fix oc lowering with return type annotations

fixes #44723

Author: simeonschaub

src/julia-syntax.scm

@@ -4119,7 +4119,7 @@ f(x) = yt(x)
            (cons (car e)
                  (map-cl-convert (cdr e) fname lam namemap defined toplevel interp opaq globals))))))))
 
-(define (closure-convert e) (cl-convert e #f #f #f #f #f #f #f))
+(define (closure-convert e) (cl-convert e #f #f (table) (table) #f #f #f))
 
 ;; pass 5: convert to linear IR
 
@@ -4403,7 +4403,10 @@ f(x) = yt(x)
                            (else
                             (compile-args (cdr e) break-labels))))
                     (callex (cons (car e) args)))
-               (cond (tail (emit-return callex))
+               (cond (tail (let ((tmp (make-ssavalue)))
+                             ;; can't just do (emit-return callex), since we might linearize code twice
+                             (emit `(= ,tmp ,callex))
+                             (emit-return tmp)))
                      (value callex)
                      (else (emit callex)))))
             ((=)

test/syntax.jl

@@ -3276,3 +3276,7 @@ end
     @test m.Foo.bar === 1
     @test Core.get_binding_type(m.Foo, :bar) == Any
 end
+
+# issue 44723
+demo44723(thunk)::Any = Base.Experimental.@opaque () -> true ? 1 : 2
+@test demo44723(7)() == 1