my @extvars = qw(sv_undef sv_yes sv_no na dowarn
curcop compiling
tainting tainted stack_base stack_sp sv_arenaroot
+ no_modify
curstash DBsub DBsingle debstash
rsfp
stdingv
dopoptosub_at
save_lines
doeval
+ sv_ncmp
+ sv_i_ncmp
+ amagic_ncmp
+ amagic_i_ncmp
amagic_cmp
amagic_cmp_locale
mul128
study_chunk
add_data
re_croak2
+ regpposixcc
+ clear_re
regmatch
regrepeat
regrepeat_hard
regcppop
regcp_set_to
cache_re
+ restore_pos
reghop
reghopmaybe
dump
debprof
bset_obj_store
new_logop
+ simplify_sort
+ is_handle_constructor
do_trans_CC_simple
do_trans_CC_count
do_trans_CC_complex