darcs 2.8 fails to compile with ghc 7.6
Ganesh Sittampalam reports the following failure when building darcs 2.8 with ghc 7.6 RC1:
ghc.exe: panic! (the 'impossible' happened)
(GHC version 7.6.0.20120822 for i386-unknown-mingw32):
ds_ev_term
cobox{v a6Aho} [lid] `cast`
(<main:Darcs.Test.Patch.WithState.WithState{tc r1oms}
model{tv t4H} [tv]
(main:Darcs.Witnesses.Ordered.FL{tc
r1iNn} prim{tv t4D} [tv]
main:Darcs.Witnesses.Ordered.:>{tc
r1iNy} main:Darcs.Witnesses.Ordered.FL{tc r1iNn}
prim{tv t4D} [tv])>
ghc-prim:GHC.Types.~{(w) tc 31Q}
main:Darcs.Test.Patch.WithState.WithState{tc r1oms}
(Sym
cobox{v a6AgE} [lid])
<main:Darcs.Witnesses.Ordered.FL{tc r1iNn}
prim{tv t4D} [tv]
main:Darcs.Witnesses.Ordered.:>{tc r1iNy}
main:Darcs.Witnesses.Ordered.FL{tc r1iNn}
prim{tv t4D} [tv]>)
(let {EvBinds{cobox{v a6zY5} [lid]
= cobox{v a6Aho} [lid] `cast`
(<main:Darcs.Test.Patch.WithState.WithState{tc r1oms}
model{tv t4H} [tv]
(main:Darcs.Witnesses.Ordered.FL{tc r1iNn}
prim{tv t4D} [tv]
main:Darcs.Witnesses.Ordered.:>{tc r1iNy}
main:Darcs.Witnesses.Ordered.FL{tc r1iNn}
prim{tv t4D} [tv])>
ghc-prim:GHC.Types.~{(w) tc 31Q}
main:Darcs.Test.Patch.WithState.WithState{tc r1oms}
(Sym
cobox{v a6AgE} [lid])
<main:Darcs.Witnesses.Ordered.FL{tc r1iNn}
prim{tv t4D} [tv]
main:Darcs.Witnesses.Ordered.:>{tc r1iNy}
main:Darcs.Witnesses.Ordered.FL{tc r1iNn}
prim{tv t4D} [tv]>)
cobox{v a6zY6} [lid] = CO <t{tv a6zY1} [tv]>}}
cobox{v a6zY5} [lid] <xx{tv a6zY3} [sk]> <yy{tv a6zY4} [sk]>
-> <t{tv a6zY1} [tv]>)Project + dependencies can be found at http://urchin.earth.li/\~ganesh/temp/tcproblem.tar.bz2 (run build.sh).
Trac metadata
| Trac field | Value |
|---|---|
| Version | 7.6.1-rc1 |
| Type | Bug |
| TypeOfFailure | OtherFailure |
| Priority | high |
| Resolution | Unresolved |
| Component | Compiler |
| Test case | |
| Differential revisions | |
| BlockedBy | |
| Related | |
| Blocking | |
| CC | |
| Operating system | |
| Architecture |