http://gcc.gnu.org/bugzilla/show_bug.cgi?id=47763
Summary: Useless initialization of register Product: gcc Version: 4.6.0 Status: UNCONFIRMED Severity: normal Priority: P3 Component: rtl-optimization AssignedTo: unassig...@gcc.gnu.org ReportedBy: j...@gcc.gnu.org For arm-eabi target and options "-O2 -funroll-loops", gcc compiles the following empty function foo() { } to foo: mov r0, #0 bx lr Apparently the first instruction is useless.