Is the FreeBSD ABI compatibility policy documented anywhere

Dag-Erling Smørgrav des at
Sat Oct 10 17:11:53 UTC 2009

"Simon L. Nielsen" <simon at> writes:
> It's not entirely that simple.  The ABI on a stable branch like 7.x
> should be backward compatible, but there isn't a guarantee of forward
> compatibility.  IE, 7.0 binary should be able to run on 7.x, but a 7.2
> binary might not run on 7.0.  It should be more or less the same with
> the API's.
> PS. do note that there is no 100% guarantee.

Correct, but we're getting closer to that now that we have symbol
versioning - although we won't reach 100% until we have versioned
symbols in *all* libraries, which is currently not the case.  Even then,
a developer might break the ABI by mistake, but hopefully we'd catch
that before it made it into a release.

Dag-Erling Smørgrav - des at

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