- ghc-tickets - Haskell.org

[GHC] #11351: Scoped type variables in pattern synonyms
by GHC 18 Jan '16

18 Jan '16

#11351: Scoped type variables in pattern synonyms -------------------------------------+------------------------------------- Reporter: Iceland_jack | Owner: Type: feature | Status: new request | Priority: normal | Milestone: Component: Compiler | Version: 8.1 (Type checker) | Keywords: | Operating System: Linux Architecture: | Type of failure: GHC rejects Unknown/Multiple | valid program Test Case: | Blocked By: Blocking: | Related Tickets: Differential Rev(s): | Wiki Page: -------------------------------------+------------------------------------- Unsure of pattern synonym scoping rules. I want to be able to refer to a type in the signature (assuming `symbol` from #11349): {{{#!hs symbol :: forall s. KnownSymbol s => String symbol = symbolVal @s Proxy -- Not in scope: type variable ‘s’ -- Not in scope: type variable ‘s’ pattern Symbol :: forall s. KnownSymbol s => String pattern Symbol <- ((== symbol @s) -> True) where Symbol = symbol @s }}} Without `TypeApplications`: {{{#!hs -- • Could not deduce (KnownSymbol n0) -- arising from a use of ‘symbolVal’ -- from the context: KnownSymbol s -- bound by the type signature for pattern synonym ‘Symbol’: -- String pattern Symbol :: forall s. KnownSymbol s => String pattern Symbol <- ((== symbolVal (Proxy :: Proxy s)) -> True) }}} but it (GHCi, version 8.1.20160102) says the type variable `s` is not in scope. The desired outcome would be something like (this touches on ticket #11350): {{{#!hs >>> Symbol @"blessed duck" "blessed duck" isDuck :: String -> Bool isDuck (Symbol @"duck") = True isDuck _ = False }}} With a nudge and a wink to #9671. -- Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/11351> GHC <http://www.haskell.org/ghc/> The Glasgow Haskell Compiler

1 6

[GHC] #11331: panic! TEST=tc198: lookupVers2 GHC.Stack.Types CallStack
by GHC 18 Jan '16

18 Jan '16

#11331: panic! TEST=tc198: lookupVers2 GHC.Stack.Types CallStack -------------------------------------+------------------------------------- Reporter: thomie | Owner: Type: bug | Status: new Priority: highest | Milestone: 8.0.1 Component: Compiler | Version: 7.11 Keywords: | Operating System: Unknown/Multiple Architecture: | Type of failure: None/Unknown Unknown/Multiple | Test Case: | Blocked By: Blocking: | Related Tickets: Differential Rev(s): | Wiki Page: -------------------------------------+------------------------------------- {{{ $ ghc-head --info | grep Project [("Project name","The Glorious Glasgow Haskell Compilation System") ,("Project version","8.1.20151231") ,("Project Git commit id","8afeaad919dc67643b4eff14efafb48b59039b2b") }}} {{{ $ make slowtest TEST=tc198 TEST_HC=ghc-head VERBOSE=2 =====> tc198(normal) 1 of 1 [0, 0, 0] =====> tc198(hpc) 1 of 1 [0, 0, 0] Compile failed (status 256) errors were: ghc: panic! (the 'impossible' happened) (GHC version 8.1.20151231 for x86_64-unknown-linux): lookupVers2 GHC.Stack.Types CallStack Please report this as a GHC bug: http://www.haskell.org/ghc/reportabug *** unexpected failure for tc198(hpc) =====> tc198(optasm) 1 of 1 [0, 1, 0] Compile failed (status 256) errors were: ghc: panic! (the 'impossible' happened) (GHC version 8.1.20151231 for x86_64-unknown-linux): lookupVers2 GHC.Stack.Types CallStack Please report this as a GHC bug: http://www.haskell.org/ghc/reportabug *** unexpected failure for tc198(optasm) Unexpected results from: TEST="tc198" }}} Test was added in 2005. Seems like a release blocker. -- Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/11331> GHC <http://www.haskell.org/ghc/> The Glasgow Haskell Compiler

1 15

Re: [GHC] #5063: unix package has untracked dependency on libbsd
by GHC 18 Jan '16

18 Jan '16

#5063: unix package has untracked dependency on libbsd -------------------------------------+------------------------------------- Reporter: duncan | Owner: trommler Type: bug | Status: upstream Priority: low | Milestone: 8.2.1 Component: Core Libraries | Version: 7.0.3 Resolution: | Keywords: Operating System: Unknown/Multiple | Architecture: | Unknown/Multiple Type of failure: Other | Test Case: Blocked By: | Blocking: Related Tickets: | Differential Rev(s): Wiki Page: | -------------------------------------+------------------------------------- Changes (by bgamari): * milestone: 8.0.1 => 8.2.1 Comment: What is the status of this? It seems like there have been no patches submitted upstream to resolve this. Punting to 8.2.1 unless informed otherwise. -- Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/5063#comment:15> GHC <http://www.haskell.org/ghc/> The Glasgow Haskell Compiler

1 0

[GHC] #11408: Delicate solve order
by GHC 18 Jan '16

18 Jan '16

#11408: Delicate solve order -------------------------------------+------------------------------------- Reporter: simonpj | Owner: Type: bug | Status: new Priority: normal | Milestone: Component: Compiler | Version: 7.10.3 Keywords: | Operating System: Unknown/Multiple Architecture: | Type of failure: None/Unknown Unknown/Multiple | Test Case: | Blocked By: Blocking: | Related Tickets: Differential Rev(s): | Wiki Page: -------------------------------------+------------------------------------- Should we successfully infer a type for `f`: {{{ f x = [h x, [x]] }}} assuming `h :: forall b. F b -> b`? Assuming `(x::alpha)` and we instantiate `h` at `beta`, we get the constraints {{{ (1) beta ~ [alpha] from the list [h x, [x]] (2) alpha ~ F beta from the call of h }}} Now if we happen to unify the constraint (1) first, `beta := [alpha`], then we successfully infer {{{ f :: forall a. (a ~ F [a]) => a -> [[a]] }}} But if we unify the constraint (2) first, `alpha := F beta`, we get {{{ f :: forall b. (b ~ [F b]) => F b -> [[F b]] }}} which is ambiguous. Eeek! This actually shows up in type inference for `indexed- types/should_compile/IndTypesPerfMerge`, where the function `merge` has (a slightly more complicated form of) this delicately-balanced situation. But see `Note [Orientation of equalities with fmvs]` in `TcFlatten` for why we don't defer solving (2). -- Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/11408> GHC <http://www.haskell.org/ghc/> The Glasgow Haskell Compiler

1 5

[GHC] #11422: outofmem RTS testcase fails on Windows
by GHC 18 Jan '16

18 Jan '16

#11422: outofmem RTS testcase fails on Windows ----------------------------------------+--------------------------------- Reporter: Phyx- | Owner: Phyx- Type: bug | Status: new Priority: normal | Milestone: 8.0.1 Component: Compiler | Version: 7.10.3 Keywords: | Operating System: Windows Architecture: Unknown/Multiple | Type of failure: None/Unknown Test Case: outpfmem | Blocked By: Blocking: | Related Tickets: #11300 Differential Rev(s): Phab:D1753 | Wiki Page: ----------------------------------------+--------------------------------- The `outofmem` test case fails on Windows `x86` and `x86_64` with the wrong exit code. Expected `251` but gotten `1`. -- Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/11422> GHC <http://www.haskell.org/ghc/> The Glasgow Haskell Compiler

1 4

[GHC] #11367: [Regression] Pattern synonyms
by GHC 18 Jan '16

18 Jan '16

#11367: [Regression] Pattern synonyms -------------------------------------+------------------------------------- Reporter: Iceland_jack | Owner: Type: bug | Status: new Priority: normal | Milestone: Component: Compiler | Version: 8.1 Keywords: | Operating System: Unknown/Multiple Architecture: | Type of failure: GHC rejects Unknown/Multiple | valid program Test Case: | Blocked By: Blocking: | Related Tickets: Differential Rev(s): | Wiki Page: -------------------------------------+------------------------------------- Regression. This worked in 7.10.2: {{{#!hs {-# LANGUAGE PatternSynonyms, ViewPatterns #-} pattern A :: Int -> String pattern A n <- (read -> n) where A 0 = "hi" A 1 = "bye" }}} Removing the final clause works in GHC head but given the same code it claims the clause is empty: {{{ % ghci -ignore-dot-ghci /tmp/tmp.t0h0pMgwWb.hs GHCi, version 8.1.20160105: http://www.haskell.org/ghc/ :? for help [1 of 1] Compiling Main ( /tmp/tmp.t0h0pMgwWb.hs, interpreted ) /tmp/tmp.t0h0pMgwWb.hs:4:9: error: pattern synonym 'where' clause cannot be empty In the pattern synonym declaration for: A Failed, modules loaded: none. Prelude> }}} The where clause is certainly not empty — ironically seems to be caused by my very own #10426 ([https://phabricator.haskell.org/D1665 D1665]) :--) hoist by my own ticket as we say: {{{#!hs ; when (length matches /= 1) (wrongNumberErr loc) }}} Personally a trailing `where` is quite alright and handy when quickly checking if a declaration is otherwise OK. It works for data/newtype declarations as well as type classes. A workaround is to pattern match in other ways: {{{#!hs pattern A n <- ... where A = \case 0 -> "hi" 1 -> "bye" }}} -- Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/11367> GHC <http://www.haskell.org/ghc/> The Glasgow Haskell Compiler

1 19

[GHC] #11252: :kind command hides the explicit kind
by GHC 18 Jan '16

18 Jan '16

#11252: :kind command hides the explicit kind ----------------------------------------+-------------------------- Reporter: Iceland_jack | Owner: Type: feature request | Status: new Priority: normal | Milestone: Component: GHCi | Version: 7.11 Keywords: TypeInType | Operating System: Linux Architecture: Unknown/Multiple | Type of failure: Other Test Case: | Blocked By: Blocking: | Related Tickets: Differential Rev(s): | Wiki Page: ----------------------------------------+-------------------------- {{{#!hs -- /tmp/test.hs {-# LANGUAGE TypeInType #-} data Proxy1 k (a :: k) = P1 data Proxy2 (a :: k) = P2 }}} if I load the following into ghci (head) the `:kind` command gives the same result {{{#!haskell % ghci -ignore-dot-ghci /tmp/test.hs GHCi, version 7.11.20151216: http://www.haskell.org/ghc/ :? for help [1 of 1] Compiling Main ( test.hs, interpreted ) Ok, modules loaded: Main. *Main> :kind Proxy1 :kind Proxy1 Proxy1 :: k -> * *Main> :kind Proxy2 :kind Proxy2 Proxy2 :: k -> * }}} -- Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/11252> GHC <http://www.haskell.org/ghc/> The Glasgow Haskell Compiler

1 7

[GHC] #11093: T9579 fails on OS X
by GHC 18 Jan '16

18 Jan '16

#11093: T9579 fails on OS X -------------------------------------+------------------------------------- Reporter: bgamari | Owner: Type: bug | Status: new Priority: normal | Milestone: 8.0.1 Component: Compiler | Version: 7.10.2 Keywords: | Operating System: Unknown/Multiple Architecture: | Type of failure: None/Unknown Unknown/Multiple | Test Case: | Blocked By: Blocking: | Related Tickets: Differential Rev(s): | Wiki Page: -------------------------------------+------------------------------------- As pointed out in ticket:9579#comment:19 the testcase T9579 fails on OS X, {{{ Actual stdout output differs from expected: --- ./T9579_outofheap_rtsall.stdout.normalised 2015-06-16 14:06:15.000000000 -0400 +++ ./T9579_outofheap_rtsall.run.stdout.normalised 2015-06-16 14:06:15.000000000 -0400 @@ -1,4 +1,4 @@ T9579_outofheap_rtsall: Heap exhausted; -T9579_outofheap_rtsall: Current maximum heap size is NUM bytes (1 MB). +T9579_outofheap_rtsall: Current maximum heap size is 1048576 bytes (1 MB). T9579_outofheap_rtsall: Use `+RTS -M<size>' to increase it. 251 \ No newline at end of file *** unexpected failure for T9579_outofheap_rtsall(normal) }}} The issue appears to be a difference in `sed`'s behavior on OS X. The number in the error message is supposed to be replaced by `NUM` with `sed -e 's/[0-9]* bytes/NUM bytes/g'`. Perhaps someone with access to an OS X box could shed some light on this? -- Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/11093> GHC <http://www.haskell.org/ghc/> The Glasgow Haskell Compiler

1 3

[GHC] #11300: outofmem RTS testcase fails on ARM
by GHC 18 Jan '16

18 Jan '16

#11300: outofmem RTS testcase fails on ARM --------------------------------+---------------------------------- Reporter: bgamari | Owner: bgamari Type: bug | Status: new Priority: normal | Milestone: 8.0.1 Component: Compiler | Version: 7.10.3 Keywords: | Operating System: Linux Architecture: arm | Type of failure: Runtime crash Test Case: | Blocked By: Blocking: | Related Tickets: Differential Rev(s): | Wiki Page: --------------------------------+---------------------------------- The `outofmem` RTS testcase fails on ARM, {{{ =====> outofmem(normal) 1 of 1 [0, 0, 0] cd . && $MAKE -s --no-print-directory outofmem </dev/null > outofmem.run.stdout 2> outofmem.run.stderr Actual stdout output differs from expected: --- ./outofmem.stdout.normalised 2015-12-27 17:21:08.718240403 +0100 +++ ./outofmem.run.stdout.normalised 2015-12-27 17:21:08.718240403 +0100 @@ -1 +1 @@ -exit(251) \ No newline at end of file +exit(1) \ No newline at end of file *** unexpected failure for outofmem(normal) }}} In particular, {{{ $ make outofmem make[1]: Entering directory '/mnt/ext/exp/ghc/testsuite/tests/rts' '/mnt/ext/exp/ghc/inplace/test spaces/ghc-stage2' -fforce-recomp -dcore- lint -dcmm-lint -dno-debug-output -no-user-package-db -rtsopts -fno-warn- tabs -fno-warn-missed-specialisations -v0 --make -fforce-recomp outofmem.hs -o outofmem make[1]: Leaving directory '/mnt/ext/exp/ghc/testsuite/tests/rts' outofmem: out of memory (requested 1074790400 bytes) exit(1) }}} -- Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/11300> GHC <http://www.haskell.org/ghc/> The Glasgow Haskell Compiler

1 14

[GHC] #11430: ApiAnnotations: work SourceText in for all integer literals
by GHC 18 Jan '16

18 Jan '16

#11430: ApiAnnotations: work SourceText in for all integer literals -------------------------------------+------------------------------------- Reporter: alanz | Owner: alanz Type: bug | Status: new Priority: normal | Milestone: 8.0.1 Component: Compiler | Version: 8.1 Keywords: | Operating System: Unknown/Multiple Architecture: | Type of failure: Incorrect API Unknown/Multiple | annotation Test Case: | Blocked By: Blocking: | Related Tickets: Differential Rev(s): | Wiki Page: -------------------------------------+------------------------------------- Certain syntactic elements have integers in them, such as fixity specifications, SPECIALISE pragmas and so on. The lexer will accept mult-radix literals, with arbitrary leading zeros in these. Bring in a SourceText field to each affected AST element to capture the original literal text for use with API Annotations. -- Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/11430> GHC <http://www.haskell.org/ghc/> The Glasgow Haskell Compiler

1 5