Re: [Haskell-cafe] OSX, ghci, dylib, what is the correct way?

On Tue, Jun 14, 2011 at 4:26 AM, Simon Marlow wrote:

On 12/06/2011 20:17, Jason Dagit wrote:

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On Sun, Jun 12, 2011 at 11:45 AM, Brandon Allbery  wrote:

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On Sun, Jun 12, 2011 at 14:31, Jason Dagit  wrote:

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If I build the C library as a .a, then ghci comlains that it cannot open the .dylib.  My first question is: Why does ghci need a .dylib and does it really use it?

Static libraries are... static.  ghci would have to rebuild itself against the static archive to use it; that's how static archives work.  Dynamic libraries are dynamic because they can be loaded at runtime instead of compile time.

Interesting.  When I use dtruss to see what files ghci opens, it definitely opens .a files.  That gave me the impression it knows how to open a .a and use it at run-time.

GHC as of version 7.0 can load .a files into GHCi.

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When I build a dylib I get a [segfault when loading the code into ghci][2].

I don't know what the cause of that is - when you load a .dylib into GHCi, the normal system dynamic linker is used.

How would you track it down? I'd really like to fix this and I don't mind debugging it, but I've tried all the things I could think of (valgrind, dtruss, gdb and printf). Valgrind didn't help because ghci couldn't read from stdin. gdb isn't so great because I was missing debug symbols for everything. I don't really believe it is an error in the RTS or the library code so it seems like gdb won't ever help here. Ideas? Thanks, Jason