Re: fix math wrt volatile-bitfields vs C++ model

[Bernd Edlinger <bernd dot edlinger at hotmail dot de>]

Hi,


On Tue, 17 Jun 2014 10:08:33, Richard Biener wrote:
> On Tue, Jun 17, 2014 at 4:08 AM, DJ Delorie <dj@redhat.com> wrote:
>>
>>> Looks ok to me, but can you add a testcase please?
>>
>> I have a testcase, but if -flto the testcase doesn't include *any*
>> definition of the test function, just all the LTO data.  Is this
>> normal?
> 
> Without -ffat-lto-objects yes, this is normal.  If you are trying to
> do a scan-assembler or so then this will be difficult with LTO.
> If LTO is not necessary to trigger the bug and you just want to
> use the torture I suggest to dg-skip-if -flto.
> 
>>> Also check if 4.9 is affected.
>>
>> It is...  same fix works, though.
> 
> Thanks,
> Richard.


If you have a test case where the generated code is actually different
with and without your patch, that would be interesting.

Please see gcc.dg/pr23623.c and gcc.dg/pr56997-4.c
for examples how to automatically scan the intermediate code which is
generated by -fdump-rtl-final to check the expected access mode.
That should work for all targets, even if they have different assembler
syntax.


Thanks
Bernd.