[darcs-devel] [issue836] darcs-2.0.0 build failure with ghc-6.8.2 on OS X 10.5.2

[Gregory Wright]

New submission from Gregory Wright <gwright at antiope.com>:

[originally posted to darcs-users; reposted to the bugs list.]

Hi,

I've experienced an odd build failure of darcs-2.0.0 on OS X (10.5.2)   
with
ghc 6.8.2.  The hardware is a MacBook Pro (2.6 GHz Intel, 4 GB RAM).

Running

$ ./configure
$ make

gives a successful build.  But

$ ./configure --with-docs
$ make

fails with

[ghc] src/Darcs/Patch/Read.o
[ghc] src/Darcs/Patch/Non.o
[ghc] src/Darcs/Patch/Real.o

src/Darcs/Patch/Real.lhs:100:26:
     GADT pattern match in non-rigid context for `NilRL'
       Tell GHC HQ if you'd like this to unify the context
     In the pattern: NilRL
     In the pattern: Just NilRL
     In a case alternative:
         Just NilRL
           -> ((\ imp_funny_name
                    -> imp_funny_name
                         ("src/Darcs/Patch/Real.lhs", 100, "15:47:58",
"Apr 30 2008"))
                 _bug)
                "found no patches in mergeUnravelled"

src/Darcs/Patch/Real.lhs:116:27:
     GADT pattern match in non-rigid context for `NilFL'
       Tell GHC HQ if you'd like this to unify the context
     In the pattern: NilFL
     In a case alternative: NilFL -> Just p
     In the expression:
         case sort_coalesceFL $ effect p of
           NilFL -> Just p
           _ -> Nothing

src/Darcs/Patch/Real.lhs:135:32:
     GADT pattern match in non-rigid context for `NilFL'
       Tell GHC HQ if you'd like this to unify the context
     In the pattern: NilFL
     In a case alternative: NilFL -> Just (NilFL, mapFL_FL Normal xs)
     In the expression:
         case sort_coalesceFL $ effect goneby of
           NilFL -> Just (NilFL, mapFL_FL Normal xs)
           _z -> Nothing

src/Darcs/Patch/Real.lhs:257:26:
     GADT pattern match in non-rigid context for `NilRL'
       Tell GHC HQ if you'd like this to unify the context
     In the pattern: NilRL
     In a case alternative: NilRL -> []
     In the expression:
         case reverseFL $ xx2patches ix xx of
           NilRL -> []
           Normal q :<: qs -> [Non (reverseRL qs) q]
           _ -> []

src/Darcs/Patch/Real.lhs:371:82:
     deps  not in scope because it has a wobbly type (solution: add a
type annotation)
     In the first argument of `reverseRL', namely `deps'
     In the first argument of `Non', namely `(reverseRL deps)'
     In the expression: Non (reverseRL deps) pp

src/Darcs/Patch/Real.lhs:428:50:
     GADT pattern match in non-rigid context for `NilFL'
       Tell GHC HQ if you'd like this to unify the context
     In the pattern: NilFL
     In a pattern guard for
        a case alternative:
         NilFL <- sort_coalesceFL $ effect c
     In a case alternative:
         ([], NilFL, Non c y)
           | NilFL <- sort_coalesceFL $ effect c
           -> Just (Normal y :> Conflictor a1'nop2 (y :>: NilFL) p2)
make: *** [src/Darcs/Patch/Real.o] Error 1

However, if I disable type witnesses, everything is fine.  So

$ ./configure --with-docs --without-type-witnesses
$ make

succeeds.

I can understand that type witnesses are new enough to possibly cause
problems on some platforms, but I'm baffled by the interaction with "-- 
with-docs".
Shouldn't "--with-docs" just cause the documentation to be built, and
not change any other build settings?

Best Wishes,
Greg

----------
messages: 4529
nosy: beschmi, dagit, gwright, tommy
status: unread
title: darcs-2.0.0 build failure with ghc-6.8.2 on OS X 10.5.2

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