Re: Auto removing BPs on stop

[Fabian Cenedese <Cenedese@indel.ch>]

>> Whenever the target stops gdb will remove all breakpoints from the target
>> and set them again before stepping/continuing. What functionality in gdb
>> depends on this? Backtrace? Breakpoint handling?
>> In our multitasking system a thread can stop on a breakpoint while the
>> others are still running, so the breakpoints are still useful and shouldn't
>> be removed.
>
>GDB can't cope with this.  GDB assumes that when it is told that the
>inferior has "stopped", its state will not change, and all threads can
>be examined.

I know, that's the biggest obstacle in generally using gdb as debugger.
So far we had our own debugger which "just" used gdb for symbol lookups
and PC<->source resultions. I guess I need to stay that way for some
(long) time.

>> What would break in gdb if I just removed those calls to unset/re-set
>> the breakpoints? I know that the setting is partly necessary as new
>> breakpoints aren't yet set.
>
>I don't know.  A lot of places may still read target memory without
>using the routines that "remove" breakpoints from GDB's image of target
>memory, for one thing; this is slowly being fixed.
>
>My goal is to stop the needless removing and reinserting some day, but
>I don't think it will work yet.

I hoped I could at least move the breakpoint/single-step stuff from our
debugger to gdb as the routines in gdb are more advanced. I'll try
some more...

Thanks

bye  Fabi