Yea, I know what the author intended :).  However, no one other than the
author ever used it that way, afaik.

On Tue, Sep 1, 2015 at 8:41 PM nathan binkert <[email protected]> wrote:

> The author of breakpoint did intend it to be a noop that would cause a
> trap in gdb. :)  Setting a breakpoint from gdb isn't always easy.
> Sometimes you need to have very specific conditions to make things happen
> that are hard to code in gdb.
>
> That said, it's not necessary to ignore sigtrap since you can just ask GDB
> to ignore the signal and not deliver it to the process.
>
>   Nate
>
> On Tue, Sep 1, 2015 at 9:09 AM, Steve Reinhardt <[email protected]> wrote:
>
>>
>>
>> > On Aug. 28, 2015, 6:50 a.m., Andreas Sandberg wrote:
>> > > I think this makes sense, but I think this might breaks some of the
>> assumptions of the Debug::breakpoint() call. This call seems to be
>> sprinkled across NSGigE and Sinic devices. It seems like the author of
>> those devices assumed that Debug::breakpoint() would be a no-op if a
>> debugger isn't connected. Do we need to get rid of those calls before this
>> change goes in? Or is the assumption that those devices are broken and no
>> longer in use?
>>
>> Good catch... I hadn't noticed that.  There are a few calls outside of
>> those two devices as well: there's a debugbreak pseudo-inst, a
>> BreakPCEvent, and some pretty idiosyncratic usage in base/statistics.cc and
>> arch/alpha/ev5.cc.
>>
>> My inclination is to get rid of all the unprotected calls, but leave the
>> ones that require some intention on the part of the user (the pseudo-inst
>> and the BreakPCEvent).  I'd also consider getting rid of the kill() call in
>> Debug::breakpoint and requiring the user to manually set a breakpoint there
>> from gdb (you could even put it in your .gdbinit) if we're concerned about
>> things like the pseudo-inst inadvertently killing the process, but I'd like
>> to know whether that's actually an issue before we make that change.
>>
>>
>> - Steve
>>
>
>>
>> -----------------------------------------------------------
>
>
>> This is an automatically generated e-mail. To reply, visit:
>>
> http://reviews.gem5.org/r/3074/#review7068
>> -----------------------------------------------------------
>>
>>
>> On Aug. 23, 2015, 11:55 p.m., Steve Reinhardt wrote:
>> >
>> > -----------------------------------------------------------
>
>
>> > This is an automatically generated e-mail. To reply, visit:
>> > http://reviews.gem5.org/r/3074/
>>
> > -----------------------------------------------------------
>> >
>> > (Updated Aug. 23, 2015, 11:55 p.m.)
>> >
>> >
>> > Review request for Default.
>> >
>> >
>> > Repository: gem5
>> >
>> >
>> > Description
>> > -------
>>
>
>> >
>> > Changeset 11062:fbce13fdad11
>> > ---------------------------
>> > sim: don't ignore SIG_TRAP
>> >
>> > By ignoring SIG_TRAP, using --debug-break <N> when not connected to
>> > a debugger becomes a no-op.  Apparently this was intended to be a
>> > feature, though the rationale is not clear.
>> >
>> > If we don't ignore SIG_TRAP, then using --debug-break <N> when not
>> > connected to a debugger causes the simulation process to terminate
>> > at tick N.  This is occasionally useful, e.g., if you just want to
>> > collect a trace for a specific window of execution then you can combine
>> > this with --debug-start to do exactly that.
>> >
>> >
>> > Diffs
>>
> > -----
>> >
>> >   src/sim/init_signals.cc 842f56345a421244a7a8988a5bc4fb1cfbf409ef
>> >
>> > Diff: http://reviews.gem5.org/r/3074/diff/
>> >
>> >
>> > Testing
>> > -------
>> >
>> >
>> > Thanks,
>> >
>> > Steve Reinhardt
>> >
>> >
>>
>> _______________________________________________
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>>
>
>
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