[Patch, Fortran] Add c_float128{,_complex} as GNU extension to ISO_C_BINDING

[Tobias Burnus]

*ping*
http://gcc.gnu.org/ml/fortran/2011-09/msg00150.html

On 09/28/2011 04:28 PM, Tobias Burnus wrote:
> This patch makes the GCC extension __float128 (_Complex) available in 
> the C bindings via C_FLOAT128 and C_FLOAT128_COMPLEX.
>
> Additionally, I have improved the diagnostic for explicitly use 
> associating -std= versioned symbols. And I have finally added the 
> iso*.def files to the makefile dependencies.
>
> As usual, with -std=f2008, the GNU extensions are not loaded. I have 
> also updated the documentation.
>
> OK for the trunk?
>
> Tobias
>
> PS: If you think that C_FLOAT128/C_FLOAT128_COMPLEX are bad names for 
> C's __float128, please speak up before gfortran - and other compilers 
> implement it. (At least one vendor is implementing __float128 support 
> and plans to modify ISO_C_BINDING.) The proper name would be 
> C___FLOAT128, but that looks awkward!