On Wed, 09 Jul 2014 17:31:21 +0200, Jan Kratochvil wrote:
> On Wed, 09 Jul 2014 13:52:00 +0200, Pedro Alves wrote:
> > On 07/09/2014 11:33 AM, Jan Kratochvil wrote:
> > > --- a/gdb/value.c
> > > +++ b/gdb/value.c
> > > @@ -198,12 +198,13 @@ struct value
> > >    unsigned int lazy : 1;
> > >  
> > >    /* If nonzero, this is the value of a variable that does not
> > > -     actually exist in the program.  If nonzero, and LVAL is
> > > +     actually fully exist in the program.  If nonzero, and LVAL is
> > >       lval_register, this is a register ($pc, $sp, etc., never a
> > >       program variable) that has not been saved in the frame.  All
> > >       optimized-out values are treated pretty much the same, except
> > >       registers have a different string representation and related
> > > -     error strings.  */
> > > +     error strings.  It is true also for only partially optimized
> > > +     out variables - see the 'unavailable' field below.  */
> > >    unsigned int optimized_out : 1;
> > >  
> > >    /* If value is a variable, is it initialized or not.  */
> > > @@ -334,7 +335,10 @@ struct value
> > >       valid if lazy is nonzero.  */
> > >    gdb_byte *contents;
> > >  
> > > -  /* Unavailable ranges in CONTENTS.  We mark unavailable ranges,
> > > +  /* If OPTIMIZED_OUT is false then UNAVAILABLE must be VEC_empty
> > > +     (not necessarily NULL).  
> > 
> > Hmm, why?  We can collect only part of a non-optimized out value.
> > What am I missing?
> 
> I miss some documentation how these availability fields interact together.

From a comment in mail
	Message-Id: <201102071427.55970.pedro@codesourcery.com>
	We give preference to printing <optimized out> rather
	than <unavailable>, since if a value had been optimized out
	at compile time, it can never be collected at run-time.

it seems it is just reversed, that 'unavailable' can exist only for
!optimized_out and it cannot exist for for optimized_out values.


> You are right, this patch regresses during gdbserver mode.

It PASSes now even in gdbserver mode.


Thanks,
Jan