Re: [PATCH] Use read_memory_unsigned_integer when reading to CORE_ADDR

[Klee Dienes <klee@apple.com>]

Perhaps something along the lines of the following?

{
   unsigned char buf[sizeof (CORE_ADDR)];
   if (target_read_memory (memaddr, buf, TYPE_LENGTH 
(builtin_type_void_data_ptr)) != 0)
	error ("Unable to determine lower bound of array.");
   *lower_bound = extract_typed_address (buf, 
builtin_type_void_data_ptr);
}

That's a bit verbose, and it's not clear to me if sizeof (CORE_ADDR) is 
guaranteed to be large enough to contain a raw target pointer, but I 
can't really think of any better alternatives.

Aside from the intimidating comments in findvar.c, this would seem a 
good candidate for extract_address ... though a similar modification 
would have to be made to it to handle the sign-extension as well.

Or alternately, I could just leave well-enough alone, and be careful to 
truncate CORE_ADDRs to 32 bits in our target xfer_memory code (or the 
MIPS code could sign-extend it in the same place).

On Saturday, October 5, 2002, at 10:57 PM, Daniel Jacobowitz wrote:
>
> Well, I'm a little concerned about this.  MIPS generally wants the
> result to be sign extended; the MIPS 32-bit ABIs map onto the lowest
> and highest 2G segments of the 64-bit address space, not the low 4G
> segment.  Isn't there an appropriate function somewhere to read a 
> CORE_ADDR?
>
> Answer: Yes, there is, but it has the same problem.  You're just
> extending current practice, so I don't see a problem with your patch.
>
> Andrew, is my understanding right?  Is there some reason this isn't a
> problem?