On Wed, Apr 27, 2011 at 10:03 AM, Jan Hubicka <hubi...@ucw.cz> wrote:
>> >> - else if (entry->checksum != checksum)
>> >> + else if (entry->lineno_checksum != lineno_checksum
>> >> + || entry->cfg_checksum != cfg_checksum)
>> >> {
>> >> error ("coverage mismatch for function %u while reading
>> >> execution counters",
>> >> fn_ident);
>> >> - error ("checksum is %x instead of %x", entry->checksum,
>> >> checksum);
>> >> + error ("checksum is (%x,%x) instead of (%x,%x)",
>> >> + entry->lineno_checksum, entry->cfg_checksum,
>> >> + lineno_checksum, cfg_checksum);
>> >
>> > Can't we give more informative message whether code changes or it seems to
>> > be
>> > optimization options disprepancy?
>>
>> Good idea -- but to change the warning not the error here. For the
>> warning (which is promoted to error by default) currently it is:
>>
>> error: coverage mismatch for function xxxx while reading counter yyy.
>> note: control flow checksum is aaa instead of bbb
>>
>> Could be:
>> error: function xxx's control flow does match its profile data (counter yyy).
>> note: use -Wno-error=coverage-mismatch to tolerate the mismatch but
>> performance may drop if the function is hot.
>
> Well, I had more in mind giving diffent message for lineno checksum
> difference than cfg checksum.
> But I agree that we probably don't want to output checksum numbers, those are
> useless even for debugging.
> Probably could follow same warning/error rules as the main loading routine
> whatever you converged
> to.
>
Sure.
Thanks,
David
> Honza
>
