Re: [RFC/RFA] gdb extension for Harvard architectures

[Andrew Cagney <ac131313 at cygnus dot com>]

>> To the best of my knowledge, ISO C says nothing about cast operations 
>> that convert between code and data pointers.  What we do have is a 
>> certain level of accepted behavour.  For instance on a unified byte 
>> addressable address space architecture things like:
>> 
>> sizeof(void*) == sizeof((*)())
>> ((*)()) (void*) foo == ((*)()) foo
>> 
>> However, on a harvard address space architecture we have none of that.
> 
> 
> Right.  We don't.  What's your point?

Compilers, such as GCC implement:

	int *i = &func;

based on the assumption that sizeof(i) == sizeof(&func) - that is the 
operation is a simple copy.

I think it is reasonable to expect that one day there will be targets 
that have sizeof(i) < sizeof(&func) (or vice versa) which would then 
make the above totally meaningless - the value would be truncated during 
the transfer.

Andrew