https://gcc.gnu.org/bugzilla/show_bug.cgi?id=92008
--- Comment #17 from Akim Demaille <akim.demaille at gmail dot com> --- Hi Jakub, I'm not claiming you should require 3.0, I'm claiming there's no reason to target 1.35, there is no evidence there's a need for it. So there's no reason to pay for "PARSE_PARAMS" support. "%require" was introduced in 2.2 (2006-05-19). Even Apple ships 2.3, stuck to the last GPLv2 release. So I suggest that you add "%require 2.2" and just use %parse-param. But if you think 2.2 is too much to ask for, just use %parse-param (Bison 1.875). Cheers!