Re: [GHC] #7361: Segmentation fault on 5f37e0c71ff4af8539c5aebc739b006b4f0c6ebf
#7361: Segmentation fault on 5f37e0c71ff4af8539c5aebc739b006b4f0c6ebf -+-- Reporter: bgamari | Owner: simonmar Type: bug | Status: infoneeded Priority: highest | Milestone: 7.8.1 Component: Compiler | Version: 7.7 Keywords:| Os: Unknown/Multiple Architecture: Unknown/Multiple | Failure: Runtime crash Difficulty: Unknown |Testcase: Blockedby:|Blocking: Related:| -+-- Comment(by simonmar): The `ByteArray#` code seems to come from `vector`, because the `ByteArray#` is inside an `MVector` constructor (from `Data.Vector.Primitive.Mutable`). -- Ticket URL: http://hackage.haskell.org/trac/ghc/ticket/7361#comment:25 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler ___ Glasgow-haskell-bugs mailing list Glasgow-haskell-bugs@haskell.org http://www.haskell.org/mailman/listinfo/glasgow-haskell-bugs
Re: [GHC] #7361: Segmentation fault on 5f37e0c71ff4af8539c5aebc739b006b4f0c6ebf
#7361: Segmentation fault on 5f37e0c71ff4af8539c5aebc739b006b4f0c6ebf -+-- Reporter: bgamari | Owner: simonmar Type: bug | Status: infoneeded Priority: highest | Milestone: 7.8.1 Component: Compiler | Version: 7.7 Keywords:| Os: Unknown/Multiple Architecture: Unknown/Multiple | Failure: Runtime crash Difficulty: Unknown |Testcase: Blockedby:|Blocking: Related:| -+-- Comment(by bgamari): Yes, this lends further support to the hypothesis that the it is mwc- random, not random-source, which is at fault. mwc-random uses an MVector to hold the RNG state. Sadly, I've still been unsuccessful at producing a testcase using only mwc-random. -- Ticket URL: http://hackage.haskell.org/trac/ghc/ticket/7361#comment:26 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler ___ Glasgow-haskell-bugs mailing list Glasgow-haskell-bugs@haskell.org http://www.haskell.org/mailman/listinfo/glasgow-haskell-bugs
Re: [GHC] #7361: Segmentation fault on 5f37e0c71ff4af8539c5aebc739b006b4f0c6ebf
#7361: Segmentation fault on 5f37e0c71ff4af8539c5aebc739b006b4f0c6ebf -+-- Reporter: bgamari | Owner: simonmar Type: bug | Status: infoneeded Priority: highest | Milestone: 7.8.1 Component: Compiler | Version: 7.7 Keywords:| Os: Unknown/Multiple Architecture: Unknown/Multiple | Failure: Runtime crash Difficulty: Unknown |Testcase: Blockedby:|Blocking: Related:| -+-- Comment(by bgamari): Indeed, using bound-checked reads and writes in place of the unsafe varieties currently used in System.Random.MWC reveals that uniform1 is the culprit. -- Ticket URL: http://hackage.haskell.org/trac/ghc/ticket/7361#comment:27 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler ___ Glasgow-haskell-bugs mailing list Glasgow-haskell-bugs@haskell.org http://www.haskell.org/mailman/listinfo/glasgow-haskell-bugs
Re: [GHC] #7361: Segmentation fault on 5f37e0c71ff4af8539c5aebc739b006b4f0c6ebf
#7361: Segmentation fault on 5f37e0c71ff4af8539c5aebc739b006b4f0c6ebf -+-- Reporter: bgamari | Owner: simonmar Type: bug | Status: infoneeded Priority: highest | Milestone: 7.8.1 Component: Compiler | Version: 7.7 Keywords:| Os: Unknown/Multiple Architecture: Unknown/Multiple | Failure: Runtime crash Difficulty: Unknown |Testcase: Blockedby:|Blocking: Related:| -+-- Comment(by bgamari): In particular, it appears to be the `M.read q i` in `uniformWord32` -- Ticket URL: http://hackage.haskell.org/trac/ghc/ticket/7361#comment:28 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler ___ Glasgow-haskell-bugs mailing list Glasgow-haskell-bugs@haskell.org http://www.haskell.org/mailman/listinfo/glasgow-haskell-bugs
Re: [GHC] #7361: Segmentation fault on 5f37e0c71ff4af8539c5aebc739b006b4f0c6ebf
#7361: Segmentation fault on 5f37e0c71ff4af8539c5aebc739b006b4f0c6ebf
-+--
Reporter: bgamari | Owner: simonmar
Type: bug | Status: infoneeded
Priority: highest | Milestone: 7.8.1
Component: Compiler | Version: 7.7
Keywords:| Os: Unknown/Multiple
Architecture: Unknown/Multiple | Failure: Runtime crash
Difficulty: Unknown |Testcase:
Blockedby:|Blocking:
Related:|
-+--
Comment(by bgamari):
Well, it seems that `nextIndex` isn't wrapping correctly when used in
`uniformWord32`. Currently it is implemented as,
{{{
nextIndex :: Integral a = a - Int
nextIndex i = fromIntegral j
where j = fromIntegral (i+1) :: Word8
}}}
If I trace the index values over iterations of `uniformWord32`, I find
that they grow beyond 256, resulting in the crash.
If I implement `nextIndex` with a simple `mod`, on the other hand, things
work fine,
{{{
nextIndex :: Integral a = a - Int
nextIndex i = fromIntegral $ (i + 1) `mod` 256
}}}
Simon, is it possible that the optimizer could be now optimizing out the
cast?
--
Ticket URL: http://hackage.haskell.org/trac/ghc/ticket/7361#comment:29
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Re: [GHC] #7361: Segmentation fault on 5f37e0c71ff4af8539c5aebc739b006b4f0c6ebf
#7361: Segmentation fault on 5f37e0c71ff4af8539c5aebc739b006b4f0c6ebf -+-- Reporter: bgamari | Owner: simonmar Type: bug | Status: infoneeded Priority: highest | Milestone: 7.8.1 Component: Compiler | Version: 7.7 Keywords:| Os: Unknown/Multiple Architecture: Unknown/Multiple | Failure: Runtime crash Difficulty: Unknown |Testcase: Blockedby:|Blocking: Related:| -+-- Comment(by simonmar): Great analysis, thanks. We do indeed seem to have lost the narrowing in `nextIndex`, and it happens in Core, so nothing to do with the code generator. I'll dig a bit deeper and see if I can find out where we went wrong. -- Ticket URL: http://hackage.haskell.org/trac/ghc/ticket/7361#comment:30 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler ___ Glasgow-haskell-bugs mailing list Glasgow-haskell-bugs@haskell.org http://www.haskell.org/mailman/listinfo/glasgow-haskell-bugs
Re: [GHC] #7361: Segmentation fault on 5f37e0c71ff4af8539c5aebc739b006b4f0c6ebf
#7361: Segmentation fault on 5f37e0c71ff4af8539c5aebc739b006b4f0c6ebf -+-- Reporter: bgamari | Owner: simonmar Type: bug | Status: infoneeded Priority: highest | Milestone: 7.8.1 Component: Compiler | Version: 7.7 Keywords:| Os: Unknown/Multiple Architecture: Unknown/Multiple | Failure: Runtime crash Difficulty: Unknown |Testcase: Blockedby:|Blocking: Related:| -+-- Comment(by simonmar): Got it - bogus rules for `narrow8Int#` and friends in `PrelRules`. Fix coming. -- Ticket URL: http://hackage.haskell.org/trac/ghc/ticket/7361#comment:31 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler ___ Glasgow-haskell-bugs mailing list Glasgow-haskell-bugs@haskell.org http://www.haskell.org/mailman/listinfo/glasgow-haskell-bugs
Re: [GHC] #7361: Segmentation fault on 5f37e0c71ff4af8539c5aebc739b006b4f0c6ebf
#7361: Segmentation fault on 5f37e0c71ff4af8539c5aebc739b006b4f0c6ebf
-+--
Reporter: bgamari | Owner: simonmar
Type: bug | Status: infoneeded
Priority: highest | Milestone: 7.8.1
Component: Compiler | Version: 7.7
Keywords:| Os: Unknown/Multiple
Architecture: Unknown/Multiple | Failure: Runtime crash
Difficulty: Unknown |Testcase:
Blockedby:|Blocking:
Related:|
-+--
Comment(by marlowsd@…):
commit 3af022f3ae6ff3adceb2318cf50549d954e8bbe7
{{{
Author: Simon Marlow marlo...@gmail.com
Date: Wed Jan 9 16:52:16 2013 +
Fix some incorrect narrowing rules (#7361)
e.g. narrow8Int# subsumes narrow16Int#, not the other way around.
compiler/prelude/PrelRules.lhs | 24
1 files changed, 12 insertions(+), 12 deletions(-)
}}}
--
Ticket URL: http://hackage.haskell.org/trac/ghc/ticket/7361#comment:32
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Re: [GHC] #7361: Segmentation fault on 5f37e0c71ff4af8539c5aebc739b006b4f0c6ebf
#7361: Segmentation fault on 5f37e0c71ff4af8539c5aebc739b006b4f0c6ebf ---+ Reporter: bgamari | Owner: simonmar Type: bug | Status: closed Priority: highest | Milestone: 7.8.1 Component: Compiler |Version: 7.7 Resolution: fixed | Keywords: Os: Unknown/Multiple | Architecture: Unknown/Multiple Failure: Runtime crash | Difficulty: Unknown Testcase:| Blockedby: Blocking:|Related: ---+ Changes (by simonmar): * status: infoneeded = closed * resolution: = fixed -- Ticket URL: http://hackage.haskell.org/trac/ghc/ticket/7361#comment:33 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler ___ Glasgow-haskell-bugs mailing list Glasgow-haskell-bugs@haskell.org http://www.haskell.org/mailman/listinfo/glasgow-haskell-bugs
Re: [GHC] #7361: Segmentation fault on 5f37e0c71ff4af8539c5aebc739b006b4f0c6ebf
#7361: Segmentation fault on 5f37e0c71ff4af8539c5aebc739b006b4f0c6ebf ---+ Reporter: bgamari | Owner: simonmar Type: bug | Status: closed Priority: highest | Milestone: 7.8.1 Component: Compiler |Version: 7.7 Resolution: fixed | Keywords: Os: Unknown/Multiple | Architecture: Unknown/Multiple Failure: Runtime crash | Difficulty: Unknown Testcase:| Blockedby: Blocking:|Related: ---+ Comment(by bgamari): Thanks! -- Ticket URL: http://hackage.haskell.org/trac/ghc/ticket/7361#comment:34 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler ___ Glasgow-haskell-bugs mailing list Glasgow-haskell-bugs@haskell.org http://www.haskell.org/mailman/listinfo/glasgow-haskell-bugs
Re: [GHC] #7361: Segmentation fault on 5f37e0c71ff4af8539c5aebc739b006b4f0c6ebf
#7361: Segmentation fault on 5f37e0c71ff4af8539c5aebc739b006b4f0c6ebf
-+--
Reporter: bgamari | Owner: simonmar
Type: bug | Status: infoneeded
Priority: highest | Milestone: 7.8.1
Component: Compiler | Version: 7.7
Keywords:| Os: Unknown/Multiple
Architecture: Unknown/Multiple | Failure: Runtime crash
Difficulty: Unknown |Testcase:
Blockedby:|Blocking:
Related:|
-+--
Changes (by simonmar):
* status: new = infoneeded
Comment:
I reproduced it again today, but the bug still eludes me. The code is
reading and writing beyond the end of a `ByteArray#`, and I can't tell
whether this is a codegen bug or a library bug that has gone unnoticed so
far.
The crash still happens with `-fno-cmm-sink` and with `-fllvm`, which
eliminates the two things that I would be most suspicious of (the Cmm
sinking pass and the native code generator).
The code that writes over the end of the array is
`Data.Random.Source.MWC.$wa`. This function is large and complicated and
the code is TH-generated, so I'm a bit lost here. I tried to follow the
code and couldn't see any codegen bugs though.
The erroneous access happens on the 3rd call, where the arguments are a
normal-looking `MVector`:
{{{
(gdb) p4 0x2c40bde9
0x2c40be00: 0x102
0x2c40bdf8: 0x0
0x2c40bdf0: 0x2c405628
0x2c40bde8: 0x4cc3d0
vectorzm0zi10zi0zi1_DataziVectorziPrimitiveziMutable_MVector_con_info
}}}
and an `Int#` value 1.
Maybe someone familiar with `random-source` could add some debugging tests
and try to narrow down the failure?
--
Ticket URL: http://hackage.haskell.org/trac/ghc/ticket/7361#comment:21
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Re: [GHC] #7361: Segmentation fault on 5f37e0c71ff4af8539c5aebc739b006b4f0c6ebf
#7361: Segmentation fault on 5f37e0c71ff4af8539c5aebc739b006b4f0c6ebf -+-- Reporter: bgamari | Owner: simonmar Type: bug | Status: infoneeded Priority: highest | Milestone: 7.8.1 Component: Compiler | Version: 7.7 Keywords:| Os: Unknown/Multiple Architecture: Unknown/Multiple | Failure: Runtime crash Difficulty: Unknown |Testcase: Blockedby:|Blocking: Related:| -+-- Comment(by bgamari): I've let the maintainer (James Cook) know. He's been quite responsive in the past so I suspect I'll hear back shortly. Thanks again for your time! -- Ticket URL: http://hackage.haskell.org/trac/ghc/ticket/7361#comment:22 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler ___ Glasgow-haskell-bugs mailing list Glasgow-haskell-bugs@haskell.org http://www.haskell.org/mailman/listinfo/glasgow-haskell-bugs
Re: [GHC] #7361: Segmentation fault on 5f37e0c71ff4af8539c5aebc739b006b4f0c6ebf
#7361: Segmentation fault on 5f37e0c71ff4af8539c5aebc739b006b4f0c6ebf -+-- Reporter: bgamari | Owner: simonmar Type: bug | Status: infoneeded Priority: highest | Milestone: 7.8.1 Component: Compiler | Version: 7.7 Keywords:| Os: Unknown/Multiple Architecture: Unknown/Multiple | Failure: Runtime crash Difficulty: Unknown |Testcase: Blockedby:|Blocking: Related:| -+-- Comment(by bgamari): I'm not sure why this didn't occur to me earlier, but it seems much more likely that mwc-random is the culprit here (I'm fairly certain that mwc- random uses ByteArray#s whereas random-source does not). So far my attempts at producing a crashing bit of code (or even one producing valgrind errors) using only mwc-random have turned up nothing, but I'll keep trying. I've let bos know. Perhaps we'll hear from him soon. -- Ticket URL: http://hackage.haskell.org/trac/ghc/ticket/7361#comment:23 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler ___ Glasgow-haskell-bugs mailing list Glasgow-haskell-bugs@haskell.org http://www.haskell.org/mailman/listinfo/glasgow-haskell-bugs
Re: [GHC] #7361: Segmentation fault on 5f37e0c71ff4af8539c5aebc739b006b4f0c6ebf
#7361: Segmentation fault on 5f37e0c71ff4af8539c5aebc739b006b4f0c6ebf -+-- Reporter: bgamari | Owner: simonmar Type: bug | Status: infoneeded Priority: highest | Milestone: 7.8.1 Component: Compiler | Version: 7.7 Keywords:| Os: Unknown/Multiple Architecture: Unknown/Multiple | Failure: Runtime crash Difficulty: Unknown |Testcase: Blockedby:|Blocking: Related:| -+-- Changes (by bos): * cc: bos@… (added) -- Ticket URL: http://hackage.haskell.org/trac/ghc/ticket/7361#comment:24 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler ___ Glasgow-haskell-bugs mailing list Glasgow-haskell-bugs@haskell.org http://www.haskell.org/mailman/listinfo/glasgow-haskell-bugs
Re: [GHC] #7361: Segmentation fault on 5f37e0c71ff4af8539c5aebc739b006b4f0c6ebf
#7361: Segmentation fault on 5f37e0c71ff4af8539c5aebc739b006b4f0c6ebf -+-- Reporter: bgamari | Owner: simonmar Type: bug | Status: new Priority: highest | Milestone: 7.8.1 Component: Compiler | Version: 7.7 Keywords:| Os: Unknown/Multiple Architecture: Unknown/Multiple | Failure: Runtime crash Difficulty: Unknown |Testcase: Blockedby:|Blocking: Related:| -+-- Comment(by bgamari): It seems this can still be reproduced with `db9c062a4a7c39563a3a9a83718cc0ce6d4babae`. -- Ticket URL: http://hackage.haskell.org/trac/ghc/ticket/7361#comment:20 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler ___ Glasgow-haskell-bugs mailing list Glasgow-haskell-bugs@haskell.org http://www.haskell.org/mailman/listinfo/glasgow-haskell-bugs
Re: [GHC] #7361: Segmentation fault on 5f37e0c71ff4af8539c5aebc739b006b4f0c6ebf
#7361: Segmentation fault on 5f37e0c71ff4af8539c5aebc739b006b4f0c6ebf -+-- Reporter: bgamari | Owner: simonmar Type: bug | Status: new Priority: highest | Milestone: 7.8.1 Component: Compiler | Version: 7.7 Keywords:| Os: Unknown/Multiple Architecture: Unknown/Multiple | Failure: Runtime crash Difficulty: Unknown |Testcase: Blockedby:|Blocking: Related:| -+-- Comment(by bgamari): Simon, can I do anything else to help here? -- Ticket URL: http://hackage.haskell.org/trac/ghc/ticket/7361#comment:19 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler ___ Glasgow-haskell-bugs mailing list Glasgow-haskell-bugs@haskell.org http://www.haskell.org/mailman/listinfo/glasgow-haskell-bugs
Re: [GHC] #7361: Segmentation fault on 5f37e0c71ff4af8539c5aebc739b006b4f0c6ebf
#7361: Segmentation fault on 5f37e0c71ff4af8539c5aebc739b006b4f0c6ebf
-+--
Reporter: bgamari | Owner: simonmar
Type: bug | Status: infoneeded
Priority: highest | Milestone: 7.8.1
Component: Compiler | Version: 7.7
Keywords:| Os: Unknown/Multiple
Architecture: Unknown/Multiple | Failure: Runtime crash
Difficulty: Unknown |Testcase:
Blockedby:|Blocking:
Related:|
-+--
Comment(by bgamari):
Sorry for the latency. I've tried to pull again and now sit on
4f7027d6947af9c5cdecc0c18097268594c4592b. Sadly the crash in Test2.hs is
still reproducible for me. I should have pointed out the mersenne-random-
pure64 incompatibility earlier. The only change I have made here is
s/GHC.IOBase/GHC.IO/ as you point out.
I am also on x86_64/Linux. The exact dependencies (extracted from ghc -v)
are,
{{{
random-fu-0.2.3.1
rvar-0.2.0.1
random-source-0.3.0.2
stateref-0.3
random-shuffle-0.0.4
mwc-random-0.12.0.1
monad-loops-0.3.3.0
stm-2.4.2
mersenne-random-pure64-0.2.0.3
old-time-1.1.0.1
gamma-0.9.0.2
vector-0.10.0.1
primitive-0.5.0.1
flexible-defaults-0.0.1.0
th-extras-0.0.0.1
syb-0.3.7
template-haskell-2.9.0.0
pretty-1.1.1.0
erf-2.0.0.0
converge-0.1.0.1
continued-fractions-0.9.1.1
containers-0.5.0.0
MonadRandom-0.1.8
random-1.0.1.1
time-1.4.0.2
old-locale-1.0.0.5
deepseq-1.3.0.2
array-0.4.0.2
MonadPrompt-1.0.0.3
mtl-2.1.2
transformers-0.3.0.0
base-4.7.0.0
integer-gmp-0.5.1.0
ghc-prim-0.3.1.0
}}}
The uncommented regions of build.mk are,
{{{
BuildFlavour = perf
ifeq $(BuildFlavour) perf
# perf matches the default settings, repeated here for comparison:
SRC_HC_OPTS = -O -H64m
GhcStage1HcOpts = -O -fasm
GhcStage2HcOpts = -O2 -fasm
GhcHcOpts = -Rghc-timing
GhcLibHcOpts= -O2
GhcLibWays += p
ifeq $(PlatformSupportsSharedLibs) YES
GhcLibWays += dyn
endif
endif
# NoFib settings
NoFibWays =
STRIP_CMD = :
}}}
Likewise for ~/.cabal/config,
{{{
remote-repo:
hackage.haskell.org:http://hackage.haskell.org/packages/archive
remote-repo-cache: /home/ben/.cabal/packages
world-file: /home/ben/.cabal/world
library-profiling: True
}}}
Congratulations on your new job!
--
Ticket URL: http://hackage.haskell.org/trac/ghc/ticket/7361#comment:17
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Re: [GHC] #7361: Segmentation fault on 5f37e0c71ff4af8539c5aebc739b006b4f0c6ebf
#7361: Segmentation fault on 5f37e0c71ff4af8539c5aebc739b006b4f0c6ebf -+-- Reporter: bgamari | Owner: simonmar Type: bug | Status: new Priority: highest | Milestone: 7.8.1 Component: Compiler | Version: 7.7 Keywords:| Os: Unknown/Multiple Architecture: Unknown/Multiple | Failure: Runtime crash Difficulty: Unknown |Testcase: Blockedby:|Blocking: Related:| -+-- Changes (by bgamari): * status: infoneeded = new -- Ticket URL: http://hackage.haskell.org/trac/ghc/ticket/7361#comment:18 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler ___ Glasgow-haskell-bugs mailing list Glasgow-haskell-bugs@haskell.org http://www.haskell.org/mailman/listinfo/glasgow-haskell-bugs
Re: [GHC] #7361: Segmentation fault on 5f37e0c71ff4af8539c5aebc739b006b4f0c6ebf
#7361: Segmentation fault on 5f37e0c71ff4af8539c5aebc739b006b4f0c6ebf -+-- Reporter: bgamari | Owner: simonmar Type: bug | Status: infoneeded Priority: highest | Milestone: 7.8.1 Component: Compiler | Version: 7.7 Keywords:| Os: Unknown/Multiple Architecture: Unknown/Multiple | Failure: Runtime crash Difficulty: Unknown |Testcase: Blockedby:|Blocking: Related:| -+-- Changes (by simonmar): * status: new = infoneeded Comment: Tried again today, and it still doesn't reproduce for me on x86_64/Linux. I'll need all the information about your specific setup to reproduce it: `build.mk`, exact version of every dependent package (I had to modify `mersenne-random-pure64` to get it to build, removing the import of `GHC.IOBase`), and any relevant `.cabal/config` settings. -- Ticket URL: http://hackage.haskell.org/trac/ghc/ticket/7361#comment:16 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler ___ Glasgow-haskell-bugs mailing list Glasgow-haskell-bugs@haskell.org http://www.haskell.org/mailman/listinfo/glasgow-haskell-bugs
Re: [GHC] #7361: Segmentation fault on 5f37e0c71ff4af8539c5aebc739b006b4f0c6ebf
#7361: Segmentation fault on 5f37e0c71ff4af8539c5aebc739b006b4f0c6ebf
-+--
Reporter: bgamari | Owner: simonmar
Type: bug | Status: new
Priority: highest | Milestone: 7.8.1
Component: Compiler | Version: 7.7
Keywords:| Os: Unknown/Multiple
Architecture: Unknown/Multiple | Failure: Runtime crash
Difficulty: Unknown |Testcase:
Blockedby:|Blocking:
Related:|
-+--
Comment(by simonmar):
I did manage to get this built eventually (after much yak-shaving), but it
doesn't crash for me any more.
{{{
./7361
[Node 10,Node 57,Node 57,Node 80,Node 33,Node 47,Node 13,Node 58,Node
13,Node 44,Node 76,Node 13,Node 44,Node 47,Node 58,Node 80,Node 87,Node
15,Node 52,Node 90,Node 67,Node 29,Node 80,Node 87,Node 15,Node 52,Node
90,Node 67,Node 35,Node 41,Node 23,Node 26,Node 65,Node 89,Node 9,Node
58,Node 92,Node 13,Node 44,Node 47,Node 14,Node 51,Node 53,Node 86,Node
55,Node 98,Node 48,Node 10,Node 72,Node 12,Node 65,Node 49,Node 11,Node
9,Node 48,Node 1,Node 87,Node 71,Node 45,Node 7,Node 97,Node 84,Node
80,Node 87,Node 15,Node 52,Node 90,Node 67,Node 35,Node 41,Node 23,Node
26,Node 65,Node 89,Node 9,Node 77,Node 10,Node 36,Node 84,Node 10,Node
31,Node 46,Node 81,Node 49,Node 86,Node 1,Node 17,Node 94,Node 62,Node
3,Node 20,Node 99,Node 64,Node 8,Node 49,Node 10,Node 35,Node 84,Node
34,Node 34]
}}}
--
Ticket URL: http://hackage.haskell.org/trac/ghc/ticket/7361#comment:14
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Re: [GHC] #7361: Segmentation fault on 5f37e0c71ff4af8539c5aebc739b006b4f0c6ebf
#7361: Segmentation fault on 5f37e0c71ff4af8539c5aebc739b006b4f0c6ebf -+-- Reporter: bgamari | Owner: simonmar Type: bug | Status: new Priority: highest | Milestone: 7.8.1 Component: Compiler | Version: 7.7 Keywords:| Os: Unknown/Multiple Architecture: Unknown/Multiple | Failure: Runtime crash Difficulty: Unknown |Testcase: Blockedby:|Blocking: Related:| -+-- Comment(by bgamari): Oh dear. I do know that unfortunately the program is sensitive to the number of replications passed to replicate. With 30 iterations, the program crashes for me roughly half the time. With 28 it practically never crashes. Perhaps try raising this number? Moreover, the case Test2.hs that I'm about to attach is slightly more minimal and also crashes. This demonstrates that, as expected, the newtypes don't contribute to the crash, nor does the (=); it's strictly a matter of how many numbers are generated. -- Ticket URL: http://hackage.haskell.org/trac/ghc/ticket/7361#comment:15 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler ___ Glasgow-haskell-bugs mailing list Glasgow-haskell-bugs@haskell.org http://www.haskell.org/mailman/listinfo/glasgow-haskell-bugs
Re: [GHC] #7361: Segmentation fault on 5f37e0c71ff4af8539c5aebc739b006b4f0c6ebf
#7361: Segmentation fault on 5f37e0c71ff4af8539c5aebc739b006b4f0c6ebf -+-- Reporter: bgamari | Owner: simonmar Type: bug | Status: new Priority: highest | Milestone: 7.8.1 Component: Compiler | Version: 7.7 Keywords:| Os: Unknown/Multiple Architecture: Unknown/Multiple | Failure: Runtime crash Difficulty: Unknown |Testcase: Blockedby:|Blocking: Related:| -+-- Comment(by simonmar): Does this still happen for you? I've fixed the other outstanding bugs that I know about in the new code generator, so now would be a good time to test again. -- Ticket URL: http://hackage.haskell.org/trac/ghc/ticket/7361#comment:10 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler ___ Glasgow-haskell-bugs mailing list Glasgow-haskell-bugs@haskell.org http://www.haskell.org/mailman/listinfo/glasgow-haskell-bugs
Re: [GHC] #7361: Segmentation fault on 5f37e0c71ff4af8539c5aebc739b006b4f0c6ebf
#7361: Segmentation fault on 5f37e0c71ff4af8539c5aebc739b006b4f0c6ebf -+-- Reporter: bgamari | Owner: simonmar Type: bug | Status: new Priority: highest | Milestone: 7.8.1 Component: Compiler | Version: 7.7 Keywords:| Os: Unknown/Multiple Architecture: Unknown/Multiple | Failure: Runtime crash Difficulty: Unknown |Testcase: Blockedby:|Blocking: Related:| -+-- Comment(by bgamari): I've been trying to get a ghc built but unfortunately the DYNAMIC_BY_DEFAULT change has really broken quite a bit it seems, particularly when profiling is enabled. I've documented a few of the issues [http://www.haskell.org/pipermail/cvs-ghc/2012-November/078502.html here]. That being said, I think I have something building now. I'll let you know when I have some results. -- Ticket URL: http://hackage.haskell.org/trac/ghc/ticket/7361#comment:11 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler ___ Glasgow-haskell-bugs mailing list Glasgow-haskell-bugs@haskell.org http://www.haskell.org/mailman/listinfo/glasgow-haskell-bugs
Re: [GHC] #7361: Segmentation fault on 5f37e0c71ff4af8539c5aebc739b006b4f0c6ebf
#7361: Segmentation fault on 5f37e0c71ff4af8539c5aebc739b006b4f0c6ebf -+-- Reporter: bgamari | Owner: simonmar Type: bug | Status: new Priority: highest | Milestone: 7.8.1 Component: Compiler | Version: 7.7 Keywords:| Os: Unknown/Multiple Architecture: Unknown/Multiple | Failure: Runtime crash Difficulty: Unknown |Testcase: Blockedby:|Blocking: Related:| -+-- Comment(by bgamari): Unfortunately the segmentation fault is still reproducible on 6486213bc4ad307273956bc6164eeeb3f6f31d1c. -- Ticket URL: http://hackage.haskell.org/trac/ghc/ticket/7361#comment:12 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler ___ Glasgow-haskell-bugs mailing list Glasgow-haskell-bugs@haskell.org http://www.haskell.org/mailman/listinfo/glasgow-haskell-bugs
Re: [GHC] #7361: Segmentation fault on 5f37e0c71ff4af8539c5aebc739b006b4f0c6ebf
#7361: Segmentation fault on 5f37e0c71ff4af8539c5aebc739b006b4f0c6ebf -+-- Reporter: bgamari | Owner: simonmar Type: bug | Status: new Priority: highest | Milestone: 7.8.1 Component: Compiler | Version: 7.7 Keywords:| Os: Unknown/Multiple Architecture: Unknown/Multiple | Failure: Runtime crash Difficulty: Unknown |Testcase: Blockedby:|Blocking: Related:| -+-- Comment(by bgamari): I've attached Test.hs which is a slightly more compact testcase. While it gets nowhere near isolating the root cause of the crash, at least you don't need to clone all of bayes-stack to test. -- Ticket URL: http://hackage.haskell.org/trac/ghc/ticket/7361#comment:13 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler ___ Glasgow-haskell-bugs mailing list Glasgow-haskell-bugs@haskell.org http://www.haskell.org/mailman/listinfo/glasgow-haskell-bugs
Re: [GHC] #7361: Segmentation fault on 5f37e0c71ff4af8539c5aebc739b006b4f0c6ebf
#7361: Segmentation fault on 5f37e0c71ff4af8539c5aebc739b006b4f0c6ebf -+-- Reporter: bgamari | Owner: simonmar Type: bug | Status: new Priority: highest | Milestone: 7.8.1 Component: Compiler | Version: 7.7 Keywords:| Os: Unknown/Multiple Architecture: Unknown/Multiple | Failure: Runtime crash Difficulty: Unknown |Testcase: Blockedby:|Blocking: Related:| -+-- Comment(by simonmar): I reproduced this today, but didn't get very far with diagnosing it because the code that fails is very complicated. Something is writing beyond the end of an `ARR_WORDS`, and the code blob that does it is in `random-source:Data.Random.Source.MWC.$wa`, but that function is huge and I have no idea what it is supposed to do. The error could well be somewhere else. We could add some bounds checks to the array primitives (maybe with `-debug`), though I think it probably wouldn't help me in this case. I have some other bugs I'm chasing so hopefully this one will get fixed as a side-effect of fixing something else. Failing that, we will need a smaller test case. -- Ticket URL: http://hackage.haskell.org/trac/ghc/ticket/7361#comment:7 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler ___ Glasgow-haskell-bugs mailing list Glasgow-haskell-bugs@haskell.org http://www.haskell.org/mailman/listinfo/glasgow-haskell-bugs
Re: [GHC] #7361: Segmentation fault on 5f37e0c71ff4af8539c5aebc739b006b4f0c6ebf
#7361: Segmentation fault on 5f37e0c71ff4af8539c5aebc739b006b4f0c6ebf -+-- Reporter: bgamari | Owner: simonmar Type: bug | Status: new Priority: highest | Milestone: 7.8.1 Component: Compiler | Version: 7.7 Keywords:| Os: Unknown/Multiple Architecture: Unknown/Multiple | Failure: Runtime crash Difficulty: Unknown |Testcase: Blockedby:|Blocking: Related:| -+-- Comment(by bgamari): Alright, thanks for trying! I can try narrowing down the test case soon. -- Ticket URL: http://hackage.haskell.org/trac/ghc/ticket/7361#comment:8 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler ___ Glasgow-haskell-bugs mailing list Glasgow-haskell-bugs@haskell.org http://www.haskell.org/mailman/listinfo/glasgow-haskell-bugs
Re: [GHC] #7361: Segmentation fault on 5f37e0c71ff4af8539c5aebc739b006b4f0c6ebf
#7361: Segmentation fault on 5f37e0c71ff4af8539c5aebc739b006b4f0c6ebf -+-- Reporter: bgamari | Owner: simonmar Type: bug | Status: new Priority: highest | Milestone: 7.8.1 Component: Compiler | Version: 7.7 Keywords:| Os: Unknown/Multiple Architecture: Unknown/Multiple | Failure: Runtime crash Difficulty: Unknown |Testcase: Blockedby:|Blocking: Related:| -+-- Comment(by bgamari): Just for the record, my initial thought for a reproduction case (simply generating random variates with mwc-random through random-source) does not reproduce the crash. Looks like this could be a tricky crash to reproduce. Simon, I might wait a few days until some of the better understood crashes (if there is such a thing) are sorted out and reevaluate then. -- Ticket URL: http://hackage.haskell.org/trac/ghc/ticket/7361#comment:9 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler ___ Glasgow-haskell-bugs mailing list Glasgow-haskell-bugs@haskell.org http://www.haskell.org/mailman/listinfo/glasgow-haskell-bugs
Re: [GHC] #7361: Segmentation fault on 5f37e0c71ff4af8539c5aebc739b006b4f0c6ebf
#7361: Segmentation fault on 5f37e0c71ff4af8539c5aebc739b006b4f0c6ebf -+-- Reporter: bgamari | Owner: simonmar Type: bug | Status: new Priority: highest | Milestone: 7.8.1 Component: Compiler | Version: 7.7 Keywords:| Os: Unknown/Multiple Architecture: Unknown/Multiple | Failure: Runtime crash Difficulty: Unknown |Testcase: Blockedby:|Blocking: Related:| -+-- Changes (by simonmar): * owner: = simonmar Comment: This looks similar to a crash I'm currently investigating in `tests/concurrent/prog001/concprog001` (threaded2). I found a couple of bugs today, but there seems to be at least one remaining. Does your program need `-threaded` and/or +RTS -N to fail? -- Ticket URL: http://hackage.haskell.org/trac/ghc/ticket/7361#comment:5 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler ___ Glasgow-haskell-bugs mailing list Glasgow-haskell-bugs@haskell.org http://www.haskell.org/mailman/listinfo/glasgow-haskell-bugs
Re: [GHC] #7361: Segmentation fault on 5f37e0c71ff4af8539c5aebc739b006b4f0c6ebf
#7361: Segmentation fault on 5f37e0c71ff4af8539c5aebc739b006b4f0c6ebf -+-- Reporter: bgamari | Owner: simonmar Type: bug | Status: new Priority: highest | Milestone: 7.8.1 Component: Compiler | Version: 7.7 Keywords:| Os: Unknown/Multiple Architecture: Unknown/Multiple | Failure: Runtime crash Difficulty: Unknown |Testcase: Blockedby:|Blocking: Related:| -+-- Comment(by bgamari): No, the bug seems to be perfectly reproducible without -threaded. -- Ticket URL: http://hackage.haskell.org/trac/ghc/ticket/7361#comment:6 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler ___ Glasgow-haskell-bugs mailing list Glasgow-haskell-bugs@haskell.org http://www.haskell.org/mailman/listinfo/glasgow-haskell-bugs
Re: [GHC] #7361: Segmentation fault on 5f37e0c71ff4af8539c5aebc739b006b4f0c6ebf
#7361: Segmentation fault on 5f37e0c71ff4af8539c5aebc739b006b4f0c6ebf -+-- Reporter: bgamari | Owner: Type: bug | Status: new Priority: highest | Milestone: 7.8.1 Component: Compiler | Version: 7.7 Keywords:| Os: Unknown/Multiple Architecture: Unknown/Multiple | Failure: Runtime crash Difficulty: Unknown |Testcase: Blockedby:|Blocking: Related:| -+-- Comment(by bgamari): Just to ensure this detail isn't lost, I've been using BayesStack commit 6df883ec0ac8859cd7422ab2184be620fd72c63a to reproduce this issue. Do folks think it would be practical to try bisecting this issue or would attempting this just be a waste of time? -- Ticket URL: http://hackage.haskell.org/trac/ghc/ticket/7361#comment:4 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler ___ Glasgow-haskell-bugs mailing list Glasgow-haskell-bugs@haskell.org http://www.haskell.org/mailman/listinfo/glasgow-haskell-bugs
Re: [GHC] #7361: Segmentation fault on 5f37e0c71ff4af8539c5aebc739b006b4f0c6ebf
#7361: Segmentation fault on 5f37e0c71ff4af8539c5aebc739b006b4f0c6ebf -+-- Reporter: bgamari | Owner: Type: bug | Status: new Priority: highest | Milestone: 7.8.1 Component: Compiler | Version: 7.7 Keywords:| Os: Unknown/Multiple Architecture: Unknown/Multiple | Failure: Runtime crash Difficulty: Unknown |Testcase: Blockedby:|Blocking: Related:| -+-- Changes (by simonmar): * priority: normal = highest * difficulty: = Unknown * version: = 7.7 * milestone: = 7.8.1 -- Ticket URL: http://hackage.haskell.org/trac/ghc/ticket/7361#comment:3 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler ___ Glasgow-haskell-bugs mailing list Glasgow-haskell-bugs@haskell.org http://www.haskell.org/mailman/listinfo/glasgow-haskell-bugs
Re: [GHC] #7361: Segmentation fault on 5f37e0c71ff4af8539c5aebc739b006b4f0c6ebf
#7361: Segmentation fault on 5f37e0c71ff4af8539c5aebc739b006b4f0c6ebf
--+-
Reporter: bgamari | Owner:
Type: bug | Status: new
Priority: normal| Component: Compiler
Version:| Keywords:
Os: Unknown/Multiple | Architecture: Unknown/Multiple
Failure: Runtime crash | Testcase:
Blockedby:| Blocking:
Related:|
--+-
Comment(by bgamari):
After playing around a bit with various build options and ensuring object
and interface files were cleaned up, I managed to get some reasonable
output from gdb (with -dcore-lint -debug).
The backtrace is,
{{{
Program received signal SIGSEGV, Segmentation fault.
0x7fffec554b6c in LOOKS_LIKE_INFO_PTR_NOT_NULL
(p=12002426983225102154) at includes/rts/storage/ClosureMacros.h:248
248 return info-type != INVALID_OBJECT info-type
N_CLOSURE_TYPES;
Missing separate debuginfos, use: debuginfo-install
glibc-2.12-1.80.el6_3.5.x86_64 gmp-4.3.1-7.el6_2.2.x86_64
(gdb) bt
#0 0x7fffec554b6c in LOOKS_LIKE_INFO_PTR_NOT_NULL
(p=12002426983225102154) at includes/rts/storage/ClosureMacros.h:248
#1 0x7fffec554bb7 in LOOKS_LIKE_INFO_PTR (p=12002426983225102154) at
includes/rts/storage/ClosureMacros.h:253
#2 0x7fffec554bec in LOOKS_LIKE_CLOSURE_PTR (p=0x7fffe624a418) at
includes/rts/storage/ClosureMacros.h:258
#3 0x7fffec55532e in evacuate (p=0x7fffe629a028) at rts/sm/Evac.c:371
#4 0x7fffec55d049 in scavenge_mut_arr_ptrs (a=0x7fffe629a000) at
rts/sm/Scav.c:125
#5 0x7fffec55de28 in scavenge_block (bd=0x7fffe6202680) at
rts/sm/Scav.c:617
#6 0x7fffec55faae in scavenge_find_work () at rts/sm/Scav.c:1791
#7 0x7fffec55fba9 in scavenge_loop () at rts/sm/Scav.c:1867
#8 0x7fffec557db2 in scavenge_until_all_done () at rts/sm/GC.c:999
#9 0x7fffec556c7e in GarbageCollect (collect_gen=1,
do_heap_census=rtsFalse, gc_type=0, cap=0x7fffec791100) at rts/sm/GC.c:392
#10 0x7fffec544289 in scheduleDoGC (pcap=0x7fffdff0,
task=0x63fce0, force_major=rtsFalse) at rts/Schedule.c:1667
#11 0x7fffec5437dc in schedule (initialCapability=0x7fffec791100,
task=0x63fce0) at rts/Schedule.c:582
#12 0x7fffec544bf3 in scheduleWaitThread (tso=0x7fffe6305390, ret=0x0,
pcap=0x7fffe0d0) at rts/Schedule.c:2368
#13 0x7fffec53e62a in rts_evalLazyIO (cap=0x7fffe0d0, p=0x624730,
ret=0x0) at rts/RtsAPI.c:497
#14 0x7fffec5412ff in real_main () at rts/RtsMain.c:63
#15 0x7fffec5413f4 in hs_main (argc=1, argv=0x7fffe248,
main_closure=0x624730, rts_config=...) at rts/RtsMain.c:114
#16 0x004231ef in main (argc=1, argv=0x7fffe248) at
/tmp/ghc9240_0/ghc9240_0.c:7
}}}
--
Ticket URL: http://hackage.haskell.org/trac/ghc/ticket/7361#comment:1
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Re: [GHC] #7361: Segmentation fault on 5f37e0c71ff4af8539c5aebc739b006b4f0c6ebf
#7361: Segmentation fault on 5f37e0c71ff4af8539c5aebc739b006b4f0c6ebf
--+-
Reporter: bgamari | Owner:
Type: bug | Status: new
Priority: normal| Component: Compiler
Version:| Keywords:
Os: Unknown/Multiple | Architecture: Unknown/Multiple
Failure: Runtime crash | Testcase:
Blockedby:| Blocking:
Related:|
--+-
Comment(by bgamari):
When compiling with -dcore-lint -debug -O, I see the following output from
the compiler,
{{{
*** Core Lint warnings : in result of Desugar (after optimization) ***
{-# LINE 26 BayesStack/Models/Topic/Types.hs #-}: Warning:
[RHS of $c/=_a1cN :: BayesStack.Models.Topic.Types.Edge
- BayesStack.Models.Topic.Types.Edge -
GHC.Types.Bool]
INLINE binder is (non-rule) loop breaker: $c/=_a1cN
}}}
gdb also gives me a slightly different stack trace,
{{{
Program received signal SIGSEGV, Segmentation fault.
0x7fffec55f136 in scavenge_mutable_list (bd=0x7fffe6202880,
gen=0x6379e8) at rts/sm/Scav.c:1353
1353switch (get_itbl((StgClosure *)p)-type) {
Missing separate debuginfos, use: debuginfo-install
glibc-2.12-1.80.el6_3.5.x86_64 gmp-4.3.1-7.el6_2.2.x86_64
(gdb) bt
#0 0x7fffec55f136 in scavenge_mutable_list (bd=0x7fffe6202880,
gen=0x6379e8) at rts/sm/Scav.c:1353
#1 0x7fffec55f328 in scavenge_capability_mut_lists
(cap=0x7fffec791100) at rts/sm/Scav.c:1427
#2 0x7fffec556acb in GarbageCollect (collect_gen=0,
do_heap_census=rtsFalse, gc_type=0, cap=0x7fffec791100) at rts/sm/GC.c:343
#3 0x7fffec544289 in scheduleDoGC (pcap=0x7fffdff0,
task=0x645ce0, force_major=rtsFalse) at rts/Schedule.c:1667
#4 0x7fffec5437dc in schedule (initialCapability=0x7fffec791100,
task=0x645ce0) at rts/Schedule.c:582
#5 0x7fffec544bf3 in scheduleWaitThread (tso=0x7fffe6305390, ret=0x0,
pcap=0x7fffe0d0) at rts/Schedule.c:2368
#6 0x7fffec53e62a in rts_evalLazyIO (cap=0x7fffe0d0, p=0x62c260,
ret=0x0) at rts/RtsAPI.c:497
#7 0x7fffec5412ff in real_main () at rts/RtsMain.c:63
#8 0x7fffec5413f4 in hs_main (argc=1, argv=0x7fffe248,
main_closure=0x62c260, rts_config=...) at rts/RtsMain.c:114
#9 0x0042aa03 in main (argc=1, argv=0x7fffe248) at
/tmp/ghc9328_0/ghc9328_0.c:7
}}}
--
Ticket URL: http://hackage.haskell.org/trac/ghc/ticket/7361#comment:2
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[GHC] #7361: Segmentation fault on 5f37e0c71ff4af8539c5aebc739b006b4f0c6ebf
#7361: Segmentation fault on 5f37e0c71ff4af8539c5aebc739b006b4f0c6ebf --+- Reporter: bgamari | Owner: Type: bug | Status: new Priority: normal| Component: Compiler Version:| Keywords: Os: Unknown/Multiple | Architecture: Unknown/Multiple Failure: Runtime crash | Testcase: Blockedby:| Blocking: Related:| --+- I'm experiencing a segmentation fault in previously working code compiled with GHC master (5f37e0c71ff4af8539c5aebc739b006b4f0c6ebf). This occurs with several executables in bayes-stack[1] (BenchLDA and RunST). The easiest reproduction case is BenchLDA, which can be run without any external data (although doesn't get built by the cabal file). In the case of BenchLDA, gdb says that the crash is occurring in c6FD_info which seems to fall within BayesStack.Models.Topic.Types, although -ddump-simpl doesn't seem to give any hints as to which function this is. [1] http://github.com/bgamari/bayes-stack -- Ticket URL: http://hackage.haskell.org/trac/ghc/ticket/7361 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler ___ Glasgow-haskell-bugs mailing list Glasgow-haskell-bugs@haskell.org http://www.haskell.org/mailman/listinfo/glasgow-haskell-bugs
