fix #47410, syntax error with anonfn inside elseif and short-circui…

…t op (#47499)

(cherry picked from commit 5f256e7)

src/julia-syntax.scm

@@ -4309,6 +4309,9 @@ f(x) = yt(x)
             cnd)))
     (define (emit-cond cnd break-labels endl)
       (let* ((cnd (if (and (pair? cnd) (eq? (car cnd) 'block))
+                      (flatten-ex 'block cnd)
+                      cnd))
+             (cnd (if (and (pair? cnd) (eq? (car cnd) 'block))
                        (begin (if (length> cnd 2) (compile (butlast cnd) break-labels #f #f))
                               (last cnd))
                        cnd))

test/syntax.jl

@@ -3297,3 +3297,10 @@ f45162(f) = f(x=1)
 @test Meta.lower(@__MODULE__, :(global const x::Int)) == Expr(:error, "expected assignment after \"const\"")
 @test Meta.lower(@__MODULE__, :(const global x)) == Expr(:error, "expected assignment after \"const\"")
 @test Meta.lower(@__MODULE__, :(const global x::Int)) == Expr(:error, "expected assignment after \"const\"")
+
+# issue #47410
+# note `eval` is needed since this needs to be at the top level
+@test eval(:(if false
+             elseif false || (()->true)()
+                 42
+             end)) == 42