rb_vm_fstring_table  325 string.c           st_table *frozen_strings = rb_vm_fstring_table();
rb_vm_fstring_table 1216 string.c       	st_delete(rb_vm_fstring_table(), &fstr, NULL);
rb_vm_fstring_table 9832 string.c           assert(rb_vm_fstring_table());
rb_vm_fstring_table 9833 string.c           st_foreach(rb_vm_fstring_table(), fstring_set_class_i, rb_cString);