October 2018 - ghc-tickets

[GHC] #15124: Improve block layout for the NCG
by GHC 17 Nov '18

17 Nov '18

#15124: Improve block layout for the NCG -------------------------------------+------------------------------------- Reporter: AndreasK | Owner: (none) Type: task | Status: new Priority: normal | Milestone: 8.6.1 Component: Compiler | Version: 8.2.2 (NCG) | Keywords: CodeGen | Operating System: Unknown/Multiple Architecture: | Type of failure: None/Unknown Unknown/Multiple | Test Case: | Blocked By: Blocking: | Related Tickets: Differential Rev(s): | Wiki Page: -------------------------------------+------------------------------------- The current codegen tries to place two blocks A and B next to each other if they are "close". = Drawbacks of the current algorithm Blocks are only considered close if one jumps to the other via a unconditional jump instructions. This is a fast and reasonable approximation. But we might be able to do better. == Calls are not considered even if they always return to the same block. For example it's clear that if foo == bar we jump to C here: {{{ A: movq $block_C_info,-16(%rbp) cmp foo,bar jne D B: jmp *(%rbx) #Returns to C ... .align 8 .infotable block_C_info: C: doThings }}} == Conditional jumps are never considered. The following block either jumps directly to c3mQ or returns there from a call. Yet that is completely ignored by the current algorithm. {{{ _c3mG: movq $block_c3mQ_info,-8(%rbp) ... jne _c3mQ jmp *(%rbx) #returns to c3mQ }}} == Likelyhood of branches is not considered. We track information about branches which are rarely taken at the cmm level. However this information is currently lost during the Cmm -> Asm transformation which happens before we do code layout. This means for Cmm code where one branch is never executed the branch that's never executed might be the only one considered relevant. This happens for example for this stack check: {{{ if ((Sp + -40) >= SpLim) (likely: True) goto c5PS; else goto c5Q3; }}} = Potential gains If nothing else this would allow some Cmm optimizations which are made useless by the current code layout algorithm. I have hit cases where the block layout algorithm turned optimizations into pessimizations of 2-5% by pulling obvious loops apart. Given that the scenario that leads to loops being pulled apart doesn't seem that unlikely I assume some loops are also pulled apart like this in HEAD. Cleaning this up ideally would also make it possible to move blocks which are not part of loops out of them. -- Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/15124> GHC <http://www.haskell.org/ghc/> The Glasgow Haskell Compiler

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[GHC] #10675: GHC does not check the functional dependency consistency condition correctly
by GHC 16 Nov '18

16 Nov '18

#10675: GHC does not check the functional dependency consistency condition correctly -------------------------------------+------------------------------------- Reporter: simonpj | Owner: Type: bug | Status: new Priority: normal | Milestone: Component: Compiler | Version: 7.10.1 Keywords: | Operating System: Unknown/Multiple Architecture: | Type of failure: None/Unknown Unknown/Multiple | Test Case: | Blocked By: Blocking: | Related Tickets: Differential Revisions: | -------------------------------------+------------------------------------- Consider {{{ {-# LANGUAGE MultiParamTypeClasses, FunctionalDependencies, FlexibleInstances, UndecidableInstances, ScopedTypeVariables #-} class C a b | a -> b where op :: a -> b instance C [x] [x] instance {-# OVERLAPS #-} C x y => C [x] [Maybe y] f x = op [x] }}} Should these two instance declarations be accepted? They are simply ''inconsistent'' in the sense of Definition 6 of the [http://research.microsoft.com/en-us/um/people/simonpj/papers/fd- chr/jfp06.pdf FDs through CHRs paper]. Sadly GHC does not currently reject these as inconsistent. As a result it'll use ''both'' instance for improvement. In the definition of `f` for example we get {{{ C [alpha] beta }}} where `x:alpha` and the result type of `f` is `beta`. By using both instances for improvement we get {{{ C [Maybe gamma] [Maybe gamma] }}} Is that what we want? The two instances don't ''contradict'' each other, but neither do they agree as all published work on FDs says they should! Examples in the testsuite that exploit this loophole are {{{ ghci/scripts ghci047 polykinds T9106 typecheck/should_compile FD4 typecheck/should_compile T7875 }}} I'm not sure what the right thing here is. -- Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/10675> GHC <http://www.haskell.org/ghc/> The Glasgow Haskell Compiler

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[GHC] #14742: Unboxed sums can treat Int#s as Word#s
by GHC 16 Nov '18

16 Nov '18

#14742: Unboxed sums can treat Int#s as Word#s -------------------------------------+------------------------------------- Reporter: duog | Owner: (none) Type: bug | Status: new Priority: normal | Milestone: Component: Compiler | Version: 8.2.2 Keywords: UnboxedSums | Operating System: Unknown/Multiple Architecture: | Type of failure: None/Unknown Unknown/Multiple | Test Case: | Blocked By: Blocking: | Related Tickets: Differential Rev(s): | Wiki Page: -------------------------------------+------------------------------------- Consider the following module: {{{ {-# language MagicHash, UnboxedSums #-} {-# options_ghc -ddump-stg -dppr-debug -fprint-explicit-kinds -ddump-to- file #-} module Bug where import GHC.Prim import GHC.Types mkUnboxedSum :: () -> (# Float# | Int# #) mkUnboxedSum _ = (# | 9# #) {-# noinline mkUnboxedSum #-} foo :: Int foo = case mkUnboxedSum () of (# | i# #) -> I# i# (# f# | #) -> 8 }}} The full .dump-stg is attached. An abbreviation of the case statement in foo is: {{{ case (...) of (...) { ghc-prim:GHC.Prim.(#,,#){(w) d 89} ((us_g1h9{v} [lid] :: ghc- prim:GHC.Types.Any{(w) tc 35K} (ghc- prim:GHC.Prim.TYPE{(w) tc 32Q} 'ghc-prim:GHC.Types.WordRep{(w) d 63J})) :: ghc- prim:GHC.Types.Any{(w) tc 35K} (ghc- prim:GHC.Prim.TYPE{(w) tc 32Q} 'ghc- prim:GHC.Types.WordRep{(w) d 63J})) ((us_g1ha{v} [lid] :: ghc- prim:GHC.Types.Any{(w) tc 35K} (ghc- prim:GHC.Prim.TYPE{(w) tc 32Q} 'ghc-prim:GHC.Types.WordRep{(w) d 63J})) :: ghc- prim:GHC.Types.Any{(w) tc 35K} (ghc- prim:GHC.Prim.TYPE{(w) tc 32Q} 'ghc- prim:GHC.Types.WordRep{(w) d 63J})) ((us_g1hb{v} [lid] :: ghc- prim:GHC.Types.Any{(w) tc 35K} (ghc- prim:GHC.Prim.TYPE{(w) tc 32Q} 'ghc-prim:GHC.Types.FloatRep{(w) d 63V})) :: ghc- prim:GHC.Types.Any{(w) tc 35K} (ghc- prim:GHC.Prim.TYPE{(w) tc 32Q} 'ghc- prim:GHC.Types.FloatRep{(w) d 63V})) -> case (us_g1h9{v} [lid] :: ghc-prim:GHC.Types.Any{(w) tc 35K} (ghc-prim:GHC.Prim.TYPE{(w) tc 32Q} 'ghc- prim:GHC.Types.WordRep{(w) d 63J})) :: Prim IntRep of ((tag_g1hc{v} [lid] :: ghc-prim:GHC.Prim.Int#{(w) tc 3s}) :: ghc-prim:GHC.Prim.Int#{(w) tc 3s}) { __DEFAULT -> ghc-prim:GHC.Types.I#{(w) d 6i} [8#]; 2# -> ghc-prim:GHC.Types.I#{(w) d 6i} [(us_g1ha{v} [lid] :: ghc-prim:GHC.Types.Any{(w) tc 35K} (ghc-prim:GHC.Prim.TYPE{(w) tc 32Q} 'ghc-prim:GHC.Types.WordRep{(w) d 63J}))]; }; }}} Note that: * `us_g1h9 :: Any (TYPE WordRep)`; * `us_g1ha :: Any (Type WordRep)`; * `tag_g1hc :: Int#`; * The `2#` alternative passes `us_g1ha` to an `I#` constructor. This seems wrong to me. It comes about because `slotPrimRep . primRepSlot` (in RepType) is not the identity. StgLint found this while I was working on ticket:14541 -- Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/14742> GHC <http://www.haskell.org/ghc/> The Glasgow Haskell Compiler

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[GHC] #14343: bad pretty-printing of types with promoted data types
by GHC 15 Nov '18

15 Nov '18

#14343: bad pretty-printing of types with promoted data types -------------------------------------+------------------------------------- Reporter: lspitzner | Owner: (none) Type: bug | Status: new Priority: normal | Milestone: Component: Compiler | Version: 8.2.1 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: -------------------------------------+------------------------------------- {{{ > :set -XDataKinds > :set -XPolyKinds > data Proxy k = Proxy > _ :: Proxy '[ 'True ] error: Found hole: _ :: Proxy '['True] > _ :: Proxy '['True] error: Invalid type signature: _ :: ... Should be of form <variable> :: <type> }}} Alternatively, this could be attributed to the parser/lexer doing an insufficient job there. -- Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/14343> GHC <http://www.haskell.org/ghc/> The Glasgow Haskell Compiler

1 9

[GHC] #15466: debug validation failures
by GHC 15 Nov '18

15 Nov '18

#15466: debug validation failures --------------------------------------+--------------------------------- Reporter: alpmestan | Owner: (none) Type: bug | Status: new Priority: normal | Milestone: Component: Compiler | Version: 8.5 Keywords: | Operating System: Linux Architecture: x86_64 (amd64) | Type of failure: None/Unknown Test Case: | Blocked By: Blocking: | Related Tickets: Differential Rev(s): | Wiki Page: --------------------------------------+--------------------------------- The most recent completed run of `validate-x86_64-linux-debug` on Circle CI (https://circleci.com/gh/ghc/ghc/7730) shows 13 unexpected failures and 1 unexpected pass. **Summary** {{{ Unexpected passes: concurrent/T13615/T13615.run T13615 [unexpected] (ghci) Unexpected failures: codeGen/should_compile/T9329.run T9329 [exit code non-0] (normal) codeGen/should_run/cgrun018.run cgrun018 [exit code non-0] (normal) codeGen/should_run/cgrun018.run cgrun018 [exit code non-0] (g1) codeGen/should_run/cgrun069.run cgrun069 [exit code non-0] (normal) codeGen/should_run/cgrun069.run cgrun069 [exit code non-0] (g1) codeGen/should_run/T9577.run T9577 [bad stdout] (normal) concurrent/should_run/T3429.run T3429 [bad exit code] (debug_numa) driver/T14075/T14075.run T14075 [bad stderr] (normal) driver/recomp007/recomp007.run recomp007 [bad stderr] (normal) rts/T14702.run T14702 [bad exit code] (threaded1) rts/nursery-chunks1.run nursery-chunks1 [bad stderr] (threaded1) rts/numa001.run numa001 [bad exit code] (debug_numa) ../../libraries/base/tests/T11760.run T11760 [bad exit code] (normal) }}} --- **T9329** {{{ Compile failed (exit code 1) errors were: /tmp/ghc78722_0/ghc_4.hc: In function ‘bar’: /tmp/ghc78722_0/ghc_4.hc:18:12: error: error: ‘c6_info’ undeclared (first use in this function) *Sp = (W_)&c6_info; ^ /tmp/ghc78722_0/ghc_4.hc:18:12: error: note: each undeclared identifier is reported only once for each function it appears in `gcc' failed in phase `C Compiler'. (Exit code: 1) *** unexpected failure for T9329(normal) }}} **cgrun018** {{{ Compile failed (exit code 1) errors were: [1 of 1] Compiling Main ( cgrun018.hs, cgrun018.o ) ghc-stage2: panic! (the 'impossible' happened) (GHC version 8.7.20180731 for x86_64-unknown-linux): pprStatics: float F32 F32 F32 F32 F32 F32 F32 F32 F32 F32 F32 Call stack: CallStack (from HasCallStack): callStackDoc, called at compiler/utils/Outputable.hs:1164:37 in ghc:Outputable pprPanic, called at compiler/cmm/PprC.hs:521:5 in ghc:PprC Please report this as a GHC bug: http://www.haskell.org/ghc/reportabug *** unexpected failure for cgrun018(normal) --- Compile failed (exit code 1) errors were: [1 of 1] Compiling Main ( cgrun018.hs, cgrun018.o ) ghc-stage2: panic! (the 'impossible' happened) (GHC version 8.7.20180731 for x86_64-unknown-linux): pprStatics: float F32 F32 F32 F32 F32 F32 F32 F32 F32 F32 F32 Call stack: CallStack (from HasCallStack): callStackDoc, called at compiler/utils/Outputable.hs:1164:37 in ghc:Outputable pprPanic, called at compiler/cmm/PprC.hs:521:5 in ghc:PprC Please report this as a GHC bug: http://www.haskell.org/ghc/reportabug *** unexpected failure for cgrun018(g1) }}} **cgrun069** {{{ Compile failed (exit code 1) errors were: /tmp/ghc83995_0/ghc_4.hc:5:12: error: error: conflicting types for ‘memsetErr’ const char memsetErr[] = "Memset Error - align: %d size: %d\012"; ^ In file included from /tmp/ghc83995_0/ghc_4.hc:3:0: error: /tmp/ghc83995_0/ghc_4.hc:4:6: error: note: previous declaration of ‘memsetErr’ was here ERW_(memsetErr); ^ /home/ghc/project/includes/Stg.h:242:46: error: note: in definition of macro ‘ERW_’ #define ERW_(X) extern StgWordArray (X) ^ /tmp/ghc83995_0/ghc_4.hc:8:12: error: error: conflicting types for ‘memcpyErr’ const char memcpyErr[] = "Memcpy Error - align: %d size: %d\012"; ^ In file included from /tmp/ghc83995_0/ghc_4.hc:3:0: error: /tmp/ghc83995_0/ghc_4.hc:7:6: error: note: previous declaration of ‘memcpyErr’ was here ERW_(memcpyErr); ^ /home/ghc/project/includes/Stg.h:242:46: error: note: in definition of macro ‘ERW_’ #define ERW_(X) extern StgWordArray (X) ^ /tmp/ghc83995_0/ghc_4.hc:11:12: error: error: conflicting types for ‘memmoveErr’ const char memmoveErr[] = "Memmove Error Occured\012"; ^ In file included from /tmp/ghc83995_0/ghc_4.hc:3:0: error: /tmp/ghc83995_0/ghc_4.hc:10:6: error: note: previous declaration of ‘memmoveErr’ was here ERW_(memmoveErr); ^ /home/ghc/project/includes/Stg.h:242:46: error: note: in definition of macro ‘ERW_’ #define ERW_(X) extern StgWordArray (X) ^ `gcc' failed in phase `C Compiler'. (Exit code: 1) *** unexpected failure for cgrun069(normal) --- Compile failed (exit code 1) errors were: /tmp/ghc84416_0/ghc_4.hc:5:12: error: error: conflicting types for ‘memsetErr’ const char memsetErr[] = "Memset Error - align: %d size: %d\012"; ^ In file included from /tmp/ghc84416_0/ghc_4.hc:3:0: error: /tmp/ghc84416_0/ghc_4.hc:4:6: error: note: previous declaration of ‘memsetErr’ was here ERW_(memsetErr); ^ /home/ghc/project/includes/Stg.h:242:46: error: note: in definition of macro ‘ERW_’ #define ERW_(X) extern StgWordArray (X) ^ /tmp/ghc84416_0/ghc_4.hc:8:12: error: error: conflicting types for ‘memcpyErr’ const char memcpyErr[] = "Memcpy Error - align: %d size: %d\012"; ^ In file included from /tmp/ghc84416_0/ghc_4.hc:3:0: error: /tmp/ghc84416_0/ghc_4.hc:7:6: error: note: previous declaration of ‘memcpyErr’ was here ERW_(memcpyErr); ^ /home/ghc/project/includes/Stg.h:242:46: error: note: in definition of macro ‘ERW_’ #define ERW_(X) extern StgWordArray (X) ^ /tmp/ghc84416_0/ghc_4.hc:11:12: error: error: conflicting types for ‘memmoveErr’ const char memmoveErr[] = "Memmove Error Occured\012"; ^ In file included from /tmp/ghc84416_0/ghc_4.hc:3:0: error: /tmp/ghc84416_0/ghc_4.hc:10:6: error: note: previous declaration of ‘memmoveErr’ was here ERW_(memmoveErr); ^ /home/ghc/project/includes/Stg.h:242:46: error: note: in definition of macro ‘ERW_’ #define ERW_(X) extern StgWordArray (X) ^ `gcc' failed in phase `C Compiler'. (Exit code: 1) *** unexpected failure for cgrun069(g1) }}} **T9577** {{{ --- ./codeGen/should_run/T9577.run/T9577.stdout.normalised 2018-08-02 03:38:39.932680724 +0000 +++ ./codeGen/should_run/T9577.run/T9577.run.stdout.normalised 2018-08-02 03:38:39.932680724 +0000 @@ -1 +1 @@ -True +False *** unexpected failure for T9577(normal) }}} **T3429** {{{ Wrong exit code for T3429(debug_numa)(expected 0 , actual 1 ) Stderr ( T3429 ): T3429: unknown RTS option: -N2 T3429: T3429: Usage: <prog> <args> [+RTS <rtsopts> | -RTS <args>] ... --RTS <args> T3429: T3429: +RTS Indicates run time system options follow T3429: -RTS Indicates program arguments follow T3429: --RTS Indicates that ALL subsequent arguments will be given to the T3429: program (including any of these RTS flags) T3429: T3429: The following run time system options are available: T3429: T3429: -? Prints this message and exits; the program is not executed T3429: --info Print information about the RTS used by this program T3429: T3429: -K<size> Sets the maximum stack size (default: 80% of the heap) T3429: Egs: -K32k -K512k -K8M T3429: -ki<size> Sets the initial thread stack size (default 1k) Egs: -ki4k -ki2m T3429: -kc<size> Sets the stack chunk size (default 32k) T3429: -kb<size> Sets the stack chunk buffer size (default 1k) T3429: T3429: -A<size> Sets the minimum allocation area size (default 1m) Egs: -A20m -A10k T3429: -AL<size> Sets the amount of large-object memory that can be allocated T3429: before a GC is triggered (default: the value of -A) T3429: -n<size> Allocation area chunk size (0 = disabled, default: 0) T3429: -O<size> Sets the minimum size of the old generation (default 1M) T3429: -M<size> Sets the maximum heap size (default unlimited) Egs: -M256k -M1G T3429: -H<size> Sets the minimum heap size (default 0M) Egs: -H24m -H1G T3429: -xb<addr> Sets the address from which a suitable start for the heap memory T3429: will be searched from. This is useful if the default address T3429: clashes with some third-party library. T3429: -m<n> Minimum % of heap which must be available (default 3%) T3429: -G<n> Number of generations (default: 2) T3429: -c<n> Use in-place compaction instead of copying in the oldest generation T3429: when live data is at least <n>% of the maximum heap size set with T3429: -M (default: 30%) T3429: -c Use in-place compaction for all oldest generation collections T3429: (the default is to use copying) T3429: -w Use mark-region for the oldest generation (experimental) T3429: -I<sec> Perform full GC after <sec> idle time (default: 0.3, 0 == off) T3429: T3429: -T Collect GC statistics (useful for in-program statistics access) T3429: -t[<file>] One-line GC statistics (if <file> omitted, uses stderr) T3429: -s[<file>] Summary GC statistics (if <file> omitted, uses stderr) T3429: -S[<file>] Detailed GC statistics (if <file> omitted, uses stderr) T3429: T3429: T3429: -Z Don't squeeze out update frames on stack overflow T3429: -B Sound the bell at the start of each garbage collection T3429: T3429: -hT Produce a heap profile grouped by closure type T3429: -l[flags] Log events in binary format to the file <program>.eventlog T3429: -v[flags] Log events to stderr T3429: where [flags] can contain: T3429: s scheduler events T3429: g GC and heap events T3429: p par spark events (sampled) T3429: f par spark events (full detail) T3429: u user events (emitted from Haskell code) T3429: a all event classes above T3429: t add time stamps (only useful with -v) T3429: -x disable an event class, for any flag above T3429: the initial enabled event classes are 'sgpu' T3429: T3429: -h Heap residency profile (output file <program>.hp) T3429: -i<sec> Time between heap profile samples (seconds, default: 0.1) T3429: T3429: -r<file> Produce ticky-ticky statistics (with -rstderr for stderr) T3429: T3429: -C<secs> Context-switch interval in seconds. T3429: 0 or no argument means switch as often as possible. T3429: Default: 0.02 sec. T3429: -V<secs> Master tick interval in seconds (0 == disable timer). T3429: This sets the resolution for -C and the heap profile timer -i, T3429: and is the frequency of time profile samples. T3429: Default: 0.01 sec. T3429: T3429: -Ds DEBUG: scheduler T3429: -Di DEBUG: interpreter T3429: -Dw DEBUG: weak T3429: -DG DEBUG: gccafs T3429: -Dg DEBUG: gc T3429: -Db DEBUG: block T3429: -DS DEBUG: sanity T3429: -Dt DEBUG: stable T3429: -Dp DEBUG: prof T3429: -Da DEBUG: apply T3429: -Dl DEBUG: linker T3429: -Dm DEBUG: stm T3429: -Dz DEBUG: stack squeezing T3429: -Dc DEBUG: program coverage T3429: -Dr DEBUG: sparks T3429: -DC DEBUG: compact T3429: T3429: NOTE: DEBUG events are sent to stderr by default; add -l to create a T3429: binary event log file instead. T3429: T3429: --install-signal-handlers=<yes|no> T3429: Install signal handlers (default: yes) T3429: -e<n> Maximum number of outstanding local sparks (default: 4096) T3429: -xm Base address to mmap memory in the GHCi linker T3429: (hex; must be <80000000) T3429: -xq The allocation limit given to a thread after it receives T3429: an AllocationLimitExceeded exception. (default: 100k) T3429: T3429: -Mgrace=<n> T3429: The amount of allocation after the program receives a T3429: HeapOverflow exception before the exception is thrown again, if T3429: the program is still exceeding the heap limit. T3429: T3429: RTS options may also be specified using the GHCRTS environment variable. T3429: T3429: Other RTS options may be available for programs compiled a different way. T3429: The GHC User's Guide has full details. T3429: *** unexpected failure for T3429(debug_numa) }}} **T13615** {{{ *** unexpected pass for T13615(ghci) }}} **T14075** {{{ Actual stderr output differs from expected: --- ./driver/T14075/T14075.run/T14075.stderr.normalised 2018-08-02 03:40:01.063504007 +0000 +++ ./driver/T14075/T14075.run/T14075.run.stderr.normalised 2018-08-02 03:40:01.063504007 +0000 @@ -1,3 +1,4 @@ +ghc: setNumCapabilities: not supported on this platform F.hs:1:1: instance O.O F.F -- Defined at F.hs-boot:6:10 *** unexpected failure for T14075(normal) }}} **recomp007** {{{ Actual stderr output differs from expected: --- /dev/null 2018-08-01 14:11:13.420752000 +0000 +++ ./driver/recomp007/recomp007.run/recomp007.run.stderr.normalised 2018-08-02 03:40:46.313078664 +0000 @@ -0,0 +1,122 @@ +WARNING: file compiler/utils/ListSetOps.hs, line 58 + [] + [Distribution.Backpack, Distribution.Backpack.FullUnitId, + Distribution.Backpack.ModuleShape, + Distribution.Backpack.PreModuleShape, + Distribution.Backpack.ReadyComponent, + Distribution.CabalSpecVersion, Distribution.Compat.Graph, + Distribution.Compat.Semigroup, Distribution.Compiler, + Distribution.License, Distribution.ModuleName, + Distribution.Parsec.Common, Distribution.SPDX.License, + Distribution.SPDX.LicenseExceptionId, + Distribution.SPDX.LicenseExpression, Distribution.SPDX.LicenseId, + Distribution.SPDX.LicenseReference, + Distribution.Simple.BuildTarget, Distribution.Simple.Compiler, + Distribution.Simple.Doctest, Distribution.Simple.Flag, + Distribution.Simple.Haddock, Distribution.Simple.InstallDirs, + Distribution.Simple.PackageIndex, Distribution.Simple.Program.Find, + Distribution.Simple.Program.GHC, Distribution.Simple.Program.Types, + Distribution.Simple.Setup, Distribution.System, + Distribution.Types.AbiDependency, Distribution.Types.AbiHash, + Distribution.Types.Benchmark, + Distribution.Types.BenchmarkInterface, + Distribution.Types.BenchmarkType, Distribution.Types.BuildInfo, + Distribution.Types.BuildType, Distribution.Types.ComponentId, + Distribution.Types.ComponentLocalBuildInfo, + Distribution.Types.ComponentName, + Distribution.Types.ComponentRequestedSpec, + Distribution.Types.CondTree, Distribution.Types.Condition, + Distribution.Types.Dependency, Distribution.Types.ExeDependency, + Distribution.Types.Executable, Distribution.Types.ExecutableScope, + Distribution.Types.ExposedModule, Distribution.Types.ForeignLib, + Distribution.Types.ForeignLibOption, + Distribution.Types.ForeignLibType, + Distribution.Types.GenericPackageDescription, + Distribution.Types.IncludeRenaming, + Distribution.Types.InstalledPackageInfo, + Distribution.Types.LegacyExeDependency, Distribution.Types.Library, + Distribution.Types.LocalBuildInfo, Distribution.Types.Mixin, + Distribution.Types.Module, Distribution.Types.ModuleReexport, + Distribution.Types.ModuleRenaming, + Distribution.Types.MungedPackageId, + Distribution.Types.MungedPackageName, + Distribution.Types.PackageDescription, + Distribution.Types.PackageId, Distribution.Types.PackageName, + Distribution.Types.PkgconfigDependency, + Distribution.Types.PkgconfigName, + Distribution.Types.SetupBuildInfo, Distribution.Types.SourceRepo, + Distribution.Types.TargetInfo, Distribution.Types.TestSuite, + Distribution.Types.TestSuiteInterface, Distribution.Types.TestType, + Distribution.Types.UnitId, Distribution.Types.UnqualComponentName, + Distribution.Types.Version, Distribution.Types.VersionRange, + Distribution.Utils.ShortText, Distribution.Verbosity, + Language.Haskell.Extension, Control.Applicative, Data.Complex, + Data.Functor.Compose, Data.Functor.Const, Data.Functor.Identity, + Data.Functor.Product, Data.Functor.Sum, Data.Monoid, + Data.Semigroup, Data.Semigroup.Internal, Data.Version, Data.Void, + GHC.Exts, GHC.Generics, GHC.IO.Exception, Data.Graph, + Data.IntMap.Internal, Data.IntSet.Internal, Data.Map.Internal, + Data.Sequence.Internal, Data.Set.Internal, Data.Tree, + Text.PrettyPrint.Annotated.HughesPJ, Text.PrettyPrint.HughesPJ, + Data.Text, Data.Text.Lazy] +WARNING: file compiler/utils/ListSetOps.hs, line 58 + [Distribution.Backpack, Distribution.Backpack.FullUnitId, + Distribution.Backpack.ModuleShape, + Distribution.Backpack.PreModuleShape, + Distribution.Backpack.ReadyComponent, + Distribution.CabalSpecVersion, Distribution.Compat.Graph, + Distribution.Compat.Semigroup, Distribution.Compiler, + Distribution.License, Distribution.ModuleName, + Distribution.Parsec.Common, Distribution.SPDX.License, + Distribution.SPDX.LicenseExceptionId, + Distribution.SPDX.LicenseExpression, Distribution.SPDX.LicenseId, + Distribution.SPDX.LicenseReference, + Distribution.Simple.BuildTarget, Distribution.Simple.Compiler, + Distribution.Simple.Doctest, Distribution.Simple.Flag, + Distribution.Simple.Haddock, Distribution.Simple.InstallDirs, + Distribution.Simple.PackageIndex, Distribution.Simple.Program.Find, + Distribution.Simple.Program.GHC, Distribution.Simple.Program.Types, + Distribution.Simple.Setup, Distribution.System, + Distribution.Types.AbiDependency, Distribution.Types.AbiHash, + Distribution.Types.Benchmark, + Distribution.Types.BenchmarkInterface, + Distribution.Types.BenchmarkType, Distribution.Types.BuildInfo, + Distribution.Types.BuildType, Distribution.Types.ComponentId, + Distribution.Types.ComponentLocalBuildInfo, + Distribution.Types.ComponentName, + Distribution.Types.ComponentRequestedSpec, + Distribution.Types.CondTree, Distribution.Types.Condition, + Distribution.Types.Dependency, Distribution.Types.ExeDependency, + Distribution.Types.Executable, Distribution.Types.ExecutableScope, + Distribution.Types.ExposedModule, Distribution.Types.ForeignLib, + Distribution.Types.ForeignLibOption, + Distribution.Types.ForeignLibType, + Distribution.Types.GenericPackageDescription, + Distribution.Types.IncludeRenaming, + Distribution.Types.InstalledPackageInfo, + Distribution.Types.LegacyExeDependency, Distribution.Types.Library, + Distribution.Types.LocalBuildInfo, Distribution.Types.Mixin, + Distribution.Types.Module, Distribution.Types.ModuleReexport, + Distribution.Types.ModuleRenaming, + Distribution.Types.MungedPackageId, + Distribution.Types.MungedPackageName, + Distribution.Types.PackageDescription, + Distribution.Types.PackageId, Distribution.Types.PackageName, + Distribution.Types.PkgconfigDependency, + Distribution.Types.PkgconfigName, + Distribution.Types.SetupBuildInfo, Distribution.Types.SourceRepo, + Distribution.Types.TargetInfo, Distribution.Types.TestSuite, + Distribution.Types.TestSuiteInterface, Distribution.Types.TestType, + Distribution.Types.UnitId, Distribution.Types.UnqualComponentName, + Distribution.Types.Version, Distribution.Types.VersionRange, + Distribution.Utils.ShortText, Distribution.Verbosity, + Language.Haskell.Extension, Control.Applicative, Data.Complex, + Data.Functor.Compose, Data.Functor.Const, Data.Functor.Identity, + Data.Functor.Product, Data.Functor.Sum, Data.Monoid, + Data.Semigroup, Data.Semigroup.Internal, Data.Version, Data.Void, + GHC.Exts, GHC.Generics, GHC.IO.Exception, Data.Graph, + Data.IntMap.Internal, Data.IntSet.Internal, Data.Map.Internal, + Data.Sequence.Internal, Data.Set.Internal, Data.Tree, + Text.PrettyPrint.Annotated.HughesPJ, Text.PrettyPrint.HughesPJ, + Data.Text, Data.Text.Lazy] + [] *** unexpected failure for recomp007(normal) }}} **T14702** {{{ Wrong exit code for T14702(threaded1)(expected 0 , actual 1 ) Stderr ( T14702 ): T14702: unknown RTS option: -N8 T14702: T14702: Usage: <prog> <args> [+RTS <rtsopts> | -RTS <args>] ... --RTS <args> T14702: T14702: +RTS Indicates run time system options follow T14702: -RTS Indicates program arguments follow T14702: --RTS Indicates that ALL subsequent arguments will be given to the T14702: program (including any of these RTS flags) T14702: T14702: The following run time system options are available: T14702: T14702: -? Prints this message and exits; the program is not executed T14702: --info Print information about the RTS used by this program T14702: T14702: -K<size> Sets the maximum stack size (default: 80% of the heap) T14702: Egs: -K32k -K512k -K8M T14702: -ki<size> Sets the initial thread stack size (default 1k) Egs: -ki4k -ki2m T14702: -kc<size> Sets the stack chunk size (default 32k) T14702: -kb<size> Sets the stack chunk buffer size (default 1k) T14702: T14702: -A<size> Sets the minimum allocation area size (default 1m) Egs: -A20m -A10k T14702: -AL<size> Sets the amount of large-object memory that can be allocated T14702: before a GC is triggered (default: the value of -A) T14702: -n<size> Allocation area chunk size (0 = disabled, default: 0) T14702: -O<size> Sets the minimum size of the old generation (default 1M) T14702: -M<size> Sets the maximum heap size (default unlimited) Egs: -M256k -M1G T14702: -H<size> Sets the minimum heap size (default 0M) Egs: -H24m -H1G T14702: -xb<addr> Sets the address from which a suitable start for the heap memory T14702: will be searched from. This is useful if the default address T14702: clashes with some third-party library. T14702: -m<n> Minimum % of heap which must be available (default 3%) T14702: -G<n> Number of generations (default: 2) T14702: -c<n> Use in-place compaction instead of copying in the oldest generation T14702: when live data is at least <n>% of the maximum heap size set with T14702: -M (default: 30%) T14702: -c Use in-place compaction for all oldest generation collections T14702: (the default is to use copying) T14702: -w Use mark-region for the oldest generation (experimental) T14702: -I<sec> Perform full GC after <sec> idle time (default: 0.3, 0 == off) T14702: T14702: -T Collect GC statistics (useful for in-program statistics access) T14702: -t[<file>] One-line GC statistics (if <file> omitted, uses stderr) T14702: -s[<file>] Summary GC statistics (if <file> omitted, uses stderr) T14702: -S[<file>] Detailed GC statistics (if <file> omitted, uses stderr) T14702: T14702: T14702: -Z Don't squeeze out update frames on stack overflow T14702: -B Sound the bell at the start of each garbage collection T14702: T14702: -hT Produce a heap profile grouped by closure type T14702: -l[flags] Log events in binary format to the file <program>.eventlog T14702: -v[flags] Log events to stderr T14702: where [flags] can contain: T14702: s scheduler events T14702: g GC and heap events T14702: p par spark events (sampled) T14702: f par spark events (full detail) T14702: u user events (emitted from Haskell code) T14702: a all event classes above T14702: t add time stamps (only useful with -v) T14702: -x disable an event class, for any flag above T14702: the initial enabled event classes are 'sgpu' T14702: T14702: -h Heap residency profile (output file <program>.hp) T14702: -i<sec> Time between heap profile samples (seconds, default: 0.1) T14702: T14702: -r<file> Produce ticky-ticky statistics (with -rstderr for stderr) T14702: T14702: -C<secs> Context-switch interval in seconds. T14702: 0 or no argument means switch as often as possible. T14702: Default: 0.02 sec. T14702: -V<secs> Master tick interval in seconds (0 == disable timer). T14702: This sets the resolution for -C and the heap profile timer -i, T14702: and is the frequency of time profile samples. T14702: Default: 0.01 sec. T14702: T14702: -Ds DEBUG: scheduler T14702: -Di DEBUG: interpreter T14702: -Dw DEBUG: weak T14702: -DG DEBUG: gccafs T14702: -Dg DEBUG: gc T14702: -Db DEBUG: block T14702: -DS DEBUG: sanity T14702: -Dt DEBUG: stable T14702: -Dp DEBUG: prof T14702: -Da DEBUG: apply T14702: -Dl DEBUG: linker T14702: -Dm DEBUG: stm T14702: -Dz DEBUG: stack squeezing T14702: -Dc DEBUG: program coverage T14702: -Dr DEBUG: sparks T14702: -DC DEBUG: compact T14702: T14702: NOTE: DEBUG events are sent to stderr by default; add -l to create a T14702: binary event log file instead. T14702: T14702: --install-signal-handlers=<yes|no> T14702: Install signal handlers (default: yes) T14702: -e<n> Maximum number of outstanding local sparks (default: 4096) T14702: -xm Base address to mmap memory in the GHCi linker T14702: (hex; must be <80000000) T14702: -xq The allocation limit given to a thread after it receives T14702: an AllocationLimitExceeded exception. (default: 100k) T14702: T14702: -Mgrace=<n> T14702: The amount of allocation after the program receives a T14702: HeapOverflow exception before the exception is thrown again, if T14702: the program is still exceeding the heap limit. T14702: T14702: RTS options may also be specified using the GHCRTS environment variable. T14702: T14702: Other RTS options may be available for programs compiled a different way. T14702: The GHC User's Guide has full details. T14702: *** unexpected failure for T14702(threaded1) }}} **nursery-chunks1** {{{ Actual stderr output differs from expected: --- /dev/null 2018-08-01 14:11:13.420752000 +0000 +++ ./rts/nursery-chunks1.run/nursery-chunks1.run.stderr.normalised 2018-08-02 03:45:18.786560729 +0000 @@ -0,0 +1,3 @@ +nursery-chunks1: setNumCapabilities: not supported on this platform +nursery-chunks1: setNumCapabilities: not supported on this platform +nursery-chunks1: setNumCapabilities: not supported on this platform *** unexpected failure for nursery-chunks1(threaded1) }}} **numa001** {{{ Wrong exit code for numa001(debug_numa)(expected 0 , actual 1 ) Stderr ( numa001 ): numa001: unknown RTS option: -N2 numa001: numa001: Usage: <prog> <args> [+RTS <rtsopts> | -RTS <args>] ... --RTS <args> numa001: numa001: +RTS Indicates run time system options follow numa001: -RTS Indicates program arguments follow numa001: --RTS Indicates that ALL subsequent arguments will be given to the numa001: program (including any of these RTS flags) numa001: numa001: The following run time system options are available: numa001: numa001: -? Prints this message and exits; the program is not executed numa001: --info Print information about the RTS used by this program numa001: numa001: -K<size> Sets the maximum stack size (default: 80% of the heap) numa001: Egs: -K32k -K512k -K8M numa001: -ki<size> Sets the initial thread stack size (default 1k) Egs: -ki4k -ki2m numa001: -kc<size> Sets the stack chunk size (default 32k) numa001: -kb<size> Sets the stack chunk buffer size (default 1k) numa001: numa001: -A<size> Sets the minimum allocation area size (default 1m) Egs: -A20m -A10k numa001: -AL<size> Sets the amount of large-object memory that can be allocated numa001: before a GC is triggered (default: the value of -A) numa001: -n<size> Allocation area chunk size (0 = disabled, default: 0) numa001: -O<size> Sets the minimum size of the old generation (default 1M) numa001: -M<size> Sets the maximum heap size (default unlimited) Egs: -M256k -M1G numa001: -H<size> Sets the minimum heap size (default 0M) Egs: -H24m -H1G numa001: -xb<addr> Sets the address from which a suitable start for the heap memory numa001: will be searched from. This is useful if the default address numa001: clashes with some third-party library. numa001: -m<n> Minimum % of heap which must be available (default 3%) numa001: -G<n> Number of generations (default: 2) numa001: -c<n> Use in-place compaction instead of copying in the oldest generation numa001: when live data is at least <n>% of the maximum heap size set with numa001: -M (default: 30%) numa001: -c Use in-place compaction for all oldest generation collections numa001: (the default is to use copying) numa001: -w Use mark-region for the oldest generation (experimental) numa001: -I<sec> Perform full GC after <sec> idle time (default: 0.3, 0 == off) numa001: numa001: -T Collect GC statistics (useful for in-program statistics access) numa001: -t[<file>] One-line GC statistics (if <file> omitted, uses stderr) numa001: -s[<file>] Summary GC statistics (if <file> omitted, uses stderr) numa001: -S[<file>] Detailed GC statistics (if <file> omitted, uses stderr) numa001: numa001: numa001: -Z Don't squeeze out update frames on stack overflow numa001: -B Sound the bell at the start of each garbage collection numa001: numa001: -hT Produce a heap profile grouped by closure type numa001: -l[flags] Log events in binary format to the file <program>.eventlog numa001: -v[flags] Log events to stderr numa001: where [flags] can contain: numa001: s scheduler events numa001: g GC and heap events numa001: p par spark events (sampled) numa001: f par spark events (full detail) numa001: u user events (emitted from Haskell code) numa001: a all event classes above numa001: t add time stamps (only useful with -v) numa001: -x disable an event class, for any flag above numa001: the initial enabled event classes are 'sgpu' numa001: numa001: -h Heap residency profile (output file <program>.hp) numa001: -i<sec> Time between heap profile samples (seconds, default: 0.1) numa001: numa001: -r<file> Produce ticky-ticky statistics (with -rstderr for stderr) numa001: numa001: -C<secs> Context-switch interval in seconds. numa001: 0 or no argument means switch as often as possible. numa001: Default: 0.02 sec. numa001: -V<secs> Master tick interval in seconds (0 == disable timer). numa001: This sets the resolution for -C and the heap profile timer -i, numa001: and is the frequency of time profile samples. numa001: Default: 0.01 sec. numa001: numa001: -Ds DEBUG: scheduler numa001: -Di DEBUG: interpreter numa001: -Dw DEBUG: weak numa001: -DG DEBUG: gccafs numa001: -Dg DEBUG: gc numa001: -Db DEBUG: block numa001: -DS DEBUG: sanity numa001: -Dt DEBUG: stable numa001: -Dp DEBUG: prof numa001: -Da DEBUG: apply numa001: -Dl DEBUG: linker numa001: -Dm DEBUG: stm numa001: -Dz DEBUG: stack squeezing numa001: -Dc DEBUG: program coverage numa001: -Dr DEBUG: sparks numa001: -DC DEBUG: compact numa001: numa001: NOTE: DEBUG events are sent to stderr by default; add -l to create a numa001: binary event log file instead. numa001: numa001: --install-signal-handlers=<yes|no> numa001: Install signal handlers (default: yes) numa001: -e<n> Maximum number of outstanding local sparks (default: 4096) numa001: -xm Base address to mmap memory in the GHCi linker numa001: (hex; must be <80000000) numa001: -xq The allocation limit given to a thread after it receives numa001: an AllocationLimitExceeded exception. (default: 100k) numa001: numa001: -Mgrace=<n> numa001: The amount of allocation after the program receives a numa001: HeapOverflow exception before the exception is thrown again, if numa001: the program is still exceeding the heap limit. numa001: numa001: RTS options may also be specified using the GHCRTS environment variable. numa001: numa001: Other RTS options may be available for programs compiled a different way. numa001: The GHC User's Guide has full details. numa001: *** unexpected failure for numa001(debug_numa) }}} **T11760** {{{ Wrong exit code for T11760(normal)(expected 0 , actual 1 ) Stderr ( T11760 ): T11760: unknown RTS option: -N2 T11760: T11760: Usage: <prog> <args> [+RTS <rtsopts> | -RTS <args>] ... --RTS <args> T11760: T11760: +RTS Indicates run time system options follow T11760: -RTS Indicates program arguments follow T11760: --RTS Indicates that ALL subsequent arguments will be given to the T11760: program (including any of these RTS flags) T11760: T11760: The following run time system options are available: T11760: T11760: -? Prints this message and exits; the program is not executed T11760: --info Print information about the RTS used by this program T11760: T11760: -K<size> Sets the maximum stack size (default: 80% of the heap) T11760: Egs: -K32k -K512k -K8M T11760: -ki<size> Sets the initial thread stack size (default 1k) Egs: -ki4k -ki2m T11760: -kc<size> Sets the stack chunk size (default 32k) T11760: -kb<size> Sets the stack chunk buffer size (default 1k) T11760: T11760: -A<size> Sets the minimum allocation area size (default 1m) Egs: -A20m -A10k T11760: -AL<size> Sets the amount of large-object memory that can be allocated T11760: before a GC is triggered (default: the value of -A) T11760: -n<size> Allocation area chunk size (0 = disabled, default: 0) T11760: -O<size> Sets the minimum size of the old generation (default 1M) T11760: -M<size> Sets the maximum heap size (default unlimited) Egs: -M256k -M1G T11760: -H<size> Sets the minimum heap size (default 0M) Egs: -H24m -H1G T11760: -xb<addr> Sets the address from which a suitable start for the heap memory T11760: will be searched from. This is useful if the default address T11760: clashes with some third-party library. T11760: -m<n> Minimum % of heap which must be available (default 3%) T11760: -G<n> Number of generations (default: 2) T11760: -c<n> Use in-place compaction instead of copying in the oldest generation T11760: when live data is at least <n>% of the maximum heap size set with T11760: -M (default: 30%) T11760: -c Use in-place compaction for all oldest generation collections T11760: (the default is to use copying) T11760: -w Use mark-region for the oldest generation (experimental) T11760: -I<sec> Perform full GC after <sec> idle time (default: 0.3, 0 == off) T11760: T11760: -T Collect GC statistics (useful for in-program statistics access) T11760: -t[<file>] One-line GC statistics (if <file> omitted, uses stderr) T11760: -s[<file>] Summary GC statistics (if <file> omitted, uses stderr) T11760: -S[<file>] Detailed GC statistics (if <file> omitted, uses stderr) T11760: T11760: T11760: -Z Don't squeeze out update frames on stack overflow T11760: -B Sound the bell at the start of each garbage collection T11760: T11760: -hT Produce a heap profile grouped by closure type T11760: -h Heap residency profile (output file <program>.hp) T11760: -i<sec> Time between heap profile samples (seconds, default: 0.1) T11760: T11760: -C<secs> Context-switch interval in seconds. T11760: 0 or no argument means switch as often as possible. T11760: Default: 0.02 sec. T11760: -V<secs> Master tick interval in seconds (0 == disable timer). T11760: This sets the resolution for -C and the heap profile timer -i, T11760: and is the frequency of time profile samples. T11760: Default: 0.01 sec. T11760: T11760: --install-signal-handlers=<yes|no> T11760: Install signal handlers (default: yes) T11760: -e<n> Maximum number of outstanding local sparks (default: 4096) T11760: -xm Base address to mmap memory in the GHCi linker T11760: (hex; must be <80000000) T11760: -xq The allocation limit given to a thread after it receives T11760: an AllocationLimitExceeded exception. (default: 100k) T11760: T11760: -Mgrace=<n> T11760: The amount of allocation after the program receives a T11760: HeapOverflow exception before the exception is thrown again, if T11760: the program is still exceeding the heap limit. T11760: T11760: RTS options may also be specified using the GHCRTS environment variable. T11760: T11760: Other RTS options may be available for programs compiled a different way. T11760: The GHC User's Guide has full details. T11760: *** unexpected failure for T11760(normal) }}} -- Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/15466> GHC <http://www.haskell.org/ghc/> The Glasgow Haskell Compiler

1 6

[GHC] #10854: Remove recursive uses of `pprParendHsExpr` from `HsExpr.ppr_expr`
by GHC 15 Nov '18

15 Nov '18

#10854: Remove recursive uses of `pprParendHsExpr` from `HsExpr.ppr_expr` -------------------------------------+------------------------------------- Reporter: goldfire | Owner: Type: task | Status: new Priority: normal | Milestone: Component: Compiler | Version: 7.10.2 Keywords: newcomer | Operating System: Unknown/Multiple Architecture: | Type of failure: None/Unknown Unknown/Multiple | Test Case: | Blocked By: Blocking: | Related Tickets: Differential Revisions: | -------------------------------------+------------------------------------- An `HsExpr` should look exactly as a user wrote some Haskell code. Its pretty printer should therefore be quite dumb. Just print out the code! But a few places in GHC create `HsExpr`s and aren't scrupulous with regard to adding `HsPar` nodes where source syntax would need them. Thus, well- meaning souls have added `pprParendExpr` calls to the `HsExpr` pretty- printer to try to cover these cases. Simon and I [https://phabricator.haskell.org/D1219#34199 think] that we should remove all recursive uses of `pprParendExpr` from the `HsExpr` pretty-printer and instead add the `HsPar`s where necessary. It was recently reported that the following test cases break when simply removing `pprParendExpr`: {{{ Unexpected failures: deriving/should_fail T4846 [stderr mismatch] (normal) generics GenDerivOutput [stderr mismatch] (normal) generics GenDerivOutput1_0 [stderr mismatch] (normal) generics GenDerivOutput1_1 [stderr mismatch] (normal) ghci/scripts T10248 [bad stderr] (ghci) indexed-types/should_compile PushedInAsGivens [stderr mismatch] (normal) safeHaskell/safeLanguage SafeLang10 [stderr mismatch] (normal) safeHaskell/safeLanguage SafeLang17 [stderr mismatch] (normal) typecheck/should_fail T8603 [stderr mismatch] (normal) typecheck/should_fail tcfail177 [stderr mismatch] (normal) }}} See also considerable commentary on Phab:D1114. -- Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/10854> GHC <http://www.haskell.org/ghc/> The Glasgow Haskell Compiler

1 6

[GHC] #14293: View patterns with locally defined functions in restructuring don't compile
by GHC 14 Nov '18

14 Nov '18

#14293: View patterns with locally defined functions in restructuring don't compile -------------------------------------+------------------------------------- Reporter: heisenbug | Owner: (none) Type: bug | Status: new Priority: normal | Milestone: Component: Compiler | Version: 8.2.1 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: -------------------------------------+------------------------------------- {{{#!hs {-# LANGUAGE ViewPatterns #-} foo x = x Just (id -> res) = pure 'a' -- WORKS Just (foo -> res') = pure 'a' -- FAILS bar (foo -> res) = res -- WORKS {- [1 of 1] Compiling Main ( T14293.hs, interpreted ) T14293.hs:6:7-9: error: Variable not in scope: foo :: Char -> t | 6 | Just (foo -> res') = pure 'a' | ^^^ Failed, 0 modules loaded. -} }}} -- Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/14293> GHC <http://www.haskell.org/ghc/> The Glasgow Haskell Compiler

1 4

[GHC] #13114: UniqSet definition seems shady
by GHC 13 Nov '18

13 Nov '18

#13114: UniqSet definition seems shady -------------------------------------+------------------------------------- Reporter: dfeuer | Owner: dfeuer Type: task | Status: new Priority: low | Milestone: 8.4.1 Component: Compiler | Version: 8.1 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: -------------------------------------+------------------------------------- Currently, {{{#!hs type UniqSet a = UniqFM a }}} The key invariant of `UniqSet` is expressed in the somewhat-poorly-named `Note [Unsound mapUniqSet]`, and not enforced by the types. It seems likely that the clean thing is {{{#!hs newtype UniqSet a = US (UniqFM a) }}} Unfortunately there's an awful lot of code using `UniqSet` and assuming it's the same as `UniqFM`. To make this work, we'd need to expand the `UniqSet` API somewhat and figure out what to do at use sites using it interchangeably with `UniqFM`. -- Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/13114> GHC <http://www.haskell.org/ghc/> The Glasgow Haskell Compiler

1 3

[GHC] #15832: returnIO/bindIO destroys runtime explicit stack information in some cases
by GHC 12 Nov '18

12 Nov '18

#15832: returnIO/bindIO destroys runtime explicit stack information in some cases -------------------------------------+------------------------------------- Reporter: infinity0 | Owner: (none) Type: bug | Status: new Priority: normal | Milestone: Component: Compiler | Version: 8.6.1 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: -------------------------------------+------------------------------------- Tested in GHC 8.2.2, 8.4.3 and 8.6.1: Test-good.hs {{{#!hs import GHC.Base data X = X Int deriving (Eq, Show) main :: IO () main = (returnIO undefined) `bindIO` (const (print $ X (error "XXX"))) }}} Test-bad.hs {{{#!hs import GHC.Base data X = X Int deriving (Eq, Show) main :: IO () main = (returnIO undefined) `bindIO` (\_ -> (print $ X (error "XXX"))) }}} build.sh {{{#!shell #!/bin/sh set -e p="${1:-stg}" for i in good bad; do rm -rf ghc*_* Test-$i Test-$i.dump-* Test-$i.hi Test-$i.o ghc "-ddump-$p" -dsuppress-module-prefixes -dsuppress-uniques \ -keep-tmp-files -dumpdir . -ddump-to-file \ -fno-cse -prof -fprof-auto -fprof-auto-calls -fprof-cafs \ -dinitial-unique=0 -dunique-increment=1 \ Test-$i.hs ./Test-$i +RTS -xc || true done colordiff -ruw Test-*.dump-"$p" | less -R }}} Running `sh build.sh` gives the following output: {{{ [1 of 1] Compiling Main ( Test-good.hs, Test-good.o ) Linking Test-good ... *** Exception (reporting due to +RTS -xc): (THUNK_2_0), stack trace: Main.main, called from Main.main, called from Main.main, called from Main.main, called from Main.main, called from Main.CAF:main --> evaluated by: Main.main, called from Main.main, called from Main.main, called from Main.CAF:main --> evaluated by: Main.main, called from Main.main, called from Main.main Test-good: XXX CallStack (from HasCallStack): error, called at Test-good.hs:6:57 in main:Main CallStack (from -prof): Main.main (Test-good.hs:6:57-67) Main.main (Test-good.hs:6:54-68) Main.main (Test-good.hs:6:46-68) Main.main (Test-good.hs:6:39-69) Main.main (Test-good.hs:6:8-70) Main.CAF:main (Test-good.hs:6:1-4) [1 of 1] Compiling Main ( Test-bad.hs, Test-bad.o ) Linking Test-bad ... *** Exception (reporting due to +RTS -xc): (THUNK_2_0), stack trace: Main.main, called from Main.main, called from Main.main, called from Main.main Test-bad: XXX CallStack (from HasCallStack): error, called at Test-bad.hs:6:57 in main:Main CallStack (from -prof): Main.main (Test-bad.hs:6:57-67) Main.main (Test-bad.hs:6:54-68) Main.main (Test-bad.hs:6:46-68) Main.main (Test-bad.hs:6:8-70) }}} As you can see, in Test-bad.hs all the entries below "evaluated by" are missing. I am not familiar with STG output, but running the script also shows you a diff of the STG dump. It seems innocent enough. Running `sh build.sh cmm` shows many more differences. -- Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/15832> GHC <http://www.haskell.org/ghc/> The Glasgow Haskell Compiler

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[GHC] #15054: ghc internal error appeared in GHCI
by GHC 12 Nov '18

12 Nov '18

#15054: ghc internal error appeared in GHCI -------------------------------------+------------------------------------- Reporter: radrow | Owner: (none) Type: bug | Status: new Priority: normal | Milestone: 8.6.1 Component: GHCi | Version: 8.2.2 Keywords: | Operating System: Unknown/Multiple Architecture: x86_64 | Type of failure: None/Unknown (amd64) | Test Case: | Blocked By: Blocking: | Related Tickets: Differential Rev(s): | Wiki Page: -------------------------------------+------------------------------------- After playing with vectors in ghci I got following error: {{{ ghc: internal error: Unable to commit 1048576 bytes of memory }}} It happened randomly, on empty prompt while no query was being evaluated I am using latest version of GHC on Arch Linux Here is my whole session: {{{ >λ= import Criterion Criterion Criterion.IO.Printf Criterion.Main.Options Criterion.Report Criterion.Analysis Criterion.Internal Criterion.Measurement Criterion.Types Criterion.IO Criterion.Main Criterion.Monad >λ= import Criterion.Main >λ= import Data.Vector >λ= import Data.Vector as V >λ= main = default defaultConfig defaultMain defaultMainWith >λ= defaultMain [bench "TESTXD" $ whnf ([1..100000]!!) 9999] benchmarking TESTXD time 19.81 μs (19.66 μs .. 19.99 μs) 0.999 R² (0.999 R² .. 1.000 R²) mean 13.47 μs (12.93 μs .. 14.11 μs) std dev 853.8 ns (542.7 ns .. 1.249 μs) variance introduced by outliers: 65% (severely inflated) >λ= defaultMain [bench "TESTXD" $ whnf ([1..100000]!!) 9999] benchmarking TESTXD time 19.62 μs (19.39 μs .. 19.99 μs) 0.999 R² (0.998 R² .. 1.000 R²) mean 13.49 μs (12.85 μs .. 14.51 μs) std dev 1.154 μs (524.9 ns .. 1.704 μs) variance introduced by outliers: 77% (severely inflated) >λ= v = V.fromList [1..100000] Display all 192 possibilities? (y or n) V.! V.fold1M' V.indexed V.prescanl V.unsafeDrop V.!? V.fold1M'_ V.init V.prescanl' V.unsafeFreeze V.++ V.fold1M_ V.iscanl V.prescanr V.unsafeHead V.// V.foldM V.iscanl' V.prescanr' V.unsafeHeadM V.MVector V.foldM' V.iscanr V.product V.unsafeIndex V.Vector V.foldM'_ V.iscanr' V.replicate V.unsafeIndexM V.accum V.foldM_ V.iterateN V.replicateM V.unsafeInit V.accumulate V.foldl V.iterateNM V.reverse V.unsafeLast V.accumulate_ V.foldl' V.izipWith V.scanl V.unsafeLastM V.all V.foldl1 V.izipWith3 V.scanl' V.unsafeSlice V.and V.foldl1' V.izipWith4 V.scanl1 V.unsafeTail V.any V.foldr V.izipWith5 V.scanl1' V.unsafeTake V.backpermute V.foldr' V.izipWith6 V.scanr V.unsafeThaw V.break V.foldr1 V.izipWithM V.scanr' V.unsafeUpd V.concat V.foldr1' V.izipWithM_ V.scanr1 V.unsafeUpdate V.concatMap V.forM V.last V.scanr1' V.unsafeUpdate_ V.cons V.forM_ V.lastM V.sequence V.unstablePartition V.constructN V.force V.length V.sequence_ V.unzip V.constructrN V.freeze V.map V.singleton V.unzip3 V.convert V.fromList V.mapM V.slice V.unzip4 V.copy V.fromListN V.mapM_ V.snoc V.unzip5 V.create V.generate V.mapMaybe V.span V.unzip6 V.createT V.generateM V.maxIndex V.splitAt V.update V.drop V.head V.maxIndexBy V.sum V.update_ V.dropWhile V.headM V.maximum V.tail V.zip V.elem V.ifilter V.maximumBy V.take V.zip3 V.elemIndex V.ifoldM V.minIndex V.takeWhile V.zip4 V.elemIndices V.ifoldM' V.minIndexBy V.thaw V.zip5 V.empty V.ifoldM'_ V.minimum V.toList V.zip6 V.enumFromN V.ifoldM_ V.minimumBy V.unfoldr V.zipWith V.enumFromStepN V.ifoldl V.modify V.unfoldrM V.zipWith3 V.enumFromThenTo V.ifoldl' V.notElem V.unfoldrN V.zipWith4 V.enumFromTo V.ifoldr V.null V.unfoldrNM V.zipWith5 V.filter V.ifoldr' V.or V.uniq V.zipWith6 V.filterM V.imap V.partition V.unsafeAccum V.zipWithM V.find V.imapM V.postscanl V.unsafeAccumulate V.zipWithM_ V.findIndex V.imapM_ V.postscanl' V.unsafeAccumulate_ V.findIndices V.imapMaybe V.postscanr V.unsafeBackpermute V.fold1M V.indexM V.postscanr' V.unsafeCopy >λ= defaultMain [bench "TESTXD" $ whnf ([1..100000]!!) 9999, bench "TESTV" $ whnf (\x -> (V.!) v x)] <interactive>:8:93: error: parse error (possibly incorrect indentation or mismatched brackets) ] λ= defaultMain [bench "TESTXD" $ whnf ([1..100000]!!) 9999, bench "TESTV" $ whnf (\x -> (V.!) v x) <interactive>:9:74: error: • Couldn't match expected type ‘Benchmarkable’ with actual type ‘Int -> Benchmarkable’ • Probable cause: ‘whnf’ is applied to too few arguments In the second argument of ‘($)’, namely ‘whnf (\ x -> (!) v x)’ In the expression: bench "TESTV" $ whnf (\ x -> (!) v x) In the first argument of ‘defaultMain’, namely ‘[bench "TESTXD" $ whnf ([1 .. 100000] !!) 9999, >λ= defaultMain [bench "TESTXD" $ whnf ([1..100000]!!) 9999, bench "TESTV" $ whnf (\x -> (V.!) v x) 9999] benchmarking TESTXD time 20.61 μs (20.47 μs .. 20.80 μs) 0.999 R² (0.999 R² .. 1.000 R²) mean 14.41 μs (13.85 μs .. 14.88 μs) std dev 805.2 ns (588.3 ns .. 1.036 μs) variance introduced by outliers: 59% (severely inflated) benchmarking TESTV time 1.796 ms (1.768 ms .. 1.831 ms) 0.997 R² (0.995 R² .. 0.999 R²) mean 1.426 ms (1.367 ms .. 1.481 ms) std dev 153.6 μs (123.2 μs .. 190.1 μs) variance introduced by outliers: 69% (severely inflated) (V.!) >λ= >λ= (V.!) v 999 1000 >λ= (V.!) v 9999 10000 >λ= l = [1..100000]) <interactive>:13:16: error: parse error on input ‘)’ >λ= l = [1..100000] >λ= l !! 9999 10000 >λ= l !! 99999 100000 >λ= l !! 999999 *** Exception: Prelude.!!: index too large >λ= l = [1..10000000] >λ= l !! 999999 1000000 >λ= l !! 9999999 10000000 >λ= l !! 99999999 *** Exception: Prelude.!!: index too large >λ= sum l <interactive>:22:1: error: Ambiguous occurrence ‘sum’ It could refer to either ‘Data.Vector.sum’, imported from ‘Data.Vector’ or ‘Prelude.sum’, imported from ‘Prelude’ (and originally defined in ‘Data.Foldable’) >λ= Prelude.sum l 50000005000000 >λ= Prelude.sum l 50000005000000 >λ= v = V.fr V.freeze V.fromList V.fromListN >λ= v = V.fromList l >λ= V.last v 10000000 >λ= :sprint v v = _ Display all 1088 possibilities? (y or n) >λ= V.sum v 50000005000000 >λ= V.sum v 50000005000000 >λ= V.last v 10000000 >λ= relast l read readIO readLn reads realToFrac rem replicate return readFile readList readParen readsPrec recip repeat replicateM reverse >λ= Prelude.last l 10000000 >λ= Prelude.last l 10000000 >λ= V.last v 10000000 >λ= :t (//) (//) :: Vector a -> [(Int, a)] -> Vector a >λ= :t v v :: (Enum a, Num a) => Vector a >λ= l = [1..10000000] :: [Int] >λ= last l <interactive>:37:1: error: Ambiguous occurrence ‘last’ It could refer to either ‘Data.Vector.last’, imported from ‘Data.Vector’ or ‘Prelude.last’, imported from ‘Prelude’ (and originally defined in ‘GHC.List’) >λ= import Prelude as P >λ= P.last l 10000000 >λ= v = from fromEnum fromInteger fromIntegral fromList fromListN fromRational >λ= v = fromList l >λ= :t v v :: Vector Int >λ= V.last v 10000000 >λ= V.last v 10000000 >λ= V.last v 10000000 >λ= v = fromList l >λ= P.last l 10000000 >λ= P.last l 10000000 >λ= V.last v 10000000 >λ= V.last v 10000000 >λ= V.last v 10000000 >λ= P.last l 10000000 >λ= P.last l 10000000 >λ= l = [1..100000000] :: [Int] >λ= v = fromList l >λ= P.last l 100000000 >λ= V.last v 100000000 >λ= V.last v 100000000 >λ= :t v v :: Vector Int >λ= :t v v :: Vector Int >λ= :sprint v v = Data.Vector.Vector 0 100000000 _ >λ= ghc: internal error: Unable to commit 1048576 bytes of memory (GHC version 8.2.2 for x86_64_unknown_linux) Please report this as a GHC bug: http://www.haskell.org/ghc/reportabug [1] 12349 killed stack ghci }}} -- Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/15054> GHC <http://www.haskell.org/ghc/> The Glasgow Haskell Compiler

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