hi, all, from the web i find the definition is: .cfi_def_cfa defines a rule for computing CFA as: take adress from register and add offeset to it. There is a concept CFA i can't understand, what means of the CFA, and this address point to where? Best Regards! Bai Shuwei -- Add: Tianshui South Road 222, Lanzhou, P.R.China Tel: +86-931-8912025 Zip Code: 730000 Email: baishuwei@gmail.com, buroc@126.com