gcc ripped out its bison-generated parsers in favor of recursive descent parsers long ago, for exactly this reason (also, because C++ isn't LR-n for any n, so t

gcc ripped out its bison-generated parsers in favor of recursive descent parsers long ago, for exactly this reason (also, because C++ isn't LR-n for any n, so to get bison to work as well a third pass called "spew" sat between the lexer and the Bison parser so it could do arbitrary lookahead to figure out what the tokens were).