Hi,
I sent this question to haskell-cafe, realizing later that perhaps
this list is a better place for it.
Patrick
---------- Forwarded message ----------
From: Patrick LeBoutillier
Date: Fri, Dec 4, 2009 at 2:09 PM
Subject: FFI and ghci
To: Haskell Cafe
Hi all,
I have a small FFI-based library that I like to test like this:
$ ghci -I../c -L../c/.libs -lmlp t.hs
GHCi, version 6.10.1: http://www.haskell.org/ghc/ :? for help
Loading package ghc-prim ... linking ... done.
Loading package integer ... linking ... done.
Loading package base ... linking ... done.
Loading object (dynamic) mlp ... done
final link ... done
[1 of 9] Compiling MLP ( MLP.hs, interpreted )
[2 of 9] Compiling MLP.Error ( MLP/Error.hs, interpreted )
[3 of 9] Compiling MLP.Context ( MLP/Context.hs, interpreted )
[4 of 9] Compiling MLP.Runtime ( MLP/Runtime.hs, interpreted )
[5 of 9] Compiling MLP.Object ( MLP/Object.hs, interpreted )
[6 of 9] Compiling MLP.Type ( MLP/Type.hs, interpreted )
[7 of 9] Compiling MLP.Value ( MLP/Value.hs, interpreted )
[8 of 9] Compiling MLP.Language ( MLP/Language.hs, interpreted )
[9 of 9] Compiling Main ( t.hs, interpreted )
Ok, modules loaded: MLP, MLP.Object, Main, MLP.Runtime, MLP.Context,
MLP.Error, MLP.Value, MLP.Type, MLP.Language.
*Main> main
Note: Inside libmlp.so, another shared object is loaded using dlopen().
When running this test program I get some sporadic segmentation
faults, which seem to always occur at entrypoint to the
shared object that is loaded with dlopen().
But when I compile it with ghc, i.e.
$ ghc --make -I../c -L../c/.libs -lmlp t.hs
I can't reproduce crash.
Can anyone see why this could be happening? It's quite possible that
there is really a bug in the C code,
but if someone knows about a bug or something in ghci that can cause
this behaviour I can stop looking...
Thanks a lot,
Patrick
--
=====================
Patrick LeBoutillier
Rosemère, Québec, Canada
