Re: [RFA] string_to_core_addr fix

[Kevin Buettner <kevinb at redhat dot com>]

On Oct 10,  3:07pm, Martin M. Hunt wrote:

> This is necessary for 64-bit targets where sometimes 32-bit
> values must be sign-extended to 64-bits.
> 
> 2002-10-10  Martin M. Hunt  <hunt@redhat.com>
> 
> 	* utils.c (string_to_core_addr): After turning string into
> 	a number, convert to a CORE_ADDR using POINTER_TO_ADDRESS
> 	which will do necessary sign-extension, etc.
>
> Index: utils.c
> ===================================================================
> RCS file: /cvs/src/src/gdb/utils.c,v
> retrieving revision 1.80
> diff -u -p -r1.80 utils.c
> --- utils.c	20 Sep 2002 00:24:01 -0000	1.80
> +++ utils.c	10 Oct 2002 22:06:50 -0000
> @@ -2649,7 +2649,7 @@ string_to_core_addr (const char *my_stri
>  	    internal_error (__FILE__, __LINE__, "invalid decimal");
>  	}
>      }
> -  return addr;
> +  return POINTER_TO_ADDRESS (builtin_type_void_data_ptr, &addr); 
>  }
>  
>  char *

While I agree that something like this is needed, I'm not convinced that
using POINTER_TO_ADDRESS on a CORE_ADDR is right.  By default,
unsigned_pointer_to_address() is used.  It looks like this:

    /* Given a pointer of type TYPE in target form in BUF, return the
       address it represents.  */
    CORE_ADDR
    unsigned_pointer_to_address (struct type *type, void *buf)
    {
      return extract_address (buf, TYPE_LENGTH (type));
    }

The problem is that ``addr'' is an address in host format (i.e, a CORE_ADDR),
not a target address.  I suspect you'll get incorrect results if the
host and target are of different endianness or if sizeof (CORE_ADDR) !=
TYPE_LENGTH (type).

I think you could get the right results by writing addr to a buffer
(maybe using store_typed_address) and then using extract_typed_address(),
but there may be a more straightforward way to do it.

Kevin