A solution that I used is to patch OCaml to read a configuration file at
startup. This configuration file overrides what was put in the config at
compile time, so that you can change what C compiler/assembler/linker
you use at every execution. It was done in a first attempt to build a
cross-compiling compiler. Then, you can provide a simple tool that tests
the environment and generate the corresponding configuration file.

--Fabrice

On 12/14/2011 04:49 PM, Adrien wrote:
> On 14/12/2011, Gerd Stolpmann <info@gerd-stolpmann.de> wrote:
>> Am Mittwoch, den 14.12.2011, 14:37 +0100 schrieb Adrien:
>>> On 14/12/2011, Alain Frisch <alain@frisch.fr> wrote:
>>>> As a concrete problem, until a few days ago, the mingw port could not be
>>>> used with recent versions of Cygwin without some small hacks (like
>>>> copying manually /bin/gcc-3.exe into gcc.exe, and passing more
>>>> directories to flexlink).  No big deal, but it can discourage beginners.
>>>
>>> Actually, I think that you should have used the "/etc/alternatives"
>>> symlinks: /usr/bin/gcc points to /etc/alternatives/FOO and you can make
>>> this
>>> FOO symlink point to the /usr/bin/BAR binary that you want.
>>
>> There are no (usable) symlinks in Windows. Cygwin includes an emulation,
>> but it is not understood by win32 programs, and hence this mechanism is
>> unavailable for ocamlc/opt and flexlink.
> 
> Hmmm, right. But if /usr/bin/gcc is already a symlink, ocaml wouldn't be
> able to use it at all... I find it quite weird but I don't have a cygwin box
> to test.
> 
> But windows actually has symlinks. Kind of. Starting with Vista and the
> corresponding NTFS version. But by default you need to be an administrator
> to use them, you can only create a limited number of symlink in a given
> folder afaiu, some functions work on the symlink and some on the target
> (stat()/lstat()). They have a number of limitations and last time I looked
> at them, I found them to be mostly unusable because of their limitations.
> 
> They're one quite big issue I've had for packages on windows: if I
> cross-compile a library from Linux, and make a tarball which has a number of
> symlink in it. What to do when untarring on windows? Try to create symlinks?
> Use hardlinks when possible? Copy the file's contents? Something else?
> 
> Regards,
> Adrien Nader
>