Hello there,
cexp.y:532:20: warning: logical not is only applied to the left hand side of comparison [-Wlogical-not-parentheses]
        if (!pedantic < spec_long)
          yyerror ("too many `l's in integer constant");
!pedantic is a boolean, so comparing it < spec_long looks like a
possible bug. Suggest code rework.
Regards
David Binderman