go spec: inside functions, variables must be evaluated.
go spec: inside functions, variables must be evaluated.

Fixes issue 1612.

R=r, rsc, iant, ken, remyoudompheng, ken, r
CC=golang-dev
http://codereview.appspot.com/5700068

h8liu/golang,h8liu/golang,h8liu/golang,h8liu/golang,h8liu/golang,h8liu/golang,h8liu/golang