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

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

Andrew Cagney <ac131313@cygnus.com> writes:
> > Andrew Cagney <ac131313@cygnus.com> writes:
> > 
> >> With regard to a @data->@io pointer.  That is probably wrong.  Pointers, 
> >> which are typically implemented as address registers (not to be confused 
> >> with GDB's core addr), have a fixed size for a given address space.
> > 
> > 
> > Not sure what you mean here.  A value of type `@io foo *' is perfectly
> > meaningful.  Its size depends on characteristics of the I/O space.
> 
> What about ``@io int *@code''?  The pointer's size is independant (well 
> at least for the moment) of the source address space.  Hence the 
> attribute attached to the pointer (instead of pointee) adds nothing.

The declaration

        @io int * @code x;

would declare a variable x in code space that points to an int in io
space.  Of course, GDB doesn't do declarations.

For casts, sure; the latter qualifier in `(@io int * @code) 0x10' is
meaningless.  Address space qualifiers are meaningless applied to
rvalues, as are `const' and `volatile'.  In `(int * const) x', the
`const' is meaningless, too, because the result of a cast expression
isn't an lvalue.

What's your point?