I maintain the bindings for the R programming language. One test that reads p12 files started failing because the order in which the CA list is returned is now reverse from what it was in openssl 1.1.1.

I think the actual change of behavior is in sk_X509_value() which now returns cert indexed from the front instead of the back.

Is this an intended change? Here is the the p12 file that we use for unit tests: https://github.com/jeroen/openssl/blob/master/tests/google.dk/wildcard-google.dk-chain.p12?raw=true
If needed I can try to extract a C example.