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Re: [GHC] #7483: Broken Read instance for Data.Fixed ("no parse" in legitimate cases).
by GHC 24 Jun '14

24 Jun '14

#7483: Broken Read instance for Data.Fixed ("no parse" in legitimate cases). ------------------------------------------------+-------------------------- Reporter: navaati | Owner: Type: bug | Status: closed Priority: normal | Milestone: Component: libraries/base | Version: 7.6.1 Resolution: fixed | Keywords: Operating System: Unknown/Multiple | Architecture: Type of failure: Incorrect result at runtime | Unknown/Multiple Test Case: readFixed001 | Difficulty: Blocking: | Unknown | Blocked By: | Related Tickets: #4502 ------------------------------------------------+-------------------------- Comment (by Herbert Valerio Riedel <hvr@…>): In [changeset:"c1035d51edaac2f388a0630e2ad25391e7e3c1ab/ghc"]: {{{ #!CommitTicketReference repository="ghc" revision="c1035d51edaac2f388a0630e2ad25391e7e3c1ab" Fix regression in Data.Fixed Read instance (re #9231) `convertFixed` operates under the wrong assumption that `Data.Fixed.resolution` returns a base-10 exponent `e`, whereas it actually returns the power-of-10 value `10^e`. So while the code (that was introduced in 5f19f951d8 / #7483) happens to compute a correct result by coincidence, it allocates huge integer values in the process (i.e. `10^(10^e)`) which cause long computations which eventually result in out-of-memory conditions for `e`-values beyond `Data.Fixed.Milli`. A proper long-term fix would probably be to extend the `HasResolution` type-class to have a 2nd method providing the `e` value. Signed-off-by: Herbert Valerio Riedel <hvr(a)gnu.org> Differential Revision: https://phabricator.haskell.org/D25 }}} -- Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/7483#comment:3> GHC <http://www.haskell.org/ghc/> The Glasgow Haskell Compiler

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Re: [GHC] #1721: Make GHCi print the entire result of an interactive 'bind' statement
by GHC 24 Jun '14

24 Jun '14

#1721: Make GHCi print the entire result of an interactive 'bind' statement -------------------------------------+------------------------------------ Reporter: simonpj | Owner: Type: feature request | Status: closed Priority: lowest | Milestone: 7.6.2 Component: Compiler | Version: 6.6.1 Resolution: fixed | Keywords: Operating System: Unknown/Multiple | Architecture: Unknown/Multiple Type of failure: None/Unknown | Difficulty: Unknown Test Case: | Blocked By: Blocking: | Related Tickets: -------------------------------------+------------------------------------ Changes (by Artyom.Kazak): * status: new => closed * resolution: => fixed Comment: The current choice (GHCi 7.8.2) is to print nothing even when there's only one bound variable, which is consistent and avoids unpleasant surprises (as the one Ryan Ingram stumbled upon – see 1st comment). -- Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/1721#comment:15> GHC <http://www.haskell.org/ghc/> The Glasgow Haskell Compiler

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[GHC] #9047: Testsuite fails on OS X Mavericks
by GHC 24 Jun '14

24 Jun '14

#9047: Testsuite fails on OS X Mavericks ------------------------------------+--------------------------------- Reporter: goldfire | Owner: Type: bug | Status: new Priority: normal | Milestone: Component: Test Suite | Version: 7.8.2 Keywords: | Operating System: MacOS X Architecture: Unknown/Multiple | Type of failure: None/Unknown Difficulty: Unknown | Test Case: Blocked By: | Blocking: Related Tickets: | ------------------------------------+--------------------------------- Perhaps this is already well-known, but the testsuite utterly fails on Mavericks. Most tests fail because of extra output from clang. Here is a representative: {{{ Actual stderr output differs from expected: --- ./tcfail188.stderr 2014-02-07 15:28:16.000000000 -0500 +++ ./tcfail188.comp.stderr 2014-04-28 14:37:03.000000000 -0400 @@ -0,0 +1,3 @@ +clang: warning: argument unused during compilation: '-fno-stack- protector' +clang: warning: argument unused during compilation: '-D TABLES_NEXT_TO_CODE' +clang: warning: argument unused during compilation: '-I .' *** unexpected failure for tcfail188(normal) }}} Is this a local setting problem? Or is this something that can be fixed centrally? -- Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/9047> GHC <http://www.haskell.org/ghc/> The Glasgow Haskell Compiler

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[GHC] #9203: Perf regression in 7.8.2 relative to 7.6.3, possibly related to Typeable
by GHC 23 Jun '14

23 Jun '14

#9203: Perf regression in 7.8.2 relative to 7.6.3, possibly related to Typeable ------------------------------+-------------------------------------------- Reporter: simonmar | Owner: Type: bug | Status: new Priority: normal | Milestone: 7.8.3 Component: Compiler | Version: 7.8.2 Keywords: | Operating System: Unknown/Multiple Architecture: | Type of failure: Runtime performance bug Unknown/Multiple | Test Case: Difficulty: Unknown | Blocking: Blocked By: | Related Tickets: | ------------------------------+-------------------------------------------- {{{ $ git clone http://github.com/facebook/Haxl.git Cloning into 'Haxl'... remote: Counting objects: 77, done. remote: Compressing objects: 100% (65/65), done. remote: Total 77 (delta 17), reused 69 (delta 9) Unpacking objects: 100% (77/77), done. $ cd Haxl $ ghc-7.6.3 -O2 tests/Bench.hs -main-is Bench -o tests/Bench-76 [1 of 6] Compiling Haxl.Core.StateStore ( Haxl/Core/StateStore.hs, Haxl/Core/StateStore.o ) [2 of 6] Compiling Haxl.Core.Show1 ( Haxl/Core/Show1.hs, Haxl/Core/Show1.o ) [3 of 6] Compiling Haxl.Core.Util ( Haxl/Core/Util.hs, Haxl/Core/Util.o ) [4 of 6] Compiling Haxl.Core.Types ( Haxl/Core/Types.hs, Haxl/Core/Types.o ) [5 of 6] Compiling Haxl.Core.DataCache ( Haxl/Core/DataCache.hs, Haxl/Core/DataCache.o ) [6 of 6] Compiling Bench ( tests/Bench.hs, tests/Bench.o ) Linking tests/Bench-76 ... $ ./tests/Bench-76 500000 Just (Right 0) insert: 0.87s 500000 lookup: 0.24s $ ./tests/Bench-76 500000 Just (Right 0) insert: 0.87s 500000 lookup: 0.26s $ ghc-7.8.2 -O2 tests/Bench.hs -main-is Bench -o tests/Bench-78 [1 of 5] Compiling Haxl.Core.StateStore ( Haxl/Core/StateStore.hs, Haxl/Core/StateStore.o ) [2 of 5] Compiling Haxl.Core.Show1 ( Haxl/Core/Show1.hs, Haxl/Core/Show1.o ) [3 of 5] Compiling Haxl.Core.Types ( Haxl/Core/Types.hs, Haxl/Core/Types.o ) [4 of 5] Compiling Haxl.Core.DataCache ( Haxl/Core/DataCache.hs, Haxl/Core/DataCache.o ) [5 of 5] Compiling Bench ( tests/Bench.hs, tests/Bench.o ) Linking tests/Bench-78 ... $ ./tests/Bench-78 500000 Just (Right 0) insert: 1.09s 500000 lookup: 0.44s $ ./tests/Bench-78 500000 Just (Right 0) insert: 1.08s 500000 lookup: 0.44s }}} -- Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/9203> GHC <http://www.haskell.org/ghc/> The Glasgow Haskell Compiler

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[GHC] #9061: Warnings for redundant imports doesn't take name shadowing into account (Regression)
by GHC 23 Jun '14

23 Jun '14

#9061: Warnings for redundant imports doesn't take name shadowing into account (Regression) -------------------------+------------------------------------------------- Reporter: | Owner: bergmark | Status: new Type: bug | Milestone: Priority: | Version: 7.8.2 normal | Operating System: Unknown/Multiple Component: | Type of failure: Incorrect warning at Compiler | compile-time Keywords: | Test Case: Architecture: | Blocking: Unknown/Multiple | Difficulty: | Unknown | Blocked By: | Related Tickets: | -------------------------+------------------------------------------------- Reproduction: {{{ module Log where import Prelude hiding (log) f :: () f = log where log = () }}} Compiling this with -Wall On GHC 7.8.2: {{{ > ghc Log.hs -Wall [1 of 1] Compiling Log ( Log.hs, Log.o ) Log.hs:3:1: Warning: The import of ‘Prelude’ is redundant except perhaps to import instances from ‘Prelude’ To import instances alone, use: import Prelude() }}} The suggestion is incorrect since removing the import statement gives the following warning: {{{ Log.hs:4:15: Warning: This binding for ‘log’ shadows the existing binding imported from ‘Prelude’ at Log.hs:1:8-10 (and originally defined in ‘GHC.Float’) }}} On GHC 7.6.3 the Reproduction does not give any warnings (which is correct). -- Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/9061> GHC <http://www.haskell.org/ghc/> The Glasgow Haskell Compiler

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[GHC] #9128: Possible bug in strictness analyzer when where clause declared NOINLINE
by GHC 23 Jun '14

23 Jun '14

#9128: Possible bug in strictness analyzer when where clause declared NOINLINE -----------------------------------------+--------------------------------- Reporter: aalevy | Owner: Type: bug | Status: new Priority: normal | Milestone: Component: Compiler | Version: 7.8.2 Keywords: strictness bytestring | Operating System: Architecture: Unknown/Multiple | Unknown/Multiple Difficulty: Unknown | Type of failure: Runtime Blocked By: | crash Related Tickets: | Test Case: | Blocking: -----------------------------------------+--------------------------------- I've encountered the following error message using a relatively straight forward library that wraps postgresql-simple in certain edge cases: {{{ *** Exception: Oops! Entered absent arg a_sYDl{v} [lid] bytestring-0.10.4.0:Data.ByteString.Internal.ByteString{tc r5T} }}} This happens on an invocation of a function, `dbSelect` under certain compilation conditions: {{{ dbSelect :: (Model a) => Connection -> DBSelect a -> IO [a] {-# INLINE #-} dbSelect conn dbs = map lookupRow <$> query_ conn q where {-# NOINLINE #-} q = renderDBSelect dbs }}} A DBSelect is just a data-structure with different `Query` (wrapper around strict bytestring) fields for clauses in a SQL select query. `renderDBSelect` generates a single `Query` value from the DBSelect (by way of contructing a Blaze.Builder as an intermediate step). When compiled with no optimizations, this works fine, no issues. With -O1, I get the error above. The errors goes away, if I compile with -fno- strictness or remove the NOINLINE *or* INLINE pragmas. We've worked around this for now in the library by removgin the NOINLINE pragmas, but tracking this down it seems like the strictness analyzer might be falsly assuming `q` is never actually evaluated. For reference, this is a commit that still exhibits the bug: https://github.com/alevy/postgresql- orm/tree/93075d56ae5ffeb8f80ecc8c01436713c2656a6b I've also attached a small test application that excercises the bug. Because of how the library sets up a scratch database, the test application requires postgres and pg_ctl to be available in the path. -- Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/9128> GHC <http://www.haskell.org/ghc/> The Glasgow Haskell Compiler

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[GHC] #9096: GADT definition not accepted in prefix notation
by GHC 23 Jun '14

23 Jun '14

#9096: GADT definition not accepted in prefix notation ------------------------------------+------------------------------------- Reporter: goldfire | Owner: Type: bug | Status: new Priority: normal | Milestone: Component: Compiler | Version: 7.8.2 Keywords: | Operating System: Unknown/Multiple Architecture: Unknown/Multiple | Type of failure: None/Unknown Difficulty: Unknown | Test Case: Blocked By: | Blocking: Related Tickets: | ------------------------------------+------------------------------------- Brian Nguyen writes on haskell-cafe: The following does not work: {{{ data Foo a where {Foo :: (->) a (Foo a)} }}} -- Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/9096> GHC <http://www.haskell.org/ghc/> The Glasgow Haskell Compiler

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[GHC] #9115: The kind of (=>)
by GHC 23 Jun '14

23 Jun '14

#9115: The kind of (=>) ------------------------------------+------------------------------------- Reporter: kosmikus | Owner: Type: feature request | Status: new Priority: low | Milestone: Component: Compiler | Version: 7.8.2 Keywords: | Operating System: Unknown/Multiple Architecture: Unknown/Multiple | Type of failure: None/Unknown Difficulty: Unknown | Test Case: Blocked By: | Blocking: Related Tickets: | ------------------------------------+------------------------------------- This is mainly a request for clarification, and not very important. Is there any good (theoretical, implementation, practical, ...) reason why (with `ConstraintKinds`) enabled, the `=>` symbol on the type-level is still treated as a built-in syntactic construct rather than a type-level operator with {{{ GHCi> :kind (=>) (=>) :: Constraint -> * -> * }}} Note that I'm not actually proposing to make it re-definable, but to treat it similarly to the `(->)` type operator. -- Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/9115> GHC <http://www.haskell.org/ghc/> The Glasgow Haskell Compiler

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Re: [GHC] #6018: Injective type families
by GHC 22 Jun '14

22 Jun '14

#6018: Injective type families -------------------------------+------------------------------------------- Reporter: lunaris | Owner: simonpj Type: feature | Status: new request | Milestone: 7.10.1 Priority: normal | Version: 7.4.1 Component: Compiler | Keywords: TypeFamilies, Injective Resolution: | Architecture: Unknown/Multiple Operating System: | Difficulty: Unknown Unknown/Multiple | Blocked By: Type of failure: | Related Tickets: #4259 None/Unknown | Test Case: | Blocking: | -------------------------------+------------------------------------------- Changes (by ekmett): * cc: ekmett@… (added) -- Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/6018#comment:31> GHC <http://www.haskell.org/ghc/> The Glasgow Haskell Compiler

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[GHC] #8146: Library package cannot be found
by GHC 20 Jun '14

20 Jun '14

#8146: Library package cannot be found --------------------------------+------------------------------------------ Reporter: conradwt | Owner: Type: bug | Status: new Priority: normal | Milestone: Component: Compiler | Version: 7.6.3 Keywords: | Operating System: Unknown/Multiple Architecture: | Type of failure: Installing GHC failed Unknown/Multiple | Test Case: Difficulty: Unknown | Blocking: Blocked By: | Related Tickets: | --------------------------------+------------------------------------------ {{{ ./sync-all get warning: libffi-tarballs already present; omitting == libffi-tarballs: running git config --local core.ignorecase true warning: utils/hsc2hs already present; omitting == utils/hsc2hs: running git config --local core.ignorecase true warning: utils/haddock already present; omitting == utils/haddock: running git config --local core.ignorecase true == running git clone https://github.com/ghc/packages/array.git libraries/array Cloning into 'libraries/array'... fatal: repository 'https://github.com/ghc/packages/array.git/' not found git failed: 32768 at ./sync-all line 119. == Checking for old haddock repo == Checking for old binary repo == Checking for old mtl repo == Checking for old Cabal repo == Checking for old time from tar ball }}} -- Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/8146> GHC <http://www.haskell.org/ghc/> The Glasgow Haskell Compiler

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