* data/c.m4 (b4_yy_symbol_print_generate):

(b4_yy_symbol_print_generate): Use 'YYSTYPE const' rather than
'const YYSTYPE', and similarly for YYLTYPE.  This fixes one
of the bugs reported today by Derek M Jones in
<http://lists.gnu.org/archive/html/bug-bison/2006-05/msg00027.html>.
* doc/bison.texinfo (Value Type): Document that YYSTYPE must be
defined to be a type name without parens or brackets.
(Location Type): Similarly for YYLTYPE.
* tests/regression.at (Trivial grammars): Put in a test for this
bug that will be caught by 'make maintainer-check' (though not,
alas, by 'make check' unless your compiler is picky).