[PATCH 4/8] Add support for testing __STDC_WANT_IEC_60559_TYPES_EXT__

[Joseph Myers]

On Wed, 9 Nov 2016, Gabriel F. T. Gomes wrote:

> This will also implicitly enforce a minimum GCC 4.9.  Given
> the standard is a C11 derivative, it would seem reasonable
> to assume a C11 compiler with _Generic support.  This allows
> for much simpler type classification macros which in theory
> should be supported on any C11 compiler.

I don't think that's appropriate.  The aim should be to minimize the 
number of conditionals (on versions, supported types, etc.) in the 
individual headers with type-generic macros, at the expense of more 
complexity somewhere defining infrastructure for such macros.

Also, __USE_ISOC11 relates purely to library facilities.  It says nothing 
about availability of language support.

-- 
Joseph S. Myers
joseph@codesourcery.com