Re: Reductions during Bison error handling

[Richard Stallman]

    A program relying on an unsupported Bison feature, perhaps undocumented,
    discovered by trial and error or reading the sources or whatever, and
    breaks when Bison is updated must expect to be rewritten.

For some programs, that policy is acceptable.  The nature of the job
Bison does requires a more cautious policy, as I explained before.  I
expect the Bison maintainers to give compatibility a very high
priority.