[antlr-interest] ANTLR version compatibility

[Kin-Hong Wong]

Hi all,

Our current Java product uses ANTLR v3.0 with generated lexer and parser.
Recently we have a requirement to integrate with a third-party library
which depends on ANTLR v3.1.3 runtime. We found that the our v3.0-generated
lexers and parsers were not compatible with ANTLR 3.1.3 runtime. We are
prepared to upgrade to newer version of ANTLR. Should we upgrade to v3.1.3
or v3.4 (the latest)? if we upgrade to v3.4, will the third-party library
be compatible to v3.4 runtime?

In general, are lexers/parsers generated by a previous version of ANTLR
compatible with newer version of ANTLR runtime? Is there information that
state such backward compatibility (I couldn't find any in ANTLR release
notes).

Thanks,
Kin-Hong