The following spec errors out with:
*** Exception: Internal error: Type.typedExp. Expr: EPreEntry (AlexPn 246 15 11) "x"  CallStack (from HasCallStack): error, called at Type.hs:311:29 in act-0.1.0.0-inplace-act-internal:Type
constructor of C interface constructor(uint24 _x) creates uint24 x := _x behaviour ret of C interface ret() returns pre(x)
The issue is that
x is not declared in the
storage block of
ret, but the error message is terrible.