name_to_backref_number  977 ext/strscan/strscan.c name_to_backref_number(struct re_registers *regs, VALUE regexp, const char* name, const char* name_end, rb_encoding *enc)
name_to_backref_number 1819 re.c           name_to_backref_number(struct re_registers *regs, VALUE regexp, const char* name, const char* name_end)