It is hard to say without seeing your implementation, but it seems as to me that '(' and ')' should be checked in the higher levels. 
 
lv1expr   : lv2expr ADD lv1expr
          | '(' lv2expr ADD lv1expr ')'

[download]

It's not as pretty as what you have, but it doesn’t recurse as far for things that are technically level one exprs parens shouldn’t change the rule your matching, they are just there for precedence right? You still need to match the sub expr, which is just a lv1expr or lv2expr. Consider how deep you would have to go in the current grammar to parse ((((A + B)*A+C)*D)+X). This seems unnecessary. Again, I don’t know the whole situation, perhaps i am missing something.
hope this helps, good luck.

In reply to Re: Parse::RecDescent Puzzlement by krujos
in thread Parse::RecDescent Puzzlement by Android 18

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