Can anybody provide a MISRA C++ compliant 'offsetof' macro/template/function that works with static_assert?

I'm trying to write defensive code and put static_assert<> to ensure a structure's member has a specific offset to satisfy some hardware requirements

MISRA C++ Rule 18-2-1 says "The macro offsetof shall not be used", so we've 'undef'd offsetof.

We've provided some template things, but they all fail when used in static_assert<>

I've been unable to find something that works with C++11 static_assert<> across compilers.

struct Commands
{
    uint32_t command[4];
};

struct DMA_Bundle
{
    struct header_
    {
        uint32_t num_of_elems;
        uint8_t reserved[60];
    } header;
    Commands array[16];
};

I'm trying to assure that array is 64 bytes from the beginning.

static_assert(offsetof(DMA_Bundle,array)==64,"zoinks");

Does works, but MISRA says but I can't use that. (and I can't argue with our functional safety people :/)

I've tried the following, and generally they don't work:

static_assert(offsetofarray()==64,"bar");
static_assert(myoffsetof(DMA_Bundle::array)==64,"double_zoinks");

The explicit offsetofarray() constexpr function does work under GCC 7.5.0, but it fails under later GCC and Clang (which is what our embedded processor tools use). It fails with 'non constant condition for static_assert'.

The other seems to complain of "invalid use of non-static data member 'DMA_Bundle::array'"

And, for what it's worth, I'm limited to C++11.