How does compatibility work between different erts versions?

[zabrane]

Hi All,
Can i load a module compiled with erts-8.3.5.7 inside a (old) VM running erts-8.1?
How compatibility works between different erts versions?
Finally, how one can deduce the Erlang version number from erts version number?
Thanks.

[rickard]

@zabrane

Can i load a module compiled with erts-8.3.5.7 inside a (old) VM running erts-8.1?
How compatibility works between different erts versions?

It should be ok since those erts versions are from the same OTP release (OTP 19). An exception could be if there would have been a need to fix a bug that for example introduced a new instruction between those versions. I don’t think that have ever happened, though. (@bjorng ?)

This page describes things regarding compatibility.

@zabrane

Finally, how one can deduce the Erlang version number from erts version number?

If you manually want to look up OTP version(s) for an application version you can search on the OTP Versions Tree page which is automatically updated when we release patches.

If you want to automate this process you can parse the otp_versions.table file in the top directory on the master branch on github. It is also automatically updated when we release patches.

[bjorng]

@rickard

An exception could be if there would have been a need to fix a bug that for example introduced a new instruction between those versions. I don’t think that have ever happened, though. (@bjorng ?)

As far as I can remember, it has never happened.

[zabrane]

Thanks guys