RE: [avr-libc-dev] Feature wishlisht

[Boyapati, Anitha]

>-----Original Message-----
>From: address@hidden
>[mailto:address@hidden On
>Behalf Of Joerg Wunsch
>Sent: Friday, February 25, 2011 11:38 PM
>To: address@hidden
>Subject: Re: [avr-libc-dev] Feature wishlisht
>
>As Boyapati, Anitha wrote:
>
>> I recently saw new/delete operator support being requested. This
>> made me think about C++ support. Likewise any such features in the
>> long run maybe...
>
>Yes, libstdc++ support is on the wishlist, even though it's beyond the
>scope of the avr-libc project.

Here comes my basic question - we do have libstdc++ in gcc already. However we 
are not building it for AVR-8 as of now. So what is the requirement for another 
library? To me it appears that libstdc++ can be built with a bootstrapped 
compiler (if it is possible).

>
>Likewise, 64-bit doubles are on the wishlist (as an option to the
>current implementation), but again, this is much of a compiler issue
>rather than library only.  My preference would be a compiler option
>much like we've got -mint8, so perhaps "-mdouble32" which enables the
>current behaviour, defaulting to double being 64 bits as this is what
>the ISO C standard asks for (well, sort of, but they're asking for
>*more* than 32-bit FP for the "double" datatype, and while 48 bits
>would satisfy their requirements, it's IMHO not possible to implement
>a 48-bit datatype in GCC).

This is still a mystery to me. When BITS_PER_UNIT/WORD is modified, the sizes 
of INT/LONG get affected. Implementing 48-bit double is definitely not straight 
forward (or may be not possible? To be confirmed)

Anitha