This is very similar to https://issues.dlang.org/show_bug.cgi?id=17518 . The code below should yield the same errors as it would without the `inout`:

Error: function `bug.A.f(short x)` is not callable using argument types `(int)` cannot pass argument `cast(int)y + 1` of type `int` to parameter `short x`

Instead I get this unhelpful nonsense:

Error: `inout` method `bug.A.f` is not callable using a mutable object
//////////////////////////////////
module bug;

struct A {
	void f(short x) inout { }
}

void main() {
	short y = 5;
	A().f(y + 1);
}