[GHC] #9036: ghc: panic! (the 'impossible' happened) (Binder's type (SingI Symbol <a String>) /= RHS type (String))
#9036: ghc: panic! (the 'impossible' happened) (Binder's type (SingI Symbol <a
String>) /= RHS type (String))
--------------------------------+---------------------------------------
Reporter: ntc2 | Owner:
Type: bug | Status: new
Priority: normal | Milestone:
Component: Compiler | Version: 7.6.3
Keywords: GHC.TypeLits | Operating System: Linux
Architecture: x86 | Type of failure: Compile-time crash
Difficulty: Unknown | Test Case:
Blocked By: | Blocking:
Related Tickets: |
--------------------------------+---------------------------------------
Compilation error message:
{{{
ghc: panic! (the 'impossible' happened)
(GHC version 7.6.3 for i386-unknown-linux):
cgLookupPanic (probably invalid Core; try -dcore-lint)
cobox{v a212} [lid]
static binds for:
local binds for:
main:Debug.Trace.LogTree.Test.$p1AllShow{v r1pg} [gid[ClassOp]]
main:Debug.Trace.LogTree.Test.$p2AllShow{v r1ph} [gid[ClassOp]]
main:Debug.Trace.LogTree.Test.$p3AllShow{v r1pi} [gid[ClassOp]]
main:Debug.Trace.LogTree.Test.$p4AllShow{v r1pj} [gid[ClassOp]]
main:Debug.Trace.LogTree.Test.$p5AllShow{v r1pk} [gid[ClassOp]]
main:Debug.Trace.LogTree.Test.$p6AllShow{v r1pl} [gid[ClassOp]]
Please report this as a GHC bug: http://www.haskell.org/ghc/reportabug
}}}
Error in -dcore-lint:
{{{
[10 of 10] Compiling Debug.Trace.LogTree.Test (
src/Debug/Trace/LogTree/Test.hs, tmp/Debug/Trace/LogTree/Test.o )
*** Core Lint errors : in result of Desugar (after optimization) ***
{-# LINE 122 "src/Debug/Trace/LogTree/Test.hs #-}: Warning:
[RHS of $dSingI_a20r :: GHC.TypeLits.SingI GHC.TypeLits.Symbol "h"]
The type of this binder doesn't match the type of its RHS:
$dSingI_a20r
Binder's type: GHC.TypeLits.SingI GHC.TypeLits.Symbol "h"
Rhs type: [GHC.Types.Char]
}}}
So, it looks like it's related to !TypeLits. The full -dcore-lint output
is attached.
To reproduce:
1. git clone https://github.com/ntc2/haskell-call-trace.git
2. cd haskell-call-trace
3. git checkout break-ghc
3.
#9036: ghc: panic! Binder's type (SingI Symbol <a String>) /= RHS type (String)
---------------------------------------+--------------------------------
Reporter: ntc2 | Owner:
Type: bug | Status: new
Priority: normal | Milestone:
Component: Compiler | Version: 7.6.3
Resolution: | Keywords: GHC.TypeLits
Operating System: Linux | Architecture: x86
Type of failure: Compile-time crash | Difficulty: Unknown
Test Case: | Blocked By:
Blocking: | Related Tickets:
---------------------------------------+--------------------------------
--
Ticket URL:
#9036: ghc: panic! Binder's type (SingI Symbol <a String>) /= RHS type (String)
---------------------------------------+--------------------------------
Reporter: ntc2 | Owner:
Type: bug | Status: new
Priority: normal | Milestone:
Component: Compiler | Version: 7.6.3
Resolution: | Keywords: GHC.TypeLits
Operating System: Linux | Architecture: x86
Type of failure: Compile-time crash | Difficulty: Unknown
Test Case: | Blocked By:
Blocking: | Related Tickets:
---------------------------------------+--------------------------------
Comment (by ntc2):
The wiki won't let me attach the -dcore-lint output because it's too big
(it's about half a MB).
--
Ticket URL:
#9036: ghc: panic! Binder's type (SingI Symbol <a String>) /= RHS type (String)
---------------------------------------+--------------------------------
Reporter: ntc2 | Owner:
Type: bug | Status: closed
Priority: normal | Milestone:
Component: Compiler | Version: 7.6.3
Resolution: fixed | Keywords: GHC.TypeLits
Operating System: Linux | Architecture: x86
Type of failure: Compile-time crash | Difficulty: Unknown
Test Case: | Blocked By:
Blocking: | Related Tickets:
---------------------------------------+--------------------------------
Changes (by monoidal):
* status: new => closed
* resolution: => fixed
Comment:
I reduced your program to a single file
{{{
{-# LANGUAGE MultiParamTypeClasses #-}
{-# LANGUAGE TypeOperators #-}
{-# LANGUAGE TypeFamilies #-}
module Debug.Trace.LogTree.Test where
class UncurryM t where
type GetMonad t :: * -> *
class Curry a b where
type Curried a b :: *
gSimple :: String -> String -> [String]
gSimple = simpleLogger (return ())
simpleLogger :: Maybe (GetMonad t after) -> t `Curried` [t]
simpleLogger _ _ = undefined
}}}
which compiled with -O gives the same error in 7.6.3 but 7.8.2 gives a
typecheck error. I believe this is another instance of bugs #7729, #8142,
#8227. So, the issue is fixed in 7.8 and since 7.6 is not actively
developed, I'm closing the ticket.
--
Ticket URL:
#9036: ghc: panic! Binder's type (SingI Symbol <a String>) /= RHS type (String)
-------------------------------------------------+-------------------------
Reporter: ntc2 | Owner:
Type: bug | Status:
Priority: normal | closed
Component: Compiler | Milestone:
Resolution: fixed | Version: 7.6.3
Operating System: Linux | Keywords:
Type of failure: Compile-time crash | GHC.TypeLits
Test Case: | Architecture: x86
indexed_types/should_compile/T9036 | Difficulty:
Blocking: | Unknown
| Blocked By:
| Related Tickets:
-------------------------------------------------+-------------------------
Changes (by simonpj):
* testcase: => indexed_types/should_compile/T9036
Comment:
Great. I've added the small example as a regression test, just in case.
Simon
--
Ticket URL:
#9036: ghc: panic! Binder's type (SingI Symbol <a String>) /= RHS type (String)
-------------------------------------------------+-------------------------
Reporter: ntc2 | Owner:
Type: bug | Status:
Priority: normal | closed
Component: Compiler | Milestone:
Resolution: fixed | Version: 7.6.3
Operating System: Linux | Keywords:
Type of failure: Compile-time crash | GHC.TypeLits
Test Case: | Architecture: x86
indexed_types/should_compile/T9036 | Difficulty:
Blocking: | Unknown
| Blocked By:
| Related Tickets:
-------------------------------------------------+-------------------------
Comment (by Simon Peyton Jones
participants (1)
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