RFA/RFC: Adding support for gmp and mpfr sources in the build tree

[Nick Clifton]

Hi Paolo,

> Would you please take care of testing this patch, including both your 
> changes to the GMP testing mechanism and the required changes to the 
> templates?

Your patch worked perfectly after I made one small change:

> +host_modules= { module= gmp; lib_path=.libs; bootstrap=true;
> +	        host="none-${host_vendor}-${host_os}";
> +		target="none-${host_vendor}-${host_os}"; };

I had to change this to:

 > +host_modules= { module= gmp; lib_path=.libs; bootstrap=true;
 > +	        host="${host_alias}";
 > +		target="${host_alias}"; };

Otherwise I ended up with this slightly strange error message:

   ../gmp/.libs/libgmp.so: undefined reference to `__gmpn_add_nc'
   ../gmp/.libs/libgmp.so: undefined reference to `__gmpn_sub_nc'
   collect2: ld returned 1 exit status
   make[1]: *** [cc1-dummy] Error 1

This was on a 64-bit host, and I guess that GMP's configure mechanism 
was incorrectly guessing that it was running on some other kind of 
machine.  I found that I did not need to change the host and target 
definitions for the mpfr host module, so I left them alone.

Cheers
   Nick