Introduce a cast as a workaround for missing inout constructors.

std/range.d

@@ -4421,7 +4421,8 @@ nothrow:
 
     inout(typeof(this)) opSlice(size_t i, DollarToken) inout
     {
-        return Cycle(*cast(R*)_ptr, _index + i);
+        // cast: Issue 12177 workaround
+        return cast(typeof(return))Cycle(*cast(R*)_ptr, _index + i);
     }
 }
 
@@ -4587,6 +4588,11 @@ unittest //10845
     assert(equal(cycle(a).take(10), [0, 1, 2, 0, 1, 2, 0, 1, 2, 0]));
 }
 
+unittest // 12177
+{
+    auto a = recurrence!q{a[n - 1] ~ a[n - 2]}("1", "0");
+}
+
 private alias lengthType(R) = typeof(R.init.length.init);
 
 /**