Data type for aio_buf under X32?

Hi Everyone,

My apologies for this question and my confusion.

When interfacing with the kernel crypto through AF_ALG, what is the
type of 'aio_buf' under X32?

I know is X32 uses ILP32 data model, so integers/longs/pointers are
32-bits (cf., http://www.unix.org/version2/whatsnew/lp64_wp.html). I
believe Glibc uses a 'void*' for 'aio_buf' (cf.,
http://man7.org/linux/man-pages/man7/aio.7.html). But I believe the
kernel's 'aio_buf' is a u64 under X32.

I'm asking due a failure under X32 because GCC sign extends the
pointer value when upsizing to 64-bits (cf., GCC manual 4.7 Arrays and
Pointers, http://gcc.gnu.org/onlinedocs/gcc/Arrays-and-pointers-implementation.html).

Thanks in advance.

Jeff