[darcs-users] ghci hints?

[Andrew Pimlott]

I've been struggling to load darcs modules into ghci.  After several
tries, I stumbled upon the ghci target in the makefile, but still no
luck:

    % make ghci
    ghci -cpp -package unix -package parsec -O -funbox-strict-fields -DHAVE_CURSES -package util -optl-lcurses -optl-lz -optl-lpthread darcs.lhs compat.o fpstring.o zlib_helper.o c_context.o
    warning: -O conflicts with --interactive; -O ignored.
       ___         ___ _
      / _ \ /\  /\/ __(_)
     / /_\// /_/ / /  | |      GHC Interactive, version 6.2.1, for Haskell 98.
    / /_\\/ __  / /___| |      http://www.haskell.org/ghc/
    \____/\/ /_/\____/|_|      Type :? for help.

    Loading package base ... linking ... done.
    Loading package lang ... linking ... done.
    Loading package concurrent ... linking ... done.
    Loading package QuickCheck ... linking ... done.
    Loading package readline ... linking ... done.
    Loading package unix ... linking ... done.
    Loading package posix ... linking ... done.
    Loading package util ... linking ... done.
    Loading package parsec ... linking ... done.
    Loading object (static) compat.o ... done
    Loading object (static) fpstring.o ... done
    Loading object (static) zlib_helper.o ... done
    Loading object (static) c_context.o ... done
    Loading object (dynamic) curses ... done
    Loading object (dynamic) z ... done
    Loading object (dynamic) pthread ... failed.
    Dynamic linker error message was:
       /usr/lib/libpthread.so: invalid ELF header
    Whilst trying to load:  (dynamic) pthread
    Directories to search are:
    ghc-6.2.1: user specified .o/.so/.DLL could not be loaded.
    make: *** [ghci] Error 1
    zsh: exit 2     make ghci

Probably a ghc bug.  I tried narrowing the command line, and got a
different problem:

    % ghci -cpp -package unix -package parsec -O -funbox-strict-fields -DHAVE_CURSES -package util -optl-lcurses -optl-lz compat.o fpstring.o  c_context.o         
    warning: -O conflicts with --interactive; -O ignored.
       ___         ___ _
      / _ \ /\  /\/ __(_)
     / /_\// /_/ / /  | |      GHC Interactive, version 6.2.1, for Haskell 98.
    / /_\\/ __  / /___| |      http://www.haskell.org/ghc/
    \____/\/ /_/\____/|_|      Type :? for help.

    Loading package base ... linking ... done.
    Loading package lang ... linking ... done.
    Loading package concurrent ... linking ... done.
    Loading package QuickCheck ... linking ... done.
    Loading package readline ... linking ... done.
    Loading package unix ... linking ... done.
    Loading package posix ... linking ... done.
    Loading package util ... linking ... done.
    Loading package parsec ... linking ... done.
    Loading object (static) compat.o ... done
    Loading object (static) fpstring.o ... done
    Loading object (static) c_context.o ... done
    Loading object (dynamic) curses ... done
    Loading object (dynamic) z ... done
    final link ... done
    Prelude> :load Printer
    Skipping  PatchMatchData   ( ./PatchMatchData.lhs, ./PatchMatchData.o )
    Skipping  DarcsFlags       ( ./DarcsFlags.lhs, ./DarcsFlags.o )
    Skipping  Exec             ( ./Exec.lhs, ./Exec.o )
    Skipping  Autoconf         ( ./Autoconf.lhs, ./Autoconf.o )
    Skipping  Workaround       ( ./Workaround.hs, ./Workaround.o )
    Skipping  DarcsUtils       ( ./DarcsUtils.lhs, ./DarcsUtils.o )
    Skipping  DarcsURL         ( ./DarcsURL.hs, ./DarcsURL.o )
    Skipping  SignalHandler    ( ./SignalHandler.lhs, ./SignalHandler.o )
    Skipping  FastPackedString ( ./FastPackedString.hs, ./FastPackedString.o )
    Skipping  Lock             ( ./Lock.lhs, ./Lock.o )
    Skipping  Curl             ( ./Curl.hs, ./Curl.o )
    Skipping  External         ( ./External.hs, ./External.o )
    Skipping  Printer          ( Printer.lhs, Printer.o )
    Ok, modules loaded: Printer, External, Curl, Lock, FastPackedString, SignalHandler, DarcsURL, DarcsUtils, Workaround, Autoconf, Exec, DarcsFlags, PatchMatchData.
    Prelude Printer> renderWith simplePrinters (text "abc") :: String
    Loading package haskell98 ... linking ... done.
    ./Lock.o: unknown symbol `__stginit_SignalHandler_'

Any idea what's causing that?  I get the same thing when I whittle the
command line down to

    ghci -cpp fpstring.o /usr/lib/libz.so compat.o

I'm using ghc 6.2.1 on Debian unstable.

Andrew