This has been discussed here: http://gcc.gnu.org/ml/gcc-patches/2004-01/msg03141.html
-- Summary: alias analysis doesn't take into account that variables that haven't their address taken can't alias arbitrary MEMs Product: gcc Version: 3.2 Status: UNCONFIRMED Keywords: alias Severity: normal Priority: P2 Component: rtl-optimization AssignedTo: unassigned at gcc dot gnu dot org ReportedBy: amylaar at gcc dot gnu dot org CC: gcc-bugs at gcc dot gnu dot org OtherBugsDependingO 17652 nThis: http://gcc.gnu.org/bugzilla/show_bug.cgi?id=20367