Re: [GHC] #2722: loop when compiling with -O option with ghc-6.10.0.20081019
#2722: loop when compiling with -O option with ghc-6.10.0.20081019 -+-- Reporter: uwe | Owner: Type: bug | Status: closed Priority: normal | Milestone: 7.2.1 Component: libraries (other) |Version: 7.0.1 Resolution: invalid | Keywords: arrows Testcase: tyepcheck/should_run/T2722 | Blockedby: Difficulty: Unknown | Os: Linux Blocking: | Architecture: x86_64 (amd64) Failure: Runtime crash | -+-- Changes (by igloo): * status: new = closed * resolution: = invalid Comment: Ah, you mean there is no bug in the arrow library after all? OK, thanks for looking into it and letting us know; I'll close this ticket again then. -- Ticket URL: http://hackage.haskell.org/trac/ghc/ticket/2722#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] #2722: loop when compiling with -O option with ghc-6.10.0.20081019
#2722: loop when compiling with -O option with ghc-6.10.0.20081019 -+-- Reporter: uwe | Owner: simonpj Type: bug | Status: closed Priority: normal | Milestone: 7.0.3 Component: libraries (other) |Version: 7.0.1 Resolution: invalid | Keywords: arrows Testcase: tyepcheck/should_run/T2722 | Blockedby: Difficulty: Unknown | Os: Linux Blocking: | Architecture: x86_64 (amd64) Failure: Runtime crash | -+-- Changes (by litoh): * status: infoneeded = closed * resolution: = invalid -- Ticket URL: http://hackage.haskell.org/trac/ghc/ticket/2722#comment:21 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] #2722: loop when compiling with -O option with ghc-6.10.0.20081019
#2722: loop when compiling with -O option with ghc-6.10.0.20081019 -+-- Reporter: uwe | Owner: Type: bug | Status: new Priority: normal | Milestone: 7.0.3 Component: libraries (other) |Version: 7.0.1 Resolution: | Keywords: arrows Testcase: tyepcheck/should_run/T2722 | Blockedby: Difficulty: Unknown | Os: Linux Blocking: | Architecture: x86_64 (amd64) Failure: Runtime crash | -+-- Changes (by igloo): * owner: simonpj = * status: closed = new * resolution: invalid = Comment: We still need to fix the rules in the library that comes with GHC, so reopening this. -- Ticket URL: http://hackage.haskell.org/trac/ghc/ticket/2722#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] #2722: loop when compiling with -O option with ghc-6.10.0.20081019
#2722: loop when compiling with -O option with ghc-6.10.0.20081019 -+-- Reporter: uwe | Owner: Type: bug | Status: new Priority: normal | Milestone: 7.0.3 Component: libraries (other) |Version: 7.0.1 Resolution: | Keywords: arrows Testcase: tyepcheck/should_run/T2722 | Blockedby: Difficulty: Unknown | Os: Linux Blocking: | Architecture: x86_64 (amd64) Failure: Runtime crash | -+-- Comment(by litoh): Turned out to be a bug in the Yampa library Concerning my test case, it was a complete red herring ;) -- Ticket URL: http://hackage.haskell.org/trac/ghc/ticket/2722#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] #2722: loop when compiling with -O option with ghc-6.10.0.20081019
#2722: loop when compiling with -O option with ghc-6.10.0.20081019
-+--
Reporter: uwe | Owner: simonpj
Type: bug | Status: infoneeded
Priority: normal | Milestone: 7.0.3
Component: libraries (other) |Version: 7.0.1
Resolution: | Keywords: arrows
Testcase: tyepcheck/should_run/T2722 | Blockedby:
Difficulty: Unknown | Os: Linux
Blocking: | Architecture: x86_64 (amd64)
Failure: Runtime crash |
-+--
Comment(by simonpj):
Harumph. It turns out that `-fno-enable-rewrite-rules` doesn't work.
This patch fixes it
{{{
* Make -fno-enable-rewrite-rules work properly
I'd failed to propagate the Opt_EnableRewriteRules flag properly,
which meant that -fno-enable-rewrite-rules didn't disable all
rewrites. This patch fixes it.
M ./compiler/simplCore/CoreMonad.lhs -4 +1
M ./compiler/simplCore/SimplCore.lhs -1 +1
M ./compiler/simplCore/SimplUtils.lhs -7 +13
M ./compiler/simplCore/Simplify.lhs -1 +2
}}}
Once that is done, T2722 works fine with `-O -fno-enable-rewrite-rules`,
and loops with plain `-O`. (You don't need to recompile the libraries to
see this effect.)
So it's definitely a rewrite rule. It seems to me very likely that it's a
similar bug to the one I tracked down at the beginning of this ticket.
It's probably not strictly a GHC bug, but still a bug in a RULE in a
library shipped with GHC is much the same from a customer point of view.
To help find it,
* `-ddump-rule-firings` will show which rules are firing
* `-ddump-rule-rewrites` will additionally show before and after
* You can comment out rules to disable them individually. (But some are
in libraries, so that will require you to recompile the library.)
Thanks for helping
Simon
--
Ticket URL: http://hackage.haskell.org/trac/ghc/ticket/2722#comment:20
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Re: [GHC] #2722: loop when compiling with -O option with ghc-6.10.0.20081019
#2722: loop when compiling with -O option with ghc-6.10.0.20081019
-+--
Reporter: uwe | Owner: simonpj
Type: bug | Status: infoneeded
Priority: normal | Milestone: 7.0.3
Component: libraries (other) |Version: 7.0.1
Resolution: | Keywords: arrows
Testcase: tyepcheck/should_run/T2722 | Blockedby:
Difficulty: Unknown | Os: Linux
Blocking: | Architecture: x86_64 (amd64)
Failure: Runtime crash |
-+--
Comment(by litoh):
{{{
$ ghc --make test.hs -o test -O2 -fno-enable-rewrite-rules -ddump-rule-
firings
Rule fired: Class op show
Rule fired: Class op arr
Rule fired: Class op first
Rule fired: concat
Rule fired: map
Rule fired: Class op arr
Rule fired: arrPrim/arrEPrim
Rule fired: unpack
Rule fired: Class op loop
$ ./test
testloop: loop
}}}
If I understood -fno-enable-rewrite-rules correctly, it should turn off
rules. Thus the bug doesn't derive from rule rewriting?
--
Ticket URL: http://hackage.haskell.org/trac/ghc/ticket/2722#comment:19
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Re: [GHC] #2722: loop when compiling with -O option with ghc-6.10.0.20081019
#2722: loop when compiling with -O option with ghc-6.10.0.20081019 -+-- Reporter: uwe | Owner: simonpj Type: bug | Status: infoneeded Priority: normal | Milestone: 7.0.3 Component: libraries (other) |Version: 7.0.1 Resolution: | Keywords: arrows Testcase: tyepcheck/should_run/T2722 | Blockedby: Difficulty: Unknown | Os: Linux Blocking: | Architecture: x86_64 (amd64) Failure: Runtime crash | -+-- Comment(by simonpj): OK, my comment with the patch Major refactoring of the type inference engine is a complete red herring; this ticket is about something different. The original bug turned out to be that a RULE in `Control.Arrow` was incompatible with a client's instance declaration. It's possible (probable, even) that the same thing is happening here. * Try with `-O -fno-enable-rewrite-rules` which will switch off all rewrite rules but enable other optimisations. * Try `-ddump-rule-firings` to see which rules are firing * If that is OK, try disabling rules in `Control.Arrow` to try to binary- chop your way to the offending RULE. Let me know if I can help, but currently I believe this is a library/client problem rather than a GHC one. Simon -- Ticket URL: http://hackage.haskell.org/trac/ghc/ticket/2722#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] #2722: loop when compiling with -O option with ghc-6.10.0.20081019
#2722: loop when compiling with -O option with ghc-6.10.0.20081019
-+--
Reporter: uwe | Owner: simonpj
Type: bug | Status: infoneeded
Priority: normal | Milestone: 7.0.3
Component: libraries (other) |Version: 7.0.1
Resolution: | Keywords: arrows
Testcase: tyepcheck/should_run/T2722 | Blockedby:
Difficulty: Unknown | Os: Linux
Blocking: | Architecture: x86_64 (amd64)
Failure: Runtime crash |
-+--
Comment(by igloo):
I've attached a dependency-free testcase:
{{{
$ ghc --make -O T2722 -fforce-recomp ./T2722; ghc --make -O0 T2722
-fforce-recomp ./T2722
[1 of 1] Compiling Main ( T2722.hs, T2722.o )
Linking T2722 ...
T2722: loop
[1 of 1] Compiling Main ( T2722.hs, T2722.o )
Linking T2722 ...
[[(testObj,1)],[(testObj,1)]]
}}}
--
Ticket URL: http://hackage.haskell.org/trac/ghc/ticket/2722#comment:17
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Re: [GHC] #2722: loop when compiling with -O option with ghc-6.10.0.20081019
#2722: loop when compiling with -O option with ghc-6.10.0.20081019 -+-- Reporter: uwe | Owner: simonpj Type: bug | Status: infoneeded Priority: normal | Milestone: 7.0.3 Component: libraries (other) |Version: 7.0.1 Resolution: | Keywords: arrows Testcase: tyepcheck/should_run/T2722 | Blockedby: Difficulty: Unknown | Os: Linux Blocking: | Architecture: x86_64 (amd64) Failure: Runtime crash | -+-- Comment(by litoh): The problem remains, here's what I did: Installed new darcs to avoid sleeping: $ darcs -v 2.5.1 (release) I followed the GHC build guides at http://hackage.haskell.org/trac/ghc/wiki/Building/Hacking (with --no-cache option) $ darcs get --lazy --no-cache http://darcs.haskell.org/ghc $ ./darcs-all --testsuite get in mk/build.mk: BuidlFlavour = prof $ perl boot $ ./configure --with-ghc=/usr/local/bin/ghc-7.0.1.20110217 (I had to recompile for profiling support and define an older GHC build. I used the current RC build) $ make -j2 $ make install $ ghc --version The Glorious Glasgow Haskell Compilation System, version 7.1.20110223 $ cabal install yampa $ ghc --make Test.hs -o test -O2 -fforce-recomp test: loop :/ -- Ticket URL: http://hackage.haskell.org/trac/ghc/ticket/2722#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] #2722: loop when compiling with -O option with ghc-6.10.0.20081019
#2722: loop when compiling with -O option with ghc-6.10.0.20081019 -+-- Reporter: uwe | Owner: simonpj Type: bug | Status: infoneeded Priority: normal | Milestone: 7.0.3 Component: libraries (other) |Version: 7.0.1 Resolution: | Keywords: arrows Testcase: tyepcheck/should_run/T2722 | Blockedby: Difficulty: Unknown | Os: Linux Blocking: | Architecture: x86_64 (amd64) Failure: Runtime crash | -+-- Comment(by simonpj): Ah, yes, I recall this darcs-freezing thing happened to me to. What fixed it was adding --no-cache, I think. try that. As to your build error, you have done `./darcs-all get` haven't you? I think you'd be better off with HEAD than with something from 10 Jan. Simon -- Ticket URL: http://hackage.haskell.org/trac/ghc/ticket/2722#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] #2722: loop when compiling with -O option with ghc-6.10.0.20081019
#2722: loop when compiling with -O option with ghc-6.10.0.20081019 -+-- Reporter: uwe | Owner: simonpj Type: bug | Status: infoneeded Priority: normal | Milestone: 7.0.3 Component: libraries (other) |Version: 7.0.1 Resolution: | Keywords: arrows Testcase: tyepcheck/should_run/T2722 | Blockedby: Difficulty: Unknown | Os: Linux Blocking: | Architecture: x86_64 (amd64) Failure: Runtime crash | -+-- Comment(by litoh): I really tried to help but after 6 hrs of unsuccessfully compiling ghc- HEAD-2011-01-10-ghc.tar.bz2 on Ubuntu x64 Linux I gave up. Sorry. Maybe there is a better place to discuss this but I get the following error when doing $ ghc/make Configuring haddock-2.8.0... make[1]: *** No rule to make target `libraries/dph/ghc.mk'. Stop. make: *** [all] Error 2 Another problem appears to be that darcs is constantly freezing $ ./darcs-all get Copying pristine 486 done, 6 queued. legacy $ darcs -v 2.4.4 (release) -- Ticket URL: http://hackage.haskell.org/trac/ghc/ticket/2722#comment:14 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] #2722: loop when compiling with -O option with ghc-6.10.0.20081019
#2722: loop when compiling with -O option with ghc-6.10.0.20081019
-+--
Reporter: uwe | Owner: simonpj
Type: bug | Status: infoneeded
Priority: normal | Milestone: 7.0.3
Component: libraries (other) |Version: 7.0.1
Resolution: | Keywords: arrows
Testcase: tyepcheck/should_run/T2722 | Blockedby:
Difficulty: Unknown | Os: Linux
Blocking: | Architecture: x86_64 (amd64)
Failure: Runtime crash |
-+--
Changes (by simonpj):
* status: new = infoneeded
* testcase: = tyepcheck/should_run/T2722
Comment:
OK I think this one is properly fixed now
{{{
Wed Jan 12 06:56:04 PST 2011 simo...@microsoft.com
* Major refactoring of the type inference engine
This patch embodies many, many changes to the contraint solver, which
make it simpler, more robust, and more beautiful. But it has taken
me ages to get right. The forcing issue was some obscure programs
involving recursive dictionaries, but these eventually led to a
massive refactoring sweep.
Main changes are:
* No more frozen errors in the monad. Instead insoluble
constraints are now part of the WantedConstraints type.
* The WantedConstraint type is a product of bags, instead of (as
before) a bag of sums. This eliminates a good deal of tagging and
untagging.
* This same WantedConstraints data type is used
- As the way that constraints are gathered
- As a field of an implication constraint
- As both argument and result of solveWanted
- As the argument to reportUnsolved
* We do not generate any evidence for Derived constraints. They are
purely there to allow impovement by unifying unification
variables.
* In consequence, nothing is ever *rewritten* by a Derived
constraint. This removes, by construction, all the horrible
potential recursive-dictionary loops that were making us tear our
hair out. No more isGoodRecEv search either. Hurrah!
* We add the superclass Derived constraints during canonicalisation,
after checking for duplicates. So fewer superclass constraints
are generated than before.
* Skolem tc-tyvars no longer carry SkolemInfo. Instead, the
SkolemInfo lives in the GivenLoc of the Implication, where it
can be tidied, zonked, and substituted nicely. This alone is
a major improvement.
* Tidying is improved, so that we tend to get t1, t2, t3, rather
than t1, t11, t111, etc
Moreover, unification variables are always printed with a digit
(thus a0, a1, etc), so that plain 'a' is available for a skolem
arising from a type signature etc. In this way,
(a) We quietly say which variables are unification variables,
for those who know and care
(b) Types tend to get printed as the user expects. If he writes
f :: a - a
f = ...blah...
then types involving 'a' get printed with 'a', rather than
some tidied variant.
* There are significant improvements in error messages, notably
in the Cannot deduce X from Y messages.
M ./compiler/basicTypes/Name.lhs -1 +1
M ./compiler/basicTypes/OccName.lhs -2 +4
M ./compiler/basicTypes/Var.lhs -1 +4
M ./compiler/ghci/RtClosureInspect.hs -5 +2
M ./compiler/main/HscTypes.lhs -5 +9
M ./compiler/main/InteractiveEval.hs -18 +32
M ./compiler/typecheck/FamInst.lhs -2 +1
M ./compiler/typecheck/Inst.lhs -42 +113
M ./compiler/typecheck/TcArrows.lhs -1 +1
M ./compiler/typecheck/TcBinds.lhs -16 +9
M ./compiler/typecheck/TcCanonical.lhs -110 +162
M ./compiler/typecheck/TcClassDcl.lhs -3 +2
M ./compiler/typecheck/TcEnv.lhs +1
M ./compiler/typecheck/TcErrors.lhs -298 +248
M ./compiler/typecheck/TcExpr.lhs -3 +8
M ./compiler/typecheck/TcHsSyn.lhs -1 +1
M ./compiler/typecheck/TcHsType.lhs -2 +2
M ./compiler/typecheck/TcInstDcls.lhs -23 +14
M ./compiler/typecheck/TcInteract.lhs -336 +304
M ./compiler/typecheck/TcMType.lhs -79 +119
M ./compiler/typecheck/TcMatches.lhs -1 +1
M ./compiler/typecheck/TcPat.lhs -6 +6
M ./compiler/typecheck/TcRnDriver.lhs -4 +16
M ./compiler/typecheck/TcRnMonad.lhs -7 +22
M ./compiler/typecheck/TcRnTypes.lhs -103 +305
M ./compiler/typecheck/TcRules.lhs -2 +3
M ./compiler/typecheck/TcSMonad.lhs -270 +82
M ./compiler/typecheck/TcSimplify.lhs -378 +427
M ./compiler/typecheck/TcSplice.lhs -9 +10
M ./compiler/typecheck/TcType.lhs
Re: [GHC] #2722: loop when compiling with -O option with ghc-6.10.0.20081019
#2722: loop when compiling with -O option with ghc-6.10.0.20081019 +--- Reporter: uwe| Owner: simonpj Type: bug| Status: new Priority: normal | Milestone: 7.0.3 Component: libraries (other) |Version: 7.0.1 Resolution: | Keywords: arrows Testcase: | Blockedby: Difficulty: Unknown| Os: Linux Blocking: | Architecture: x86_64 (amd64) Failure: Runtime crash | +--- Changes (by simonmar): * owner: = simonpj -- Ticket URL: http://hackage.haskell.org/trac/ghc/ticket/2722#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] #2722: loop when compiling with -O option with ghc-6.10.0.20081019
#2722: loop when compiling with -O option with ghc-6.10.0.20081019 +--- Reporter: uwe| Owner: Type: bug| Status: new Priority: normal | Milestone: 7.0.3 Component: libraries (other) |Version: 7.0.1 Resolution: | Keywords: arrows Testcase: | Blockedby: Difficulty: Unknown| Os: Linux Blocking: | Architecture: x86_64 (amd64) Failure: Runtime crash | +--- Changes (by igloo): * milestone: Not GHC = 7.0.3 -- Ticket URL: http://hackage.haskell.org/trac/ghc/ticket/2722#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] #2722: loop when compiling with -O option with ghc-6.10.0.20081019
#2722: loop when compiling with -O option with ghc-6.10.0.20081019
+---
Reporter: uwe| Owner:
Type: bug| Status: new
Priority: normal | Milestone: Not GHC
Component: libraries (other) |Version: 7.0.1
Resolution: | Keywords: arrows
Testcase: | Blockedby:
Difficulty: Unknown| Os: Linux
Blocking: | Architecture: x86_64 (amd64)
Failure: Runtime crash |
+---
Changes (by litoh):
* status: closed = new
* failure: = Runtime crash
* version: 6.10.1 = 7.0.1
* resolution: fixed =
* architecture: x86 = x86_64 (amd64)
Comment:
I'm getting the same error with another Arrow library (FRP.Yampa). What's
strange though is that the error disappears under certain circumstances:
# use Bool instead of Event () for input type
# use Int instead of (String, Int) for output type
# -
# inline constant function
WTF? :)
{{{
{-# LANGUAGE Arrows #-}
module Main (main) where
import FRP.Yampa
type ObjIn = Event () -- loop #1
--type ObjIn = Bool -- no loop #1
type ObjOut = (String, Int) -- loop #2
--type ObjOut = Int -- no loop #2
type GameObj = SF ObjIn ObjOut
testObj :: GameObj
testObj = proc hit - do
returnA - (testObj, 1) -- loop #2
--returnA - 1-- no loop #2
process :: [GameObj] - SF () [ObjOut]
process objs = proc _ - do
rec
gamestate - par logic objs
- gamestate -- loop #3 (recursive definition!)
--- [] -- no loop #3
returnA - gamestate
logic :: [ObjOut] - [sf] - [(ObjIn, sf)]
logic gamestate objs = map route objs
where
route obj =
(if null (foo gamestate) then NoEvent else NoEvent, obj) -- loop
#1
--(if null (foo gamestate) then False else False, obj) -- no loop
#1
foo :: [ObjOut] - [ObjOut]
foo [] = []
foo objs = concat (collisions objs)
where
collisions [] = []
collisions (out:objs') =
[[out, out'] | out' - objs, out `collide` out'] -- loop #4
--[[out, out'] | out' - objs, True] -- no loop #4
collide :: ObjOut - ObjOut - Bool
collide (_, p) (_, p') = True -- loop #2
--collide p p' = True -- no loop #2
main :: IO ()
main = do
putStrLn . show $ embed (process [testObj]) ((), [(1.0, Nothing)])
}}}
--
Ticket URL: http://hackage.haskell.org/trac/ghc/ticket/2722#comment:10
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Re: [GHC] #2722: loop when compiling with -O option with ghc-6.10.0.20081019
#2722: loop when compiling with -O option with ghc-6.10.0.20081019 ---+ Reporter: uwe| Owner: Type: bug| Status: closed Priority: normal | Milestone: Not GHC Component: libraries (other) |Version: 6.10.1 Severity: normal | Resolution: fixed Keywords: arrows | Difficulty: Unknown Testcase: | Architecture: x86 Os: Linux | ---+ Changes (by ross): * status: new = closed * resolution: = fixed Comment: It never occurred to me before that using a valid equation as a rule could change the semantics of a recursive definition, but it's obvious in retrospect. So with the Category split, this rule has to go, and I've pushed a patch to delete it. -- Ticket URL: http://hackage.haskell.org/trac/ghc/ticket/2722#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] #2722: loop when compiling with -O option with ghc-6.10.0.20081019
#2722: loop when compiling with -O option with ghc-6.10.0.20081019
---+
Reporter: uwe| Owner:
Type: bug| Status: new
Priority: normal | Milestone: Not GHC
Component: libraries (other) |Version: 6.10.1
Severity: normal | Resolution:
Keywords: arrows | Difficulty: Unknown
Testcase: | Architecture: x86
Os: Linux |
---+
Comment (by simonpj):
Well the `Arrow` class in `Control.Arrow` is immediately followed by a
whole bunch of rules:
{{{
{-# RULES
identity
arr id = id
compose/arr forall f g .
(arr f) . (arr g) = arr (f . g)
first/arr forall f .
first (arr f) = arr (first f)
second/arrforall f .
second (arr f) = arr (second f)
product/arr forall f g .
arr f *** arr g = arr (f *** g)
fanout/arrforall f g .
arr f arr g = arr (f g)
compose/first forall f g .
(first f) . (first g) = first (f . g)
compose/second forall f g .
(second f) . (second g) = second (f . g)
#-}
}}}
If you are saying that they are not valid in general (eg you say the first
is valid only for `(-)`), then these rules had better be speicialised for
the types they work for.
Can you and Ross discuss this, and figure out what to do? It's not a GHC
issue any more: rather a question of the Arrow/Category library design.
Simon
PS: Yes if you define `id` explicitly that ought to be ok. But remember
that the RULE `arr id --- id` is still going to apply (perhaps bogusly?)
at all arrows. So you want to do more than work around the problem.
--
Ticket URL: http://hackage.haskell.org/trac/ghc/ticket/2722#comment:8
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Re: [GHC] #2722: loop when compiling with -O option with ghc-6.10.0.20081019
#2722: loop when compiling with -O option with ghc-6.10.0.20081019 ---+ Reporter: uwe| Owner: Type: bug| Status: new Priority: high | Milestone: 6.10.1 Component: Compiler |Version: 6.10.1 Severity: normal | Resolution: Keywords: Optimization Loop | Difficulty: Unknown Testcase: | Architecture: x86 Os: Linux | ---+ Comment (by simonpj): That's a big program! Can you say why you suspect `id` and `(.)`, and/or `Control.Arrow.*`? -- Ticket URL: http://hackage.haskell.org/trac/ghc/ticket/2722#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] #2722: loop when compiling with -O option with ghc-6.10.0.20081019
#2722: loop when compiling with -O option with ghc-6.10.0.20081019
---+
Reporter: uwe| Owner:
Type: bug| Status: new
Priority: high | Milestone: 6.10.1
Component: Compiler |Version: 6.10.1
Severity: normal | Resolution:
Keywords: Optimization Loop | Difficulty: Unknown
Testcase: | Architecture: x86
Os: Linux |
---+
Comment (by igloo):
I've attached a single module case:
{{{
$ ghc -fforce-recomp --make HXmlParser.hs -Wall ./HXmlParser
[1 of 1] Compiling Main ( HXmlParser.hs, HXmlParser.o )
Linking HXmlParser ...
Foo 1
Foo 2
HXmlParser: XXX
}}}
{{{
$ ghc -fforce-recomp --make HXmlParser.hs -O -Wall ./HXmlParser
[1 of 1] Compiling Main ( HXmlParser.hs, HXmlParser.o )
Linking HXmlParser ...
Foo 1
HXmlParser: loop
}}}
--
Ticket URL: http://hackage.haskell.org/trac/ghc/ticket/2722#comment:4
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Re: [GHC] #2722: loop when compiling with -O option with ghc-6.10.0.20081019
#2722: loop when compiling with -O option with ghc-6.10.0.20081019
---+
Reporter: uwe| Owner:
Type: bug| Status: new
Priority: high | Milestone: 6.10.1
Component: Compiler |Version: 6.10.1
Severity: normal | Resolution:
Keywords: Optimization Loop | Difficulty: Unknown
Testcase: | Architecture: x86
Os: Linux |
---+
Comment (by simonpj):
OK I know what is happening. Sigh.
I boiled it down still more:
{{{
module Foo (main, arid1, arid2) where
import Prelude hiding (id, (.))
import qualified Prelude
import Control.Category
import Control.Arrow
import System.IO
import Debug.Trace
main = runXIOState arid1-- Loop with arid1
-- Works with arid2
arid1 :: Arrow m = m a a
arid1 = arr id
arid2 :: Arrow m = m a a
arid2 = arr Prelude.id
runXIOState :: IOSLA () c - IO [c]
runXIOState f = runIOSLA f ()
newtype IOSLA a b = IOSLA { runIOSLA :: a - IO [b] }
instance Arrow IOSLA where
arr f = IOSLA $ \ x - return [f x]
instance Category IOSLA where
id = arr id
-- arr :: Arrow m = (b-c) - m b c
-- id :: Category m = m b b
-- (arr id) :: Arrow m = m a a
}}}
What is happening is this.
* In `Control.Arrow` we find the following rewrite rule
{{{
{-# RULES identity arr id = id
}}}
* But, as you see above, `id` is defined to be `arr id`.
So the result is (unsurprisingly) a loop.
I'm not sure whether the fault lies with the person who wrote the RULE in
`Control.Arrow`, or the person who wrote the instance of IOSLA above.
(The instance does look suspicious, because `Category` is a superclass of
`Arrow`, and yet uses the arrow `arr` method to define `id`.)
Very tricky to track down. At all events I say that GHC is not at fault.
I'm leaving this open because someone should
* Decide whether the rules in `Control.Arrow` are valid in general.
* If so, write some documentation somewhere about the constraints that
these rules impose on instance declarations.
Simon
--
Ticket URL: http://hackage.haskell.org/trac/ghc/ticket/2722#comment:5
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Re: [GHC] #2722: loop when compiling with -O option with ghc-6.10.0.20081019
#2722: loop when compiling with -O option with ghc-6.10.0.20081019 ---+ Reporter: uwe| Owner: Type: bug| Status: new Priority: high | Milestone: 6.10.1 Component: Compiler |Version: 6.10.1 Severity: normal | Resolution: Keywords: Optimization Loop | Difficulty: Unknown Testcase: | Architecture: x86 Os: Linux | ---+ Comment (by uwe): I've prepared a tar archive with all sources needed to reproduce the error. The URL is http://www.fh-wedel.de/~si/HXmlToolbox/hxt-ghc10-error.tar.gz Please untar the archive, cd into hxt-ghc10 and run make error. This will cd into examples/arrows/hparser, compile the test prog with -O0 and execute a simple test run. Then the build is repeated but with -O and the test prog issues loop. There are a lot of sources, that shouldn't have any influence on this error. Interesting modules could be the Control.Arrow.* modules. -- Ticket URL: http://hackage.haskell.org/trac/ghc/ticket/2722#comment:2 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] #2722: loop when compiling with -O option with ghc-6.10.0.20081019
#2722: loop when compiling with -O option with ghc-6.10.0.20081019 ---+ Reporter: uwe| Owner: Type: bug| Status: new Priority: high | Milestone: 6.10.1 Component: Compiler |Version: 6.10.1 Severity: normal | Resolution: Keywords: Optimization Loop | Difficulty: Unknown Testcase: | Architecture: x86 Os: Linux | ---+ Changes (by igloo): * priority: normal = high * difficulty: = Unknown * milestone: = 6.10.1 Comment: A tar archive would be very useful, thanks! -- Ticket URL: http://hackage.haskell.org/trac/ghc/ticket/2722#comment:1 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
[GHC] #2722: loop when compiling with -O option with ghc-6.10.0.20081019
#2722: loop when compiling with -O option with ghc-6.10.0.20081019
--+-
Reporter: uwe| Owner:
Type: bug| Status: new
Priority: normal | Component: Compiler
Version: 6.10.1 |Severity: normal
Keywords: Optimization Loop |Testcase:
Architecture: x86| Os: Linux
--+-
When trying to compile HXT with ghc-6.10 rc1 all examples,
even the simplest ones give the following result. Here is an example:
{{{
[EMAIL PROTECTED]:~/haskell/hxt-ghc10/examples/arrows/hparser ./HXmlParser
example1.xml
HXmlParser: loop
}}}
this only occurs, when compiling with -O (or -O2). When
compiling whithout any optimizaions, the programs run as
expected
Here is a more complete log of one example
The running example without -O
{{{
[EMAIL PROTECTED]:~/haskell/hxt-ghc10/examples/arrows/hparser ghc --version
The Glorious Glasgow Haskell Compilation System, version 6.10.0.20081019
[EMAIL PROTECTED]:~/haskell/hxt-ghc10/examples/arrows/hparser ghc-pkg list
/home/theo/lib/ghc-6.10.0.20081019/./package.conf:
Cabal-1.6.0.1, HUnit-1.2.0.2, QuickCheck-1.2.0.0, array-0.2.0.0,
base-3.0.3.0, base-4.0.0.0, bytestring-0.9.1.4, containers-0.2.0.0,
curl-1.3.2.1, directory-1.0.0.2, (dph-base-0.3), (dph-par-0.3),
(dph-prim-interface-0.3), (dph-prim-par-0.3), (dph-prim-seq-0.3),
(dph-seq-0.3), filepath-1.1.0.1, (ghc-6.10.0.20081019),
ghc-prim-0.1.0.0, haddock-2.2.2, haskell-src-1.0.1.3,
haskell98-1.0.1.0, hpc-0.5.0.2, html-1.0.1.2, hxt-8.2.0,
integer-0.1.0.0, mtl-1.1.0.2, network-2.2.0.0, old-locale-1.0.0.1,
old-time-1.0.0.1, packedstring-0.1.0.1, parallel-1.0.0.1,
parsec-2.1.0.1, pretty-1.0.1.0, process-1.0.1.0, random-1.0.0.1,
regex-base-0.72.0.2, regex-compat-0.71.0.1, regex-posix-0.72.0.3,
rts-1.0, stm-2.1.1.1, syb-0.1.0.0, tagsoup-0.6,
template-haskell-2.3.0.0, time-1.1.2.2, unix-2.3.1.0,
xhtml-3000.2.0.1
[EMAIL PROTECTED]:~/haskell/hxt-ghc10/examples/arrows/hparser find
../../../src
-name '*.hi' | xargs rm -f
[EMAIL PROTECTED]:~/haskell/hxt-ghc10/examples/arrows/hparser make local
GHCFLAGS=-Wall
ghc --make -o ./HXmlParser -Wall -fglasgow-exts -ignore-package hxt
-i../../../src ./HXmlParser.hs
[ 1 of 112] Compiling Text.XML.HXT.XPath.XPathKeywords (
../../../src/Text/XML/HXT/XPath/XPathKeywords.hs,
../../../src/Text/XML/HXT/XPath/XPathKeywords.o )
[ 2 of 112] Compiling Text.XML.HXT.IO.GetFILE (
../../../src/Text/XML/HXT/IO/GetFILE.hs,
../../../src/Text/XML/HXT/IO/GetFILE.o )
[ 3 of 112] Compiling Text.XML.HXT.DTDValidation.RE (
../../../src/Text/XML/HXT/DTDValidation/RE.hs,
../../../src/Text/XML/HXT/DTDValidation/RE.o )
...
[111 of 112] Compiling Text.XML.HXT.Arrow (
../../../src/Text/XML/HXT/Arrow.hs, ../../../src/Text/XML/HXT/Arrow.o )
[112 of 112] Compiling Main ( HXmlParser.hs, HXmlParser.o )
Linking ./HXmlParser ...
[EMAIL PROTECTED]:~/haskell/hxt-ghc10/examples/arrows/hparser ./HXmlParser
example1.xml
?xml version=1.0 encoding=UTF-8?
?pi value=a processing instruction?a att1=test äöüß test
att2=root
b btt2=b1 btt3=root/
cühello world äöüß test/cü
/a
}}}
The same with -O
{{{
[EMAIL PROTECTED]:~/haskell/hxt-ghc10/examples/arrows/hparser
[EMAIL PROTECTED]:~/haskell/hxt-ghc10/examples/arrows/hparser find
../../../src
-name '*.hi' | xargs rm -f
[EMAIL PROTECTED]:~/haskell/hxt-ghc10/examples/arrows/hparser make clean
rm -f ./HXmlParser *.o *.hi
[EMAIL PROTECTED]:~/haskell/hxt-ghc10/examples/arrows/hparser make local
GHCFLAGS=-Wall -O
ghc --make -o ./HXmlParser -Wall -O -fglasgow-exts -ignore-package hxt
-i../../../src ./HXmlParser.hs
[ 1 of 112] Compiling Text.XML.HXT.XPath.XPathKeywords (
../../../src/Text/XML/HXT/XPath/XPathKeywords.hs,
../../../src/Text/XML/HXT/XPath/XPathKeywords.o )
[ 2 of 112] Compiling Text.XML.HXT.IO.GetFILE (
../../../src/Text/XML/HXT/IO/GetFILE.hs,
../../../src/Text/XML/HXT/IO/GetFILE.o )
[ 3 of 112] Compiling Text.XML.HXT.DTDValidation.RE (
../../../src/Text/XML/HXT/DTDValidation/RE.hs,
../../../src/Text/XML/HXT/DTDValidation/RE.o )
[ 4 of 112] Compiling Text.XML.HXT.RelaxNG.Unicode.Blocks (
../../../src/Text/XML/HXT/RelaxNG/Unicode/Blocks.hs,
../../../src/Text/XML/HXT/RelaxNG/Unicode/Blocks.o )
...
[111 of 112] Compiling Text.XML.HXT.Arrow (
../../../src/Text/XML/HXT/Arrow.hs, ../../../src/Text/XML/HXT/Arrow.o )
[112 of 112] Compiling Main ( HXmlParser.hs, HXmlParser.o )
Linking ./HXmlParser ...
[EMAIL PROTECTED]:~/haskell/hxt-ghc10/examples/arrows/hparser ./HXmlParser
example1.xml
HXmlParser: loop
}}}
The only difference is the -O.
My guess is, that there could be problems with
the overloaded version of id and . (function
