Regression with php7.0-igbinary

[mig5]

After upgrading php7.0-igbinary to 1.2.1-36a2d5b7-1dotdeb+8.1, we started getting a variety of errors in Drupal 7 sites 'unable to get a data value' and others. No errors from PHP specifically.

Oct 26 05:32:01 XXXXXX drupal: https://www.XXXXXXXX.XX|1477452721|rules|XX.XX.XX.XX|https://www.XXXXX.XX/XXXXX/XXXX-X?page=7||0||Unable to evaluate condition data_is.
Oct 26 05:32:01 XXXXXX drupal: https://www.XXXXXXXX.XX|1477452721|rules|XX.XX.XX.XX|https://www.XXXXX.XX/XXXXX/XXXXX-X?page=7||0||Unable to get a data value. Error: Invalid data value given. Be sure it matches the required data type and format.

We downgraded to 1.2.1-12b7c703-1dotdeb+8.2 and the issues have gone away.

Debian Jessie 8.6 running 7.0.12-1~dotdeb+8.1
amd64

What is curious is that in our routine 'apt-get upgrade', the only PHP package available for upgrade was this igbinary one... not sure when it entered the repository? Apparently since the last main PHP release?

Not sure how to troubleshoot this regression, since there are no other more usefu; segfaults or fatal exits, just errors at an application level..

Any advice appreciated. Thanks!