June 2017 - ghc-tickets

[GHC] #12002: Pragmas after a module declaration are ignored without warning.
by GHC 08 Aug '18

08 Aug '18

#12002: Pragmas after a module declaration are ignored without warning. -------------------------------------+------------------------------------- Reporter: seanparsons | Owner: Type: bug | Status: new Priority: normal | Milestone: Component: Compiler | Version: 7.10.3 Keywords: | Operating System: Unknown/Multiple Architecture: | Type of failure: Other Unknown/Multiple | Test Case: | Blocked By: Blocking: | Related Tickets: Differential Rev(s): | Wiki Page: -------------------------------------+------------------------------------- Normally pragmas are placed above the module declaration like so: {{{#!hs {-# LANGUAGE OverloadedStrings #-} module Main where }}} However if the above 2 lines are flipped around like this: {{{#!hs module Main where {-# LANGUAGE OverloadedStrings #-} }}} Then the behaviour seen by a user is that equivalent to the pragma not being present, because it would appear GHC ignores the multi-line comment it looks like. For a novice (I'm not one but it just tripped me up) this would be incredibly baffling (it was for me), it would be nice to see a warning for this at the least. -- Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/12002> GHC <http://www.haskell.org/ghc/> The Glasgow Haskell Compiler

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[GHC] #12043: internal error: evacuate: strange closure type
by GHC 08 Aug '18

08 Aug '18

#12043: internal error: evacuate: strange closure type -------------------------------------+------------------------------------- Reporter: mattchan | Owner: Type: bug | Status: new Priority: normal | Milestone: Research needed Component: Compiler | Version: 7.10.3 Keywords: internal | Operating System: Unknown/Multiple error, strange closuren | Architecture: ia64 | Type of failure: None/Unknown Test Case: | Blocked By: Blocking: | Related Tickets: Differential Rev(s): | Wiki Page: -------------------------------------+------------------------------------- Scary error while building Liquid Haskell from source: {{{ $ stack install [truncated] text-1.2.2.1: copy/register Progress: 40/61 -- While building package Cabal-1.22.8.0 using: /Users/matt/.stack/setup-exe-cache/x86_64-osx/setup-Simple- Cabal-1.22.5.0-ghc-7.10.3 --builddir=.stack- work/dist/x86_64-osx/Cabal-1.22.5.0 build --ghc-options " -ddump-hi -ddump-to-file" Process exited with code: ExitFailure (-6) Logs have been written to: /Users/matt/liquid/liquidhaskell/.stack- work/logs/Cabal-1.22.8.0.log Configuring Cabal-1.22.8.0... Building Cabal-1.22.8.0... Preprocessing library Cabal-1.22.8.0... [ 1 of 81] Compiling Paths_Cabal ( .stack- work/dist/x86_64-osx/Cabal-1.22.5.0/build/autogen/Paths_Cabal.hs, .stack- work/dist/x86_64-osx/Cabal-1.22.5.0/build/Paths_Cabal.o ) [ 2 of 81] Compiling Distribution.TestSuite ( Distribution/TestSuite.hs, .stack- work/dist/x86_64-osx/Cabal-1.22.5.0/build/Distribution/TestSuite.o ) [ 3 of 81] Compiling Distribution.Simple.PreProcess.Unlit ( Distribution/Simple/PreProcess/Unlit.hs, .stack- work/dist/x86_64-osx/Cabal-1.22.5.0/build/Distribution/Simple/PreProcess/Unlit.o ) [ 4 of 81] Compiling Distribution.GetOpt ( Distribution/GetOpt.hs, .stack-work/dist/x86_64-osx/Cabal-1.22.5.0/build/Distribution/GetOpt.o ) [ 5 of 81] Compiling Distribution.PackageDescription.Utils ( Distribution/PackageDescription/Utils.hs, .stack- work/dist/x86_64-osx/Cabal-1.22.5.0/build/Distribution/PackageDescription/Utils.o ) [ 6 of 81] Compiling Distribution.Simple.CCompiler ( Distribution/Simple/CCompiler.hs, .stack- work/dist/x86_64-osx/Cabal-1.22.5.0/build/Distribution/Simple/CCompiler.o ) [ 7 of 81] Compiling Distribution.Compat.Binary ( Distribution/Compat/Binary.hs, .stack- work/dist/x86_64-osx/Cabal-1.22.5.0/build/Distribution/Compat/Binary.o ) [ 8 of 81] Compiling Distribution.Compat.ReadP ( Distribution/Compat/ReadP.hs, .stack- work/dist/x86_64-osx/Cabal-1.22.5.0/build/Distribution/Compat/ReadP.o ) [ 9 of 81] Compiling Distribution.Text ( Distribution/Text.hs, .stack- work/dist/x86_64-osx/Cabal-1.22.5.0/build/Distribution/Text.o ) [10 of 81] Compiling Distribution.Version ( Distribution/Version.hs, .stack-work/dist/x86_64-osx/Cabal-1.22.5.0/build/Distribution/Version.o ) [11 of 81] Compiling Language.Haskell.Extension ( Language/Haskell/Extension.hs, .stack- work/dist/x86_64-osx/Cabal-1.22.5.0/build/Language/Haskell/Extension.o ) [12 of 81] Compiling Distribution.Compiler ( Distribution/Compiler.hs, .stack-work/dist/x86_64-osx/Cabal-1.22.5.0/build/Distribution/Compiler.o ) [13 of 81] Compiling Distribution.Simple.Compiler ( Distribution/Simple/Compiler.hs, .stack- work/dist/x86_64-osx/Cabal-1.22.5.0/build/Distribution/Simple/Compiler.o ) [14 of 81] Compiling Distribution.Simple.GHC.ImplInfo ( Distribution/Simple/GHC/ImplInfo.hs, .stack- work/dist/x86_64-osx/Cabal-1.22.5.0/build/Distribution/Simple/GHC/ImplInfo.o ) [15 of 81] Compiling Distribution.License ( Distribution/License.hs, .stack-work/dist/x86_64-osx/Cabal-1.22.5.0/build/Distribution/License.o ) [16 of 81] Compiling Distribution.ModuleName ( Distribution/ModuleName.hs, .stack- work/dist/x86_64-osx/Cabal-1.22.5.0/build/Distribution/ModuleName.o ) [17 of 81] Compiling Distribution.Package ( Distribution/Package.hs, .stack-work/dist/x86_64-osx/Cabal-1.22.5.0/build/Distribution/Package.o ) [18 of 81] Compiling Distribution.System ( Distribution/System.hs, .stack-work/dist/x86_64-osx/Cabal-1.22.5.0/build/Distribution/System.o ) [19 of 81] Compiling Distribution.PackageDescription ( Distribution/PackageDescription.hs, .stack- work/dist/x86_64-osx/Cabal-1.22.5.0/build/Distribution/PackageDescription.o ) ghc: internal error: evacuate: strange closure type 41832616 (GHC version 7.10.3 for x86_64_apple_darwin) Please report this as a GHC bug: http://www.haskell.org/ghc/reportabug }}} [[Image(http://i.imgur.com/T44UPg0.png)]] -- Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/12043> GHC <http://www.haskell.org/ghc/> The Glasgow Haskell Compiler

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[GHC] #10927: IndexError: pop from empty list
by GHC 08 Aug '18

08 Aug '18

#10927: IndexError: pop from empty list -------------------------------------+------------------------------------- Reporter: schwab | Owner: hvr Type: bug | Status: new Priority: normal | Milestone: Component: Trac & Git | Version: Keywords: | Operating System: Unknown/Multiple Architecture: | Type of failure: None/Unknown Unknown/Multiple | Test Case: | Blocked By: Blocking: | Related Tickets: Differential Rev(s): | -------------------------------------+------------------------------------- ==== Zum Reproduzieren ==== Während der Ausführung von GET auf `/attachment/ticket/10926/` hat Trac einen internen Fehler gemeldet. ''(Bitte geben Sie hier weitere Details an)'' Anfrageparameter: {{{ {u'action': u'new', 'path': u'10926/', 'realm': u'ticket'} }}} User agent: `Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.21 (KHTML, like Gecko) konqueror/4.14.9 Safari/537.21` ==== Systeminformationen ==== ''Systeminformation nicht verfügbar'' ==== Aktive Plugins ==== ''Plugininformation nicht verfügbar'' ==== Python-Zurückverfolgungsinformationen ==== {{{ Traceback (most recent call last): File "/usr/local/lib/python2.7/dist- packages/Trac-1.0.9-py2.7.egg/trac/web/main.py", line 554, in _dispatch_request dispatcher.dispatch(req) File "/usr/local/lib/python2.7/dist- packages/Trac-1.0.9-py2.7.egg/trac/web/main.py", line 267, in dispatch iterable=chrome.use_chunked_encoding) File "/usr/local/lib/python2.7/dist- packages/Trac-1.0.9-py2.7.egg/trac/web/chrome.py", line 1111, in render_template encoding='utf-8') File "/usr/local/lib/python2.7/dist-packages/genshi/core.py", line 184, in render return encode(generator, method=method, encoding=encoding, out=out) File "/usr/local/lib/python2.7/dist-packages/genshi/output.py", line 58, in encode for chunk in iterator: File "/usr/local/lib/python2.7/dist-packages/genshi/output.py", line 350, in __call__ for kind, data, pos in stream: File "/usr/local/lib/python2.7/dist-packages/genshi/output.py", line 829, in __call__ for kind, data, pos in stream: File "/usr/local/lib/python2.7/dist-packages/genshi/output.py", line 669, in __call__ for kind, data, pos in stream: File "/usr/local/lib/python2.7/dist-packages/genshi/output.py", line 774, in __call__ for kind, data, pos in chain(stream, [(None, None, None)]): File "/usr/local/lib/python2.7/dist-packages/genshi/output.py", line 594, in __call__ for ev in stream: File "/usr/local/lib/python2.7/dist-packages/genshi/core.py", line 289, in _ensure for event in stream: File "/usr/local/lib/python2.7/dist-packages/genshi/core.py", line 289, in _ensure for event in stream: File "/usr/local/lib/python2.7/dist- packages/Trac-1.0.9-py2.7.egg/trac/web/chrome.py", line 1309, in _strip_accesskeys for kind, data, pos in stream: File "/usr/local/lib/python2.7/dist-packages/genshi/core.py", line 289, in _ensure for event in stream: File "/usr/local/lib/python2.7/dist- packages/Trac-1.0.9-py2.7.egg/trac/web/chrome.py", line 1298, in _generate for kind, data, pos in stream: File "/usr/local/lib/python2.7/dist-packages/genshi/core.py", line 289, in _ensure for event in stream: File "/usr/local/lib/python2.7/dist-packages/genshi/core.py", line 289, in _ensure for event in stream: File "/usr/local/lib/python2.7/dist- packages/genshi/filters/transform.py", line 706, in _unmark for mark, event in stream: File "/usr/local/lib/python2.7/dist- packages/genshi/filters/transform.py", line 1101, in __call__ for mark, event in stream: File "/usr/local/lib/python2.7/dist- packages/genshi/filters/transform.py", line 118, in __iter__ event = self.stream.next() File "/usr/local/lib/python2.7/dist- packages/genshi/filters/transform.py", line 734, in __call__ for mark, event in stream: File "/usr/local/lib/python2.7/dist- packages/genshi/filters/transform.py", line 702, in _mark for event in stream: File "/usr/local/lib/python2.7/dist-packages/genshi/template/base.py", line 618, in _include for event in stream: File "/usr/local/lib/python2.7/dist-packages/genshi/template/markup.py", line 378, in _match ctxt, start=idx + 1, **vars): File "/usr/local/lib/python2.7/dist-packages/genshi/template/markup.py", line 378, in _match ctxt, start=idx + 1, **vars): File "/usr/local/lib/python2.7/dist-packages/genshi/template/markup.py", line 362, in _match content = list(content) File "/usr/local/lib/python2.7/dist-packages/genshi/template/base.py", line 618, in _include for event in stream: File "/usr/local/lib/python2.7/dist-packages/genshi/template/markup.py", line 326, in _match for event in stream: File "/usr/local/lib/python2.7/dist-packages/genshi/template/markup.py", line 315, in _strip event = next() File "/usr/local/lib/python2.7/dist-packages/genshi/template/base.py", line 558, in _flatten for kind, data, pos in stream: File "/usr/local/lib/python2.7/dist-packages/genshi/core.py", line 289, in _ensure for event in stream: File "/usr/local/lib/python2.7/dist-packages/genshi/path.py", line 588, in _generate subevent = next() File "/usr/local/lib/python2.7/dist-packages/genshi/template/base.py", line 618, in _include for event in stream: File "/usr/local/lib/python2.7/dist-packages/genshi/template/markup.py", line 315, in _strip event = next() File "/usr/local/lib/python2.7/dist-packages/genshi/template/base.py", line 558, in _flatten for kind, data, pos in stream: File "/usr/local/lib/python2.7/dist-packages/genshi/core.py", line 289, in _ensure for event in stream: File "/usr/local/lib/python2.7/dist-packages/genshi/path.py", line 588, in _generate subevent = next() File "/usr/local/lib/python2.7/dist-packages/genshi/template/base.py", line 618, in _include for event in stream: File "/usr/local/lib/python2.7/dist-packages/genshi/template/markup.py", line 315, in _strip event = next() File "/usr/local/lib/python2.7/dist-packages/genshi/template/base.py", line 558, in _flatten for kind, data, pos in stream: File "/usr/local/lib/python2.7/dist-packages/genshi/filters/i18n.py", line 178, in _generate for event in msgbuf.translate(gettext(msgbuf.format())): File "/usr/local/lib/python2.7/dist-packages/genshi/filters/i18n.py", line 1051, in translate events = self.events[order].pop(0) IndexError: pop from empty list }}} -- Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/10927> GHC <http://www.haskell.org/ghc/> The Glasgow Haskell Compiler

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[GHC] #13835: ghci with ":set +t" should print type before starting evaluation
by GHC 08 Aug '18

08 Aug '18

#13835: ghci with ":set +t" should print type before starting evaluation -------------------------------------+------------------------------------- Reporter: j.waldmann | Owner: (none) Type: feature | Status: new request | Priority: normal | Milestone: Component: GHCi | Version: 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: -------------------------------------+------------------------------------- Not an actual bug, but questionable design perhaps. I think this is backwards, as static analysis comes before evaluation, not after: {{{ Prelude> :set +t Prelude> reverse [True] [True] it :: [Bool] }}} When evaluation raises an exception, no type is printed. {{{ Prelude> :set +t Prelude> True && undefined *** Exception: Prelude.undefined CallStack (from HasCallStack): error, called at libraries/base/GHC/Err.hs:79:14 in base:GHC.Err undefined, called at <interactive>:8:9 in interactive:Ghci4 }}} For teaching (and for my own sanity) I'd much prefer output in logical succession. -- Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/13835> GHC <http://www.haskell.org/ghc/> The Glasgow Haskell Compiler

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[GHC] #12421: TestEquality and TestCoercion documentation is confusing
by GHC 07 Aug '18

07 Aug '18

#12421: TestEquality and TestCoercion documentation is confusing -------------------------------------+------------------------------------- Reporter: dfeuer | Owner: Type: bug | Status: new Priority: normal | Milestone: 8.0.2 Component: Core | Version: 8.0.1 Libraries | Keywords: | Operating System: Unknown/Multiple Architecture: | Type of failure: Documentation Unknown/Multiple | bug Test Case: | Blocked By: Blocking: | Related Tickets: Differential Rev(s): | Wiki Page: -------------------------------------+------------------------------------- Currently, the documentation for the `TestEquality` class indicates > This class contains types where you can learn the equality of two types from information contained in terms. Typically, only singleton types should inhabit this class. The `TestCoercion` documentation includes a similar caution about singleton types. But this is far too conservative! Length-indexed vectors can be made valid instances of `TestEquality` and `TestCoercion` in exactly one way: {{{#!hs data Nat = Z | S Nat data Vec a n where Nil :: Vec a 'Z Cons :: a -> Vec a n -> Vec a ('S n) instance TestEquality (Vec a) where testEquality Nil Nil = Just Refl testEquality (Cons _ xs) (Cons _ ys) = fmap (\Refl -> Refl) (testEquality xs ys) testEquality _ _ = Nothing instance TestCoercion (Vec a) where testCoercion xs ys = fmap (\Refl -> Coercion) (testEquality xs ys) }}} Polykinded heterogeneous lists are another nice non-singleton example for which each class has a single "most reasonable" instance: {{{#!hs data HList (f :: k -> *) (xs :: [k]) where HNil :: HList f '[] HCons :: f a -> HList f as -> HList f (a ': as) instance TestEquality f => TestEquality (HList f) where testEquality HNil HNil = Just Refl testEquality (HCons x xs) (HCons y ys) = do Refl <- testEquality x y Refl <- testEquality xs ys Just Refl testEquality _ _ = Nothing instance TestCoercion f => TestCoercion (HList f) where testCoercion HNil HNil = Just Coercion testCoercion (HCons x xs) (HCons y ys) = do Coercion <- testCoercion x y Coercion <- testCoercion xs ys Just Coercion testCoercion _ _ = Nothing }}} I don't know just how far the warning should be weakened; it may make sense to go as far as saying the type should generally be a GADT. -- Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/12421> GHC <http://www.haskell.org/ghc/> The Glasgow Haskell Compiler

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[GHC] #10599: Template Haskell doesn't allow `newName "type"`
by GHC 07 Aug '18

07 Aug '18

#10599: Template Haskell doesn't allow `newName "type"` -------------------------------------+------------------------------------- Reporter: meteficha | Owner: Type: bug | Status: new Priority: normal | Milestone: Component: Template | Version: 7.10.1 Haskell | Operating System: Unknown/Multiple Keywords: | Type of failure: None/Unknown Architecture: | Blocked By: Unknown/Multiple | Related Tickets: Test Case: | Blocking: | Differential Revisions: | -------------------------------------+------------------------------------- Using `type` as a name is, of course, forbidden. OTOH, `type_1` is allowed as a name. However, using GHC 7.10.1 and `ghc --make T.hs` on files: {{{#!hs -- T.hs {-# LANGUAGE TemplateHaskell #-} module T where import Q test -- Q.hs module Q where import Language.Haskell.TH test :: Q [Dec] test = do t <- newName "type" return [FunD t [Clause [] (NormalB $ LitE $ CharL 't') []]] }}} Leads to the following error: {{{ $ ghc --make -ddump-splices T.hs [2 of 2] Compiling T ( T.hs, T.o ) T.hs:6:1: Illegal variable name: ‘type’ When splicing a TH declaration: ident_0 type_1 = type_1 }}} The above example works fine for GHC 7.8.4, so it's a regression. Reference: https://github.com/yesodweb/persistent/issues/412 -- Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/10599> GHC <http://www.haskell.org/ghc/> The Glasgow Haskell Compiler

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[GHC] #13137: Dynamic linker not initialised.
by GHC 07 Aug '18

07 Aug '18

#13137: Dynamic linker not initialised. ----------------------------------------+--------------------------------- Reporter: djduke | Owner: Type: bug | Status: new Priority: normal | Milestone: Component: Compiler | Version: 8.0.2 Keywords: | Operating System: MacOS X Architecture: Unknown/Multiple | Type of failure: None/Unknown Test Case: | Blocked By: Blocking: | Related Tickets: Differential Rev(s): | Wiki Page: ----------------------------------------+--------------------------------- Attempting to build accelerate-llvm-1.0.0.0 cloned from the repo at https://github.com/AccelerateHS/accelerate-llvm, using: OSX 10.12.2 (Sierra) GHC 8.0.2 Command line tools for Xcode 8.2.1 [25 of 52] Compiling Data.Range.Range ( Data/Range/Range.hs, dist/build/Data/Range/Range.o ) (GHC version 8.0.2 for x86_64-apple-darwin): Dynamic linker not initialised Please report this as a GHC bug: http://www.haskell.org/ghc/reportabug [26 of 52] Compiling Data.Array.Accelerate.LLVM.Util ( Data/Array/Accelerate/LLVM/Util.hs, dist/build/Data/Array/Accelerate/LLVM/Util.o ) <no location info>: error: <command line>: can't load .so/.DLL for: /Users/scsdjd/Library/Haskell/ghc-8.0.2-x86_64/lib/x86_64-osx-ghc-8.0.2 /libHSllvm-general-3.8.0.0-KHGbcTTSuxFL0az0gf3S53-ghc8.0.2.dylib (dlopen(/Users/scsdjd/Library/Haskell/ghc-8.0.2-x86_64/lib/x86_64-osx- ghc-8.0.2/libHSllvm-general-3.8.0.0-KHGbcTTSuxFL0az0gf3S53-ghc8.0.2.dylib, 5): Symbol not found: __ZTIN4llvm11InstructionE Referenced from: /Users/scsdjd/Library/Haskell/ghc-8.0.2-x86_64/lib/x86_64-osx-ghc-8.0.2 /libHSllvm-general-3.8.0.0-KHGbcTTSuxFL0az0gf3S53-ghc8.0.2.dylib Expected in: flat namespace in /Users/scsdjd/Library/Haskell/ghc-8.0.2-x86_64/lib/x86_64-osx- ghc-8.0.2/libHSllvm-general-3.8.0.0-KHGbcTTSuxFL0az0gf3S53-ghc8.0.2.dylib) [27 of 52] Compiling Data.Array.Accelerate.LLVM.CodeGen.Ptr ( Data/Array/Accelerate/LLVM/CodeGen/Ptr.hs, dist/build/Data/Array/Accelerate/LLVM/CodeGen/Ptr.o ) <no location info>: error: ghc: panic! (the 'impossible' happened) (GHC version 8.0.2 for x86_64-apple-darwin): Dynamic linker not initialised Please report this as a GHC bug: http://www.haskell.org/ghc/reportabug ... so I have. I note previous tickets for "Dynamic linker not initialised", but not clear they are relevant due to different OS etc. -- Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/13137> GHC <http://www.haskell.org/ghc/> The Glasgow Haskell Compiler

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[GHC] #10355: Dynamic linker not initialised
by GHC 07 Aug '18

07 Aug '18

#10355: Dynamic linker not initialised -------------------------------------+------------------------------------- Reporter: dpiponi | 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 | Blocked By: Test Case: | Related Tickets: Blocking: | Differential Revisions: | -------------------------------------+------------------------------------- I get this message: [ 3 of 24] Compiling Cable ( src/Cable.hs, dist/build/ui/ui- tmp/Cable.o ) <no location info>: ghc: panic! (the 'impossible' happened) (GHC version 7.10.1 for x86_64-apple-darwin): Dynamic linker not initialised Please report this as a GHC bug: http://www.haskell.org/ghc/reportabug when building my code here: https://github.com/dpiponi/Moodler/tree/master/Moodler/src under Yosemite 10.10.2 So I'm reporting it. -- Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/10355> GHC <http://www.haskell.org/ghc/> The Glasgow Haskell Compiler

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[GHC] #13607: Panic with profiled compiler: Dynamic linker not initialised
by GHC 07 Aug '18

07 Aug '18

#13607: Panic with profiled compiler: Dynamic linker not initialised -------------------------------------+------------------------------------- Reporter: RyanGlScott | Owner: (none) Type: bug | Status: new Priority: normal | Milestone: Component: Compiler | Version: 8.1 Keywords: | Operating System: Unknown/Multiple Architecture: | Type of failure: Compile-time Unknown/Multiple | crash or panic Test Case: | Blocked By: Blocking: | Related Tickets: Differential Rev(s): | Wiki Page: -------------------------------------+------------------------------------- There are several Trac tickets floating around which mention this panic, including: * #9868 (ghc: panic! Dynamic linker not initialised) * #10355 (Dynamic linker not initialised) * #10919 (ghc: panic! (the 'impossible' happened) ... Dynamic linker not initialised) * #13137 (Dynamic linker not initialised.) * #13531 (GHC fails with "Dynamic linker not initialised" when -j is on and trying to load nonexistent .so file) However, none seem particularly simple to reproduce. I have a (marginally) easier way to trigger this panic. You'll need the following: * A copy of GHC HEAD built with the `prof` flavor. For reference, I am using GHC HEAD built against 1f4fd37efac4795493677d5df81c83d22eac5f74. * A single package built with `cabal-install`. For simplicity, I used `random`: {{{ $ cabal install random-1.1 -w ~/Software/ghc3/inplace/bin/ghc-stage2 }}} Once it's installed, you'll need to learn `random`'s package ID, which can be done with `ghc-pkg`. For instance: {{{ 3$ ~/Software/ghc3/inplace/bin/ghc-pkg describe random name: random version: 1.1 id: random-1.1-Gnn89iTXDuaz90MEyLmyr ... }}} * You'll need these three Haskell files: {{{#!hs -- Foo.hs {-# LANGUAGE TemplateHaskell #-} module Foo where import Language.Haskell.TH foo :: Bool foo = $(conE 'True) }}} {{{#!hs -- Foo2.hs {-# LANGUAGE TemplateHaskell #-} module Foo2 where import Language.Haskell.TH foo2 = $(conE 'False) }}} {{{#!hs -- Bar.hs module Bar where import Foo import Foo2 bar :: () bar = foo `seq` foo2 `seq` () }}} Once you have all of these, you can trigger the bug by invoking GHC like so: {{{ $ ~/Software/ghc3/inplace/bin/ghc-stage2 -fforce-recomp Bar.hs -j2 -package-id random-1.1-Gnn89iTXDuaz90MEyLmyr [1 of 3] Compiling Foo ( Foo.hs, Foo.o ) <no location info>: error: <command line>: can't load .so/.DLL for: libHSrandom-1.1-Gnn89iTXDuaz90MEyLmyr.so (libHSrandom-1.1-Gnn89iTXDuaz90MEyLmyr.so: cannot open shared object file: No such file or directory) [2 of 3] Compiling Foo2 ( Foo2.hs, Foo2.o ) <no location info>: error: ghc-stage2: panic! (the 'impossible' happened) (GHC version 8.3.20170423 for x86_64-unknown-linux): Dynamic linker not initialised CallStack (from -prof): Linker.CAF (<entire-module>) Please report this as a GHC bug: http://www.haskell.org/ghc/reportabug }}} In case it's important, this is using 64-bit Linux. cc'ing angerman, who requested an easier way to reproduce this panic in https://ghc.haskell.org/trac/ghc/ticket/13137#comment:6. -- Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/13607> GHC <http://www.haskell.org/ghc/> The Glasgow Haskell Compiler

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[GHC] #9868: ghc: panic! Dynamic linker not initialised
by GHC 07 Aug '18

07 Aug '18

#9868: ghc: panic! Dynamic linker not initialised -------------------------------------+------------------------------------- Reporter: Jamedjo | Owner: Type: bug | Status: new Priority: normal | Milestone: Component: Compiler | Version: 7.8.3 Keywords: | Operating System: MacOS X Architecture: x86_64 (amd64) | Type of failure: Compile- Difficulty: Unknown | time crash Blocked By: | Test Case: Related Tickets: | Blocking: | Differential Revisions: -------------------------------------+------------------------------------- I was playing around and not expecting cabal build to succeed yet. If if didn't say the impossible had happened I would assumed I was missing something and used the error to drive my next action {{{ <no location info>: ghc: panic! (the 'impossible' happened) (GHC version 7.8.3 for x86_64-apple-darwin): Dynamic linker not initialised Please report this as a GHC bug: http://www.haskell.org/ghc/reportabug }}} There had been another error before: {{{ <no location info>: <command line>: can't load .so/.DLL for: /Users/JamesEJ/bindings- cef3/dist/build/libHSbindings-cef3-0.1.0-ghc7.8.3.dylib (dlopen(/Users/JamesEJ/bindings-cef3/dist/build/libHSbindings- cef3-0.1.0-ghc7.8.3.dylib, 9): Symbol not found: _cef_add_cross_origin_whitelist_entry Referenced from: /Users/JamesEJ/bindings-cef3/dist/build/libHSbindings- cef3-0.1.0-ghc7.8.3.dylib Expected in: flat namespace in /Users/JamesEJ/bindings-cef3/dist/build/libHSbindings- cef3-0.1.0-ghc7.8.3.dylib) }}} -- Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/9868> GHC <http://www.haskell.org/ghc/> The Glasgow Haskell Compiler

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