Re: [RFC] Display exact entered expression for watchpoints

[Duncan Roe <duncanr@optimation.com.au>]

Hi Pierre,

I like the "0x" variant better also.

Just a BTW, but in the circumstances you describe, I would do:

  watch *(struct ui_file **) 0x823b5cc

so that gdb knows how many bytes to watch. 

E.g.:

Hardware watchpoint 2: *(double *) 3221223348

Old value = 3.2999999999999994
New value = 3.2999999999999998

i.e. a 1-bit change in the 8th byte (0x400a666666666665 -> 0x400a666666666666)

Cheers ... Duncan.

On Thu, Nov 14, 2002 at 12:00:18PM +0100, Pierre Muller wrote:
>  When I watch a memory location,
> I almost always use hexadecimal notation.
> 
> For instance lets say that I want to watch 
> the memory containing the value of gdb_stderr
> On my linux box 
> (top-gdb)p &gdb_stderr
> returns
> $1 = (struct ui_file **) 0x823b5cc
> (ok, here I could simply use 'watch gdb_stderr,
> but in some other cases like dynamically allocated memory I can't).
> if I enter
> (top-gdb) watch *0x823b5cc
> Hardware watchpoint 3: *136558028
> (top-gdb) inf b
> Num Type           Disp Enb Address    What
> 1   breakpoint     keep y   0x080f0d79 in internal_error
>                                        at ../../src/origdb/utils.c:810
> 2   breakpoint     keep y   0x080783eb in info_command
>                                        at ../../src/origdb/cli/cli-cmds.c:202
>         silent
>         return
> 3   hw watchpoint  keep y              *136558028
> (top-gdb)
> 
> 
> After my patch, I get
> (top-gdb) watch *0x823b5cc
> Hardware watchpoint 3: *0x823b5cc
> (top-gdb) inf b
> Num Type           Disp Enb Address    What
> 1   breakpoint     keep y   0x080f0d79 in internal_error
>                                        at ../../src/origdb/utils.c:810
> 2   breakpoint     keep y   0x080783eb in info_command
>                                        at ../../src/origdb/cli/cli-cmds.c:202
>         silent
>         return
> 3   hw watchpoint  keep y              *0x823b5cc
>