >> | succeeds on GHC 7.2, 7.4, 7.6 and 7.8, but fails on GHC 7.10 RC3 | and GHC | >> | Head. | >> | | >> | Alas, the actual error is coming from deep in the middle of Shake, | >> | specifically this line: | >> | | https://github.com/ndmitchell/shake/blob/master/src/Development/Shake/Cor | >> | e.hs#L329 | >> | | >> | Thinking some more on what I saw, my best guess is that: | >> | | >> | case (\_ -> ...) of {} | >> | | >> | Is a fatal error in GHC. I am guessing that {} means there are no | >> | alternatives because GHC managed to show that the scrutinee throws | an | >> | exception. In addition, evaluating a literal lambda to WHNF will | not | >> | throw an exception, so you have a contradiction. | >> | | >> | Making increasingly wild speculative guesses, I could imagine this | code | >> | compiling to CMM that just fell off the end of a basic block, | arriving at | >> | the next statement of supposedly unconnected code. That actually | matches | >> | what I'm seeing - I have the exception, using print I can see I am | at the | >> | line before, and that I never get to the line after, but pop up | somewhere | >> | nearby and continue onwards seemingly ignoring the exception ever | >> | happened. | >> | | >> | If someone can confirm the above pattern of Core is always illegal | and | >> | always indicates a GHC error then I can reduce the test case driven | >> | purely by the Core, which would be far easier - at the moment Shake | >> | passes through these routines several times to set things up, | making it | >> | harder to simplify them too much without changing the preparation | steps. | >> | | >> | Thanks, Neil | >> | | >> | | >> | >> | >> | >> On Fri, Mar 20, 2015 at 12:01 AM, Neil Mitchell | >> | >> <ndmitchell(a)gmail.com> | >> | >> wrote: | >> | >> > More delving later, it seems the incorrect optimized version | has | >> | >> > been turned into: | >> | >> > | >> | >> > case (\ _ [Occ=Dead, OS=OneShot] -> error "here") of _ | [Occ=Dead] | >> | >> > {} | >> | >> > | >> | >> > While the working one has been turned into: | >> | >> > | >> | >> > errorFunc argument realWorldToken | >> | >> > | >> | >> > where errorFunc _ = error "here" | >> | >> > | >> | >> > I'm not familiar with case ... of _ {} - what does it mean | when | >> | >> > there are no alternatives to the case? And why isn't case on a | >> | >> > literal lambda optimised out? Is it the OneShot annotation | (perhaps | >> | >> > coming from the state hack?) | >> | >> > | >> | >> > The full trace is at | >> | >> > https://gist.github.com/ndmitchell/b222e04eb0c3a397c758. I've | >> | >> > uploaded bad (optimises the error out) and good (works as | expected) | >> | >> > versions of the Core. The summary files are the subexpression | that | >> | >> > changed making a single difference (moving a monomorphic | NOINLINE | >> | >> > function from one module to another) plus the handful of | functions | >> | >> > they depend on, which I've reformatted/inlined/simplified to | produce | >> | the expressions above. | >> | >> > The full versions are the entire -ddump-simpl output from | about | >> | >> > halfway through the build, starting when the differences occur | - | >> | >> > let me know if you need further back. The dodgy function is | "exec". | >> | >> > | >> | >> > Thanks, Neil | >> | >> > | >> | >> > On Thu, Mar 19, 2015 at 11:07 PM, Neil Mitchell | >> | >> > <ndmitchell(a)gmail.com> | >> | >> > wrote: | >> | >> >> Herbert, thanks for the list of patches, nothing obvious | there - | >> | >> >> my best guess is it's something incredibly sensitive and it | only | >> | >> >> needs the tiniest change anywhere to make it happen. Things | like | >> | >> >> moving NOINLINE monomorphic-type definitions from one module | to | >> | >> >> another are causing the bug to appear/disappear, which isn't | what | >> | I'd expect. | >> | >> >> | >> | >> >> Simon, changing from error to error in IO causes the bug to | >> | >> >> disappear, but then so do most things. The error return type | is | >> | >> >> type IO (), so I suspect that forces it to be raised at the | right | >> | >> >> place - but it's certainly one of the possibilities for what | is | >> | >> >> going wrong. Diffing the Core is a great idea. | >> | >> >> | >> | >> >> I'll keep reducing and see what I get to. Given the | sensitivity of | >> | >> >> the bug, I'm sure a NOINLINE on an out-of-the-way function | will | >> | >> >> make it go away, so I can easily fix Shake itself - so I'm | more | >> | >> >> tracking it down from the point of GHC now. | >> | >> >> | >> | >> >> Thanks, Neil | >> | >> >> | >> | >> >> | >> | >> >> On Wed, Mar 18, 2015 at 5:04 PM, Simon Peyton Jones | >> | >> >> <simonpj(a)microsoft.com> wrote: | >> | >> >>> I'm really sorry but I can't think of anything. Sounds | horrible. | >> | >> >>> | >> | >> >>> If you throw exceptions using 'error' (not in IO), then you | are | >> | >> >>> of course vulnerable to strictness changes. If the thing | isn't | >> | >> >>> actually evaluated inside the catch block, you won't see the | >> | >> >>> exception. But I'm sure you've thought of that. | >> | >> >>> | >> | >> >>> I'd experiment with one of the smaller changes you describe, | such | >> | >> >>> as adding a putStrLn, and comparing Core, before and after. | >> | >> >>> Switching off -O will make a huge difference, so hard to | compare. | >> | >> >>> Turning off the state hack will have a more global effect. | But | >> | >> >>> the other changes sound more pin-point and hence the | differences | >> | will be smaller. | >> | >> >>> | >> | >> >>> Simon | >> | >> >>> | >> | >> >>> | -----Original Message----- | >> | >> >>> | From: ghc-devs [mailto:ghc-devs-bounces@haskell.org] On | Behalf | >> | >> >>> | Of | >> | >> >>> Neil | >> | >> >>> | Mitchell | >> | >> >>> | Sent: 18 March 2015 15:33 | >> | >> >>> | To: ghc-devs(a)haskell.org | >> | >> >>> | Subject: Shake fails test with GHC 7.10 RC3 | >> | >> >>> | | >> | >> >>> | Hi, | >> | >> >>> | | >> | >> >>> | Testing GHC 7.10 RC3 I've found a bug where Shake seems | to | >> | >> >>> | catch | >> | >> >>> the | >> | >> >>> | wrong exception in the wrong place. It's only hit by one | of my | >> | >> >>> tests, | >> | >> >>> | and I've managed to isolate it to a fragment of code with | no | >> | >> >>> | unsafePerformIO, that throws exceptions using error (so | not in | >> | >> >>> | IO), | >> | >> >>> and | >> | >> >>> | operates in IO. Turning off the stack hack makes the bug | go | >> | >> >>> | away, | >> | >> >>> but | >> | >> >>> | then so does -O0, marking one of the functions it calls | >> | >> >>> | NOINLINE, | >> | >> >>> or | >> | >> >>> | moving an INLINE function it calls to a different module, | or | >> | >> >>> | adding | >> | >> >>> a | >> | >> >>> | putStrLn under a catch block - it's very sensitive to the | >> | >> >>> | exact conditions. This test and this exact code worked | fine | >> | >> >>> | with GHC 7.10 RC2. | >> | >> >>> | | >> | >> >>> | I was wondering if there have been any state hack related | >> | >> >>> | changes | >> | >> >>> or | >> | >> >>> | other potentially dangerous optimisation changes since | RC2? | >> | >> >>> | I'll continue to try reducing the bug, but it's somewhat | >> | >> >>> | difficult as | >> | >> >>> the | >> | >> >>> | larger system is quite big, and the code is very | sensitive. | >> | >> >>> | | >> | >> >>> | Thanks, Neil | >> | >> >>> | _______________________________________________ | >> | >> >>> | ghc-devs mailing list | >> | >> >>> | ghc-devs(a)haskell.org | >> | >> >>> | http://mail.haskell.org/cgi-bin/mailman/listinfo/ghc-devs | >> | >> > | >> | >> > On Thu, Mar 19, 2015 at 11:24 PM, Simon Peyton Jones | >> | >> > <simonpj(a)microsoft.com> wrote: | >> | >> >> Thanks! I think a -ddump-simpl before and after the smallest | >> | >> >> change the makes the difference would be illuminating. | >> | >> >> | >> | >> >> Simon | >> | >> >> | >> | >> >> | -----Original Message----- | >> | >> >> | From: Neil Mitchell [mailto:ndmitchell@gmail.com] | >> | >> >> | Sent: 19 March 2015 23:07 | >> | >> >> | To: Simon Peyton Jones | >> | >> >> | Cc: ghc-devs(a)haskell.org | >> | >> >> | Subject: Re: Shake fails test with GHC 7.10 RC3 | >> | >> >> | | >> | >> >> | Herbert, thanks for the list of patches, nothing obvious | there - | >> | >> >> | my best guess is it's something incredibly sensitive and it | only | >> | >> >> | needs the tiniest change anywhere to make it happen. Things | like | >> | >> >> | moving NOINLINE monomorphic-type definitions from one | module to | >> | >> >> | another are causing the bug to appear/disappear, which | isn't what | >> | I'd expect. | >> | >> >> | | >> | >> >> | Simon, changing from error to error in IO causes the bug to | >> | >> >> disappear, | >> | >> >> | but then so do most things. The error return type is type | IO (), | >> | >> >> | so I suspect that forces it to be raised at the right place | - | >> | >> >> | but it's certainly one of the possibilities for what is | going | >> | >> >> | wrong. Diffing the Core is a great idea. | >> | >> >> | | >> | >> >> | I'll keep reducing and see what I get to. Given the | sensitivity | >> | >> >> | of | >> | >> >> the | >> | >> >> | bug, I'm sure a NOINLINE on an out-of-the-way function will | make | >> | >> >> | it | >> | >> >> go | >> | >> >> | away, so I can easily fix Shake itself - so I'm more | tracking it | >> | >> >> | down from the point of GHC now. | >> | >> >> | | >> | >> >> | Thanks, Neil | >> | >> >> | | >> | >> >> | | >> | >> >> | On Wed, Mar 18, 2015 at 5:04 PM, Simon Peyton Jones | >> | >> >> | <simonpj(a)microsoft.com> wrote: | >> | >> >> | > I'm really sorry but I can't think of anything. Sounds | >> | horrible. | >> | >> >> | > | >> | >> >> | > If you throw exceptions using 'error' (not in IO), then | you | >> | >> >> | > are of | >> | >> >> | course vulnerable to strictness changes. If the thing | isn't | >> | >> >> | actually evaluated inside the catch block, you won't see | the | >> | >> >> | exception. But | >> | >> >> I'm | >> | >> >> | sure you've thought of that. | >> | >> >> | > | >> | >> >> | > I'd experiment with one of the smaller changes you | describe, | >> | >> >> | > such | >> | >> >> as | >> | >> >> | adding a putStrLn, and comparing Core, before and after. | >> | >> >> | Switching | >> | >> >> off - | >> | >> >> | O will make a huge difference, so hard to compare. Turning | off | >> | >> >> | the | >> | >> >> state | >> | >> >> | hack will have a more global effect. But the other changes | >> | >> >> | sound | >> | >> >> more | >> | >> >> | pin-point and hence the differences will be smaller. | >> | >> >> | > | >> | >> >> | > Simon | >> | >> >> | > | >> | >> >> | > | -----Original Message----- | >> | >> >> | > | From: ghc-devs [mailto:ghc-devs-bounces@haskell.org] | On | >> | >> >> | > | Behalf | >> | >> >> Of | >> | >> >> | Neil | >> | >> >> | > | Mitchell | >> | >> >> | > | Sent: 18 March 2015 15:33 | >> | >> >> | > | To: ghc-devs(a)haskell.org | >> | >> >> | > | Subject: Shake fails test with GHC 7.10 RC3 | >> | >> >> | > | | >> | >> >> | > | Hi, | >> | >> >> | > | | >> | >> >> | > | Testing GHC 7.10 RC3 I've found a bug where Shake | seems to | >> | >> >> | > | catch | >> | >> >> the | >> | >> >> | > | wrong exception in the wrong place. It's only hit by | one of | >> | >> >> | > | my | >> | >> >> | tests, | >> | >> >> | > | and I've managed to isolate it to a fragment of code | with | >> | >> >> | > | no unsafePerformIO, that throws exceptions using error | (so | >> | >> >> | > | not in | >> | >> >> IO), | >> | >> >> | and | >> | >> >> | > | operates in IO. Turning off the stack hack makes the | bug go | >> | >> >> away, | >> | >> >> | but | >> | >> >> | > | then so does -O0, marking one of the functions it | calls | >> | >> >> NOINLINE, or | >> | >> >> | > | moving an INLINE function it calls to a different | module, | >> | >> >> | > | or | >> | >> >> adding | >> | >> >> | a | >> | >> >> | > | putStrLn under a catch block - it's very sensitive to | the | >> | >> >> | > | exact conditions. This test and this exact code worked | fine | >> | >> >> | > | with GHC | >> | >> >> 7.10 | >> | >> >> | > | RC2. | >> | >> >> | > | | >> | >> >> | > | I was wondering if there have been any state hack | related | >> | >> >> changes or | >> | >> >> | > | other potentially dangerous optimisation changes since | RC2? | >> | >> >> | > | I'll continue to try reducing the bug, but it's | somewhat | >> | >> >> | > | difficult as | >> | >> >> the | >> | >> >> | > | larger system is quite big, and the code is very | sensitive. | >> | >> >> | > | | >> | >> >> | > | Thanks, Neil | >> | >> >> | > | _______________________________________________ | >> | >> >> | > | ghc-devs mailing list | >> | >> >> | > | ghc-devs(a)haskell.org | >> | >> >> | > | http://mail.haskell.org/cgi-bin/mailman/listinfo/ghc- | devs | >> | >> _______________________________________________ | >> | >> ghc-devs mailing list | >> | >> ghc-devs(a)haskell.org | >> | >> http://mail.haskell.org/cgi-bin/mailman/listinfo/ghc-devs | >> | > | >> | > | >> _______________________________________________ | >> ghc-devs mailing list | >> ghc-devs(a)haskell.org | >> http://mail.haskell.org/cgi-bin/mailman/listinfo/ghc-devs | > | > -- | > "Elegance is not optional" -- Richard O'Keefe | > | | | | -- | Regards, | | Austin Seipp, Haskell Consultant | Well-Typed LLP, http://www.well-typed.com/

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RE: [GHC] #10158: Panic compiling singletons: StgCmmEnv: variable not found
by Simon Peyton Jones 20 Mar '15

20 Mar '15

Replying by email since Trac is down. I nailed this one. This diff fixes it. It was a missing 'runFlatten'. However I propose not to commit a fix, because Richard's D653 refactors all that code and, I'm 99% certain, fixes the bug in a better way. I would like D653 to land though. Richard are you doing that, or are you waiting for Austin to? Simon Modified compiler/typecheck/TcInteract.hs diff --git a/compiler/typecheck/TcInteract.hs b/compiler/typecheck/TcInteract.hs index e83709c..4d4b31c 100644 --- a/compiler/typecheck/TcInteract.hs +++ b/compiler/typecheck/TcInteract.hs @@ -1420,6 +1420,7 @@ shortCutReduction old_ev fsk ax_co fam_tc tc_args | otherwise = ASSERT( not (isDerived old_ev) ) -- Caller ensures this ASSERT( ctEvEqRel old_ev == NomEq ) + runFlatten $ do { (xis, cos) <- flattenManyNom old_ev tc_args -- ax_co :: F args ~ G tc_args -- cos :: xis ~ tc_args | -----Original Message----- | From: ghc-tickets [mailto:ghc-tickets-bounces@haskell.org] On Behalf Of | GHC | Sent: 14 March 2015 03:07 | Cc: ghc-tickets(a)haskell.org | Subject: Re: [GHC] #10158: Panic compiling singletons: StgCmmEnv: | variable not found | | #10158: Panic compiling singletons: StgCmmEnv: variable not found | -------------------------------------+----------------------------------- | -- | Reporter: trommler | Owner: | Type: bug | Status: new | Priority: highest | Milestone: | Component: Compiler | Version: 7.11 | (CodeGen) | Keywords: | Resolution: | Architecture: | Operating System: Unknown/Multiple | Unknown/Multiple | Type of failure: None/Unknown | Test Case: | Blocked By: | Blocking: | Related Tickets: | Differential Revisions: | -------------------------------------+----------------------------------- | -- | Changes (by goldfire): | | * priority: normal => highest | | | Comment: | | Yikes! I hope I'm not overstating the importance of my library to GHC, | but | this sounds serious. | | Is this reproducible on the 7.10 branch? If so, please set the milestone | to 7.10.1. | | -- | Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/10158#comment:1> | GHC <http://www.haskell.org/ghc/> | The Glasgow Haskell Compiler | _______________________________________________ | ghc-tickets mailing list | ghc-tickets(a)haskell.org | http://mail.haskell.org/cgi-bin/mailman/listinfo/ghc-tickets

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Shake fails test with GHC 7.10 RC3
by Neil Mitchell 20 Mar '15

20 Mar '15

Hi, Testing GHC 7.10 RC3 I've found a bug where Shake seems to catch the wrong exception in the wrong place. It's only hit by one of my tests, and I've managed to isolate it to a fragment of code with no unsafePerformIO, that throws exceptions using error (so not in IO), and operates in IO. Turning off the stack hack makes the bug go away, but then so does -O0, marking one of the functions it calls NOINLINE, or moving an INLINE function it calls to a different module, or adding a putStrLn under a catch block - it's very sensitive to the exact conditions. This test and this exact code worked fine with GHC 7.10 RC2. I was wondering if there have been any state hack related changes or other potentially dangerous optimisation changes since RC2? I'll continue to try reducing the bug, but it's somewhat difficult as the larger system is quite big, and the code is very sensitive. Thanks, Neil

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ANNOUNCE: GHC 7.10.1 Release Candidate 3
by Austin Seipp 19 Mar '15

19 Mar '15

We are pleased to announce the third release candidate for GHC 7.10.1: https://downloads.haskell.org/~ghc/7.10.1-rc3 https://downloads.haskell.org/~ghc/7.10.1-rc3/docs/html/ This includes the source tarball and bindists for Windows and Debian Linux. FreeBSD, CentOS and Mac OS X binary distributions will follow soon. These binaries and tarballs have an accompanying SHA256SUMS file signed by my GPG key id (0x3B58D86F). We plan to make the 7.10.1 final release at the end of this week - so please test as much as possible; bugs are much cheaper if we find them before the release! The list of issues we plan on fixing can always be found in an up-to-date form here: https://ghc.haskell.org/trac/ghc/wiki/Status/GHC-7.10.1 -- Regards, Austin Seipp, Haskell Consultant Well-Typed LLP, http://www.well-typed.com/

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