Hello bug-standards readers, Autoconf 2.66 added '+' to the set of allowed characters in --enable-* and --with-* switches (mapping them to underscores for the variable name that they influence). Using these can cause problems in trees with older configures, or ones not made by Autoconf that are not prepared for plus signs.
So, my question is: could standards.texi document the set of allowed characters? Current Autoconf has -+. mapped to _ and otherwise wants characters eligible for shell variable names; but you may want to just allow more of them? Thanks, Ralf
