------- Additional Comments From pinskia at gcc dot gnu dot org 2005-04-13 19:16 ------- We just don't generate any RTL for "i = i".
The optimization for f in comment #0 happens in combine for 3.4.0, so maybe fold could do it, I don't know. -- http://gcc.gnu.org/bugzilla/show_bug.cgi?id=21000
