PERLVAR(IArgv, char **) /* stuff to free from do_aexec, vfork safe */
PERLVAR(ICmd, char *) /* stuff to free from do_aexec, vfork safe */
PERLVAR(Imystrk, SV *) /* temp key string for do_each() */
-PERLVAR(Idumplvl, I32) /* indentation level on syntax tree dump */
PERLVAR(Ioldlastpm, PMOP *) /* for saving regexp context in debugger */
PERLVAR(Igensym, I32) /* next symbol for getsym() to define */
PERLVAR(Ipreambled, bool)