wide function pointer type

[Florian Weimer]

* Martin Uecker:

>> I don't expect a lot of uptake for this.  One problem is the suggested
>> aggregate representation of wide function pointers.  It's not exactly
>> common for non-C implementations to implement those aspects of the
>> platform C ABI.  
>
> Can you explain what you mean by this?  Usually non-C
> implementations build on C ABI, so if the C ABI is
> extended the extension is then available to them.

In practice, the shared ABI is just a subset of what is required for
full C.  Often, support for pass-by-value struct and union arguments and
return values are missing or implemented incorrectly (not according to
the platform ABI).  Other traditionally incomplete parts (relative to
C90) are variadic functions and bitfields.

Thanks,
Florian