Re: [RFA] Add option to skip prologue in "break FILE:LINENO" (take 2)

[Michael Snyder <msnyder at specifix dot com>]

On Thu, 2008-01-10 at 09:24 -0800, Jim Blandy wrote:
> Joel Brobecker <brobecker at adacore.com> writes:
> > Following a request for comments regarding a proposed change of behavior
> > when inserting a breakpoint on a specific line number, we received a
> > variety of comments, and it appears very clearly that the proposal
> > was at the very least controversial.
> >
> > So, here is a new proposal where the existing behavior is preserved.
> > A new set/show command is introduced to allow the user to configure
> > GDB to activate the new proposed behavior:
> >
> >     (gdb) set/show breakpoint skip-prologue
> >
> > The help text for this command explains the purpose of this option:
> >
> >   Set the debugger behavior when inserting a breakpoint on a specific line.
> >   When inserting a breakpoint on a specific line number that corresponds
> >   to the prologue of a function, the debugger will automatically adjust
> >   its location to the first line past the prologue if this option is set.
> >
> > By default, this option is OFF, preserving the current behavior.
> > I think this should take care of all the objections I read so far.
> 
> Some of Michael's objections I didn't understand at all --- he seemed
> to believe that the change would affect GDB's behavior in ways I think
> it won't.  I don't think your change would affect the usage that was
> most important to him.
> 
> I'd like to get that (or perhaps just me) straightened out before we
> add an option.  Options of this sort are effective at resolving
> contentious mailing list threads, but not very effective for the vast
> majority of users.  Most users have little or no interest in GDB for
> its own sake, and won't look for options like 'set breakpoint
> skip-prologue', so subtle improvements that are disabled by default
> have almost no impact.

You're right -- initializations are treated as part of the function
body, not the prologue.  My concerns were largely unfounded.   ;-)