Re: [liblo] lo_send argument markers broke 64-bit ABI compatibility

Okay, now I'm confused.

I made a mistake in the previous mail.  In fact SooperLooper does NOT
emit the error message when run against 0.26.  Additionally,

* It does NOT emit it when run against the version prior to 9adc42b1112.
* It DOES emit it when run against 9adc42b1112.
* It DOES emit it on current master.
* And it still DOES emit it on current master if I change the
LO_MARKER_A/B values back to how they were prior to 9adc42b1112.

This is different from the Ardour results, and I should note that this
completely breaks the SooperLooper GUI.  Something is going on here,
I'll continue to investigate.

Steve


On Wed, Jul 24, 2013 at 5:34 PM, Stephen Sinclair <rad...@gm...> wrote:
> I'll note that otherwise, it seems that Ardour can receive OSC
> messages, and apparently responds to incoming instructions without
> problem.  I can't see how to get it to send OSC messages however.
> (Though obviously something is sent on start-up, since I see that
> error message.)
>
> I tested SooperLooper as well, and seem to get "mismatching types and
> data" in both conditions.  However, I *also* get this messages when
> running against the Ubuntu version of liblo (0.26), so maybe there is
> some other issue.
>
> I will try a few more results from "apt-cache rdepends liblo7" to see
> if more problems show up.
>
> Steve
>
>
> On Wed, Jul 24, 2013 at 5:22 PM, Stephen Sinclair <rad...@gm...> wrote:
>> Hi list,
>>
>> So I finally located an actual ABI incompatibility due to 64-bit-ness
>> that was introduced post 0.26.
>>
>> In commit 9adc42b111, a bug in using the LO_MARKER_A/B scheme to check
>> for unmatched arguments at the end of the lo_send() call was changed
>> to fix problems with 64-bit.  The LO_MARKER_A/B constants were
>> extended to 64-bit values.
>>
>> Unfortunately, code that was not re-compiled against 0.27 that called
>> lo_send() broke after this change, since the LO_MARKER_A/B constants
>> are hard-coded into the calling code.  I have verified that swapping
>> out the liblo binary for 0.27 when running Ardour generates a message
>> "mismatching types and data".  Changing the LO_MARKERs back to their
>> previous values avoids this error message.
>>
>> Camille, do you recall whether this commit actually fixed a bug (as
>> noted in the commit comment), or was it just precautionary?  If the
>> latter, do you think it's safe to change it back?
>>
>> Steve