For instance this header file:

    struct Foo {
        struct {
            int x;
            int y;
        } x;
    };

    struct Bar {
        struct {
            int z;
        } x;
    };

jextract running in source mode will only generate one layout field:

    static final MemoryLayout x$struct$LAYOUT_ = MemoryLayout.ofStruct(
        C_INT.withName("x"),
        C_INT.withName("y")
    );

That is then referenced for both fields.

While the fields have the same names, the layouts are unrelated, so 2 layouts should be generated.