GHC-6.12.1: broken configure

[Ian Lynagh]

On Wed, Dec 23, 2009 at 09:49:40PM +0000, Simon Marlow wrote:
> On 22/12/09 12:59, Jens Petersen wrote:
>> 2009/12/19 Kirill A. Shutemov<kirill at shutemov.name>:
>>> I want to build ghc for i586-alt-linux-gnu.
>>
>> Why? :)
>>
>>> Why do not use config.guess to guess correct host/target/build
>>> instead of reinvent wheel?
>>
>> While I sympathize (I gave up long ago trying to use  host/target/build
>> with ghc - we use them by default in Fedora) - I guess the short answer
>> is something like cross-compiling is not supported or the effort
>> to support host/target/build is more than the win?  But those
>> are just my assumptions - I leave a real answer to a ghc buildsystem
>> expert.
>>
>> If you really want a fix searching trac and opening a ticket would be
>> more effective probably.
>
> I personally think we should revert to using the standard config.guess  
> and normalising the result as we used to.

I don't see the advantage. Before we had 484 lines of case expression in
configure.ac, which now and again needed tweaking to keep up with
changes in configure.

Now we don't need to be told the platform that we are building for, as
we just ask the bootstrapping compiler what platform it builds for, and
we only support building for that platform anyway. If you specify a
different platform then the build will break. I don't know if the
original poster means that he wants i586 as opposed to e.g. i386 (to
make use of newer instructions or to optimise differently), but if so we
don't do anything different for different subarches.

As far as I can see, the only reason we would need to support all the
platform values that configure supports is if/when we are going to
support cross-compilation.


Thanks
Ian