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

Hi Steve,

I have read the commit you are referring to and here are my thoughts:

Changing the value of the LO_MARKER_A/B will not cause an ABI breakage, however as the values "leak out" from lo_send, then the markers can not be found as the old values are used instead. I believe this confirms what you are observing.

The commit is 4 years old so I am surprised it did not cause problems in previous releases.

Now, when I read the code, I wonder if the change to the marker values was really needed, but I remember using those values fixed a bug. I have to dig into the list emails to see if I said something about it when I sent the patch. 

--
Cam


On 24 juil. 2013, at 17:22, 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
> 
> ------------------------------------------------------------------------------
> See everything from the browser to the database with AppDynamics
> Get end-to-end visibility with application monitoring from AppDynamics
> Isolate bottlenecks and diagnose root cause in seconds.
> Start your free trial of AppDynamics Pro today!
> http://pubads.g.doubleclick.net/gampad/clk?id=48808831&iu=/4140/ostg.clktrk
> _______________________________________________
> liblo-devel mailing list
> lib...@li...
> https://lists.sourceforge.net/lists/listinfo/liblo-devel