foo.ll

; Before

; Function Attrs: inlinehint nounwind
define i64 @foo() #0 {
entry:
  %0 = call i64 @foo()
  ret i64 %0
}


; After

; Function Attrs: inlinehint nounwind readnone
define i64 @foo() #0 {
entry:
  ret i64 undef
}