* data/c.m4 (yydestruct, yysymprint):

Use YYUSE instead of casting to void.
* data/glr.c (YYUSE): New macro.
(yyuserMerge, yyreportAmbiguity, yyreportSyntaxError):
Use it instead of rolling our own.
(YYLLOC_DEFAULT, YYCHK, YYDPRINTF, YY_SYMBOL_PRINT, YY_REDUCE_PRINT):
(YYCHK1):
Use /*CONSTCOND*/ to suppress lint warnings.
* data/lalr1.cc (YYLLOC_DEFAULT, YY_SYMBOL_PRINT, YY_REDUCE_PRINT):
(YY_STACK_PRINT): Use 'false' not '0'.
(YYUSE): New macro.
(yysymprint_, yydestruct_): Use it instead of rolling our own.
* data/yacc.c (YYUSE): New macro.
(YYCOPY, YYSTACK_RELOCATE, YYBACKUP, YYLLOC_DEFAULT):
(YYDPRINTF, YY_SYMBOL_PRINT, YY_STACK_PRINT, YY_REDUCE_PRINT):
(yyerrorlab): Use /*CONSTCOND*/ to suppress lint warnings.