Re: [RFA/PATCH] breakpoint.c: fix until command

[Andrew Cagney <ac131313@redhat.com>]

> Michael Snyder formulates:
> 
>> 1) Use find_pc_partial_function to determine bounds and
>> distinguish between in-bounds and out-of-bounds locations.
>> 2) For func_start > loc >= func_end, use a frame-relative bp.
>> 3) For func_start == loc or loc < func_start or loc > func_end,
>> use a frameless bp.

This doesn't work.  It hightlights why the edge condition can't be 
cleanly resolved.  You can't rely on ``func_start == loc'' as an 
identifier of this special case.  The prolog analysis / skip will just 
make the behavior confusing / conunter intitive and the doco really 
messy.  Look at the heated debate that occures with ``break foo'' vs 
``break *foo'' vs ``break lineof(foo)''.

Consider for instance:

	(gdb) break foo
	(gdb) c
	Break point foo reached
	(gdb) until foo

depending on the prolog analysis (and hence the architecture), this will 
behave differently.

I personally think the decision reached several months ago should stand 
- `until foo' behaves per the documentation.

We can then separatly persue a recursive centric version of the function 
vis:

- finish LOCATION
- rbreak
(set tempoary breakpoint at return address)

...

Andrew