kernel32: Disable diagnostics when testing corner cases in test_heap().

[Erich E. Hoover]

On Tue, Feb 21, 2017 at 9:16 AM, Gerald Pfeifer <gerald at pfeifer.com> wrote:
> ...
>
> Hmm, so here is an excerpt from the documentation of the forthcoming
> GCC 7 release about this warning:
>
>   Warn about calls to functions decorated with attribute @code{alloc_size}
>   that attempt to allocate objects larger than the specified number of
>   bytes, or where the result of the size computation in an integer type
>   with infinite precision would exceed @code{SIZE_MAX / 2}.
>
> (I believe this boils down to "half the address space", which indeed
> would be at least unusual for a memory allocation. ;-)

Ok, clearly I misunderstood the purpose of this specific warning.

Henri, do you know if we allow gcc-specific pragmas like this?  I
don't see anything like this in the current code, so it may be that we
need to make this something we detect at ./configure time.

Best,
Erich