Re: [RFA] set/show enable-software-singlestep

[Daniel Jacobowitz <drow at false dot org>]

On Wed, Jun 25, 2008 at 08:54:24AM -0400, Joel Brobecker wrote:
> Hi Michael,
> 
> > 2008-06-23  Michael Snyder  <msnyder@specifix.com>
> > 
> > 	* infrun.c (can_use_sw_ss): New mode variable.
> > 	(show_can_use_sw_ss): New setshow helper function.
> > 	(resume): Check for can-use-software-singlestep.
> > 	(_initialize_infrun): Add set/show command for 
> > 	can-use-software-singlestep.
> 
> As discussed previously on gdb@, I think this is a useful feature
> even outside of reverse debugging.  Regarding Pedro's question
> about making this feature transparent, that would be tough for
> the example I gave, which is Tru64 - we want to be able to use
> s/w single-step only on programs that use threads. To make it automatic,
> we'd have to reliably detect that a program uses threads. Perhaps
> this is doable, but having the option is an easy first step. Later
> on, we can always extend the option to a tri-state with an "auto"
> setting if it helps...

I think it should already be auto.  can-use-software-singlestep is
unintuitive - either do use it, don't use it, or use GDB's best
judgement.  And if the user selects to use it and it isn't supported,
that's an error when we next want to singlestep.  WDYT?

> The code itself looks good, but I'm not so sure about accessing this
> feature through a "maint" command. Since in my eyes it's a feature,
> I'd personally be inclined to make it accessible through  "set/show
> can-use-software-singlestep".  It is an obscure feature, however, so
> I'm not really that concerned about it. How about we wait for another
> week to see if we have any other comment; if not, then just commit
> as is.

I agree with Joel; if we want to have the user knob at all, no gain in
hiding it.

-- 
Daniel Jacobowitz
CodeSourcery