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

[Jim Blandy <jimb at zwingli dot cygnus dot com>]

[Sorry, replying to several messages and repeating myself a bit.]

Andrew Cagney <ac131313@cygnus.com> writes:
> Any way, consider the intent of someone entering a sequence like:
> 
> 	(gdb) x/w foo
> 	0x0
> 	(gdb) x/i foo
> 	nop
> 	(gdb) print/x *(int*)foo
> 	0xdeadbeef
> 
> vs 
> (gdb) print/x *(int*)foo
> 	0x0
> 
> and where should this go:
> 
> 	(gdb) set *(int*)foo = 0xdeadbeef
> 
> This mysterious address switching strikes me as wierd.

This is an existing problem.  Any C compiler for a machine with distinct
code and data address spaces will do the same thing.

The value of the proposal Michael and I have put together is not that
it solves all possible problems, or that it makes counterintuitive
architectures somehow behave like more familiar architectures.  The
value is that it allows a user to accomplish what they want at all.

I think our proposal:
- adapts to other sorts of spaces well,
- has a consistent type story, and 
- doesn't change the meaning of any valid C expressions.