+2011-01-29 Joel E. Denny <joeldenny@joeldenny.org>
+
+ Do not allow identifiers that start with a dash.
+ This cleans up our previous fixes for a bug whereby Bison
+ discarded `.field' in `$-1.field'. The previous fixes were less
+ restrictive about where a dash could appear in an identifier, but
+ the restrictions were hard to explain. That bug was reported and
+ this final fix was originally suggested by Paul Hilfinger. This
+ also fixes a remaining bug reported by Paul Eggert whereby Bison
+ parses `%token ID -123' as `%token ID - 123' and handles `-' as an
+ identifier. Now, `-' cannot be an identifier. Discussed in
+ threads beginning at
+ <http://lists.gnu.org/archive/html/bug-bison/2011-01/msg00000.html>,
+ <http://lists.gnu.org/archive/html/bug-bison/2011-01/msg00004.html>.
+ * NEWS (2.5): Update entry describing the dash extension to
+ grammar symbol names. Also, move that entry before the named
+ references entry because the latter mentions the former.
+ * doc/bison.texinfo (Symbol): Update documentation for symbol
+ names. As suggested by Paul Eggert, mention the effect of periods
+ and dashes on named references.
+ (Decl Summary): Update documentation for unquoted %define values,
+ which, as a side effect, can no longer start with dashes either.
+ * src/scan-code.l (id): Implement.
+ * src/scan-gram.l (id): Implement.
+ * tests/actions.at (Exotic Dollars): Extend test group to exercise
+ bug reported by Paul Hilfinger.
+ * tests/input.at (Symbols): Update test group, and extend to
+ exercise bug reported by Paul Eggert.
+ * tests/named-refs.at (Stray symbols in brackets): Update test
+ group.
+ ($ or @ followed by . or -): Likewise.
+ * tests/regression.at (Invalid inputs): Likewise.
+
2011-01-24 Joel E. Denny <joeldenny@joeldenny.org>
* data/yacc.c: Fix last apostrophe warning from xgettext.