making naked attr generally available

[Joern Rennecke]

> I think it would be good to allow architecture specific "interrupt" functions
> too. i.e. :
> 
> save all regs used (leaf functions), or _all_ regs (non-leaf)
> use appropriate RETI insn in epilogue.

Why would you want it to save call-saved registers that are not used in the
interrupt function?  Any called function should save these registers if it
uses them.

FWIW the #pragma interrput of the SH port only affects saving of call-used
registers.