build, we cannot assume that PL_reg_starttry isn't needed. So copy it
in Perl_ss_dup.
p4raw-id: //depot/perl@27930
= pv_dup(old_state->re_state_reg_oldsaved);
new_state->re_state_reg_poscache
= pv_dup(old_state->re_state_reg_poscache);
-#ifdef DEBUGGING
new_state->re_state_reg_starttry
= pv_dup(old_state->re_state_reg_starttry);
-#endif
break;
}
case SAVEt_COMPILE_WARNINGS: