[GHC] #9009: Confusing error message when loading package with TH

[GHC]

#9009: Confusing error message when loading package with TH
-------------------------------------+-------------------------------------
              Reporter:  jstolarek   |            Owner:
                  Type:  bug         |           Status:  infoneeded
              Priority:  normal      |        Milestone:
             Component:  Package     |          Version:  7.8.2
  system                             |         Keywords:
            Resolution:              |     Architecture:  Unknown/Multiple
      Operating System:              |       Difficulty:  Unknown
  Unknown/Multiple                   |       Blocked By:
       Type of failure:  Other       |  Related Tickets:
             Test Case:              |
              Blocking:              |
Differential Revisions:              |
-------------------------------------+-------------------------------------

Comment (by thomie):

 This is still not reproducable for me with 7.8.3 (I get the same error
 from comment:3). I am using the haskell-platform 2014.02 in the global
 database, an initially empty user database (deleted ~/.ghc and ~/.cabal)
 and no sandbox.

 But it I did reproduce it with a recent HEAD. I followed the steps from
 comment:2 and also removed the `MINIMAL` pragma from
 src/Data/Singletons/Prelude/Ord.hs in `singletons-1.0`.

 {{{
 $ uname -a
 Linux feng-laptop 3.13.0-39-generic #66-Ubuntu SMP Tue Oct 28 13:30:27 UTC
 2014 x86_64 x86_64 x86_64 GNU/Linux

 $ /opt/ghc/head/bin/ghc-pkg list
 /opt/ghc/head/lib/ghc-7.9.20141108/package.conf.d
    Cabal-1.21.1.0
    array-0.5.0.1
    base-4.8.0.0
    bin-package-db-0.0.0.0
    binary-0.7.1.0
    bytestring-0.10.4.0
    containers-0.5.5.1
    deepseq-1.3.0.3
    directory-1.2.1.1
    filepath-1.3.0.3
    ghc-7.9.20141108
    ghc-prim-0.3.1.0
    haskeline-0.7.1.3
    haskell2010-1.1.2.1
    haskell98-2.0.0.4
    hoopl-3.10.0.2
    hpc-0.6.0.2
    integer-gmp-0.5.1.0
    old-locale-1.0.0.7
    old-time-1.1.0.3
    pretty-1.1.1.1
    process-1.2.0.1
    rts-1.0
    template-haskell-2.10.0.0
    terminfo-0.4.0.0
    time-1.5
    transformers-0.4.1.0
    unix-2.7.0.2
    xhtml-3000.2.1
 /home/thomas/.ghc/x86_64-linux-7.9.20141108/package.conf.d
    mtl-2.2.1
    singletons-1.0
    syb-0.4.2
    th-desugar-1.4.2

 $ /opt/ghc/head/bin/ghc-7.9.20141108 Foo.hs
 [1 of 1] Compiling Foo              ( Foo.hs, Foo.o )
 <command line>: can't load .so/.DLL for: /home/thomas/.cabal/lib/x86_64
 -linux-
 ghc-7.9.20141108/singletons-1.0/libHSsingl_LteS7xqJUFW9l0IV1AW3w0-ghc7.9.20141108.so
 (/home/thomas/.cabal/lib/x86_64-linux-
 ghc-7.9.20141108/singletons-1.0/libHSsingl_LteS7xqJUFW9l0IV1AW3w0-ghc7.9.20141108.so:
 undefined symbol:
 singlzuLteS7xqJUFW9l0IV1AW3w0_DataziSingletonsziSingleziMonad_wrapUnSingFun5_closure)
 }}}

--
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/9009#comment:5>
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