corbett@okeeffe.Berkeley.EDU (Robert Corbett) (01/21/91)
I have placed a new version of Berkeley Yacc in ~ftp/pub/byacc.tar.Z
on ucbarpa (IP address 128.32.130.11). The new version fixes an
incompatibility with AT&T Yacc regarding precedence declarations.
The charateristic of grammars where the incompatibility makes a
difference is that a shift and more than one reduction must be
possible for a given state-lookahead pair and there must be a
precedence declaration for the lookahead symbol.
The incompatibility affects useful grammars. In particular, a version
of EQN produced using earlier versions of Berkeley Yacc will produce
different results from a version produced using AT&T Yacc.
Version 1.8 does not include improvements I previously said would be
in 1.8. I have deferred those changes until version 1.9. Version 1.8
contains only bug fixes (as was also the case for version 1.7).
Yours truly,
Bob Corbett
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