Re: failure of cross-compilation detection on BlueGene/L

[Christian Rössel]

Ralf Wildenhues schrieb:
> Hello Christian,
>
> sorry, I saw your mail only after sending my other.
>
> * Christian Rössel wrote on Sat, Jun 06, 2009 at 08:19:08AM CEST:
> > Note that we are working on some heuristics to detect supercomputer  
> > platforms like Blue Gene, Cray, NEC etc. that require cross compilation.  
> > This detection will be available as a macro soon and render it  
> > unnecessary that the user specifies --host and --build on the supported  
> > platforms.
>
> Unless those heuristics extend to other platforms as well, we will have
> at least a bit of a hard time accepting them into Autoconf proper (if
> that's what you're aiming for), because in the long run, even just
> enumerating all the cross compilation systems will be a burden for
> Autoconf.

Hi Ralf,

at the moment I'm just thinking of an external macro that sets $host if 
it is not set by the user. Depending on $cpu and $os of the build system 
you check for some special directories (e.g. /bgsys for Blue Gene/P). 
Usually todays supercomputers have such special and distinct 
directories. This is not the holy grail but works quite reliable for us. 
I think that these heuristics is not general and reliable enough to be 
included in autoconf/config.guess, therefore I'm thinking of providing a 
macro at http://www.nongnu.org/autoconf-archive/ e.g.

Cheers,
Christian