Incomplete array generated wrong layout

[flier]

As you know, GNU C and C++ supports Arrays of Length Zero in different syntax. For int A[], LLVM has a IncompleteArrayType where the size is unspecified.

For example, we have two array in a class

class C {
    int a;
    // More than rust limits (32)
    char big_array[33];
    char zero_length_array[0];
    char incomplete_array[];
};

The incomplete array will be generated as a pointer, which cause the layout test failed

#[repr(C)]
 pub struct C {
     pub a: ::std::os::raw::c_int,
     pub big_array: [::std::os::raw::c_char; 33usize],
     pub zero_length_array: [::std::os::raw::c_char; 0usize],
     pub incomplete_array: *mut ::std::os::raw::c_char,
}
 #[test]
 fn bindgen_test_layout_C() {
     assert_eq!(::std::mem::size_of::<C>() , 40usize);
     assert_eq!(::std::mem::align_of::<C>() , 4usize);
 }

failures:

---- bindgen_test_layout_C stdout ----
thread 'bindgen_test_layout_C' panicked at 'assertion failed: (left == right) (left: 48, right: 40)', tests/class.rs:40

We should treat the incomplete array as a zero length array, or add a helper class like __BindgenUnionField<T> did.

[emilio]

This is fixed now. I'm landing tests for its use in statics here: #457

[emilio]

Thanks again for fixing this :)