Several new directives were added. GLR grammars
now support locations. %token numbers can now be
hexadecimal integers. A POSIX conformant yacc
command and -ly library installation can now be
disabled at build. Numbers are no longer
arbitrarily limited to 16-bit counts. Semicolons
are now allowed before "|" in grammar rules, as
POSIX requires. Bison-generated parsers no longer
default to using the alloca function to extend the
parser stack. Furthermore, there have been
incompatible changes to error token location,
semicolon handling, and NUL byte and newline
handling.
