ghc - force library search order

[John Lask]

I hav a module that depends upon (binds to) the microsoft uuid.lib 
(libuuid.a) this is a static library which exports some labels such as 
IID_IPersistFile. I was playing around with trying to get it to work both 
with normal compiling via ghc and to dynamically load in ghci. As we know, 
ghci can't load static libraries and so was not able to resolve the linkage. 
I therefore decided to directly incorporate the objects of (libuuid.a) into 
the haskell .a and ghci .o file (ghci) . To do this I needed to 
ject   --whole-archive libuuid.a --no-whole-archive (or alternatively the 
list of objects) into the link command at an appropriate point to enable the 
resolution of the linkage.

I have achieved my goal but only by constructing the list of objects to link 
entirely manually, constructing both the .a and .o for the haskell library 
manually. I am not satisfied with this solution as it is fragile wrt changes 
in the module structure of the library I have constructed.

jvl

----- Original Message ----- 
From: "Simon Marlow" <marlowsd at gmail.com>
To: "John Lask" <jvlask at hotmail.com>
Cc: <glasgow-haskell-users at haskell.org>
Sent: Monday, June 01, 2009 9:15 PM
Subject: Re: ghc - force library search order


> On 29/05/2009 15:19, John Lask wrote:
>>
>> ----- Original Message ----- From: "Duncan Coutts"
>> <duncan.coutts at worc.ox.ac.uk>
>> To: "John Lask" <jvlask at hotmail.com>
>> Sent: Friday, May 29, 2009 8:09 PM
>> Subject: Re: [Haskell-cafe] ghc - force library search order
>>
>>
>>> On Fri, 2009-05-29 at 18:08 +1000, John Lask wrote:
>>>> I need to force a library to be searched for unresolved symbols after
>>>> all
>>>> other libraries have been searched, and I would rather not resort to
>>>> constructing the linker command line directly. Is there a way to do
>>>> this?
>>>>
>>>> i.e. I want for example -lfoo to appear after all other haskell
>>>> libraries
>>>> and before system libraries (for example -lmsvcrt) once ghc has
>>>> constructed
>>>> the link command. i.e. how is it possible to coerce ghc into respecting
>>>> dependencies between the libraries. GHC does a good job in general with
>>>> native libraries, but there are allways corner cases.
>>>>
>>>> I have a feeling this is not possible, but it dosn't hurt to ask.
>
> No, there's currently no way to inject flags that come *after* the linker 
> flags for the packages on the linker command line.
>
> It might help if you describe at a higher level what it is you're trying 
> to do.  There might be a better way to achieve it.
>
> Cheers,
> Simon
>