Re: [PATCH 1/1] poll: use GetTickCount64() to avoid wrap-around issues

> From: Steve Hoelzer <shoelzer@gmail.com>
> 
>  From Visual Studio 2015 Code Analysis: Warning C28159 Consider using
> 'GetTickCount64' instead of 'GetTickCount'.
> 
> Reason: GetTickCount() overflows roughly every 49 days. Code that does
> not take that into account can loop indefinitely. GetTickCount64()
> operates on 64 bit values and does not have that problem.
> 
> Note: this patch has been carried in Git for Windows for almost two
> years, but with a fallback for Windows XP, as the GetTickCount64()
> function is only available on Windows Vista and later. However, in the
> meantime we require Vista or later, hence we can drop that fallback.
> 
> Signed-off-by: Steve Hoelzer <shoelzer@gmail.com>
> Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
> ---
>   compat/poll/poll.c | 10 +++++++---
>   1 file changed, 7 insertions(+), 3 deletions(-)
> 
> diff --git a/compat/poll/poll.c b/compat/poll/poll.c
> index ad5dcde439..4abbfcb6a4 100644
> --- a/compat/poll/poll.c
> +++ b/compat/poll/poll.c
> @@ -18,6 +18,9 @@
>      You should have received a copy of the GNU General Public License along
>      with this program; if not, see <http://www.gnu.org/licenses/>.  */
>   
> +/* To bump the minimum Windows version to Windows Vista */
> +#include "git-compat-util.h"
> +
>   /* Tell gcc not to warn about the (nfd < 0) tests, below.  */
>   #if (__GNUC__ == 4 && 3 <= __GNUC_MINOR__) || 4 < __GNUC__
>   # pragma GCC diagnostic ignored "-Wtype-limits"
> @@ -449,7 +452,8 @@ poll (struct pollfd *pfd, nfds_t nfd, int timeout)
>     static HANDLE hEvent;
>     WSANETWORKEVENTS ev;
>     HANDLE h, handle_array[FD_SETSIZE + 2];
> -  DWORD ret, wait_timeout, nhandles, start = 0, elapsed, orig_timeout = 0;
> +  DWORD ret, wait_timeout, nhandles, elapsed, orig_timeout = 0;
> +  ULONGLONG start = 0;
>     fd_set rfds, wfds, xfds;
>     BOOL poll_again;
>     MSG msg;
> @@ -465,7 +469,7 @@ poll (struct pollfd *pfd, nfds_t nfd, int timeout)
>     if (timeout != INFTIM)
>       {
>         orig_timeout = timeout;
> -      start = GetTickCount();
> +      start = GetTickCount64();
>       }
>   
>     if (!hEvent)
> @@ -614,7 +618,7 @@ restart:
>   
>     if (!rc && orig_timeout && timeout != INFTIM)
>       {
> -      elapsed = GetTickCount() - start;
> +      elapsed = (DWORD)(GetTickCount64() - start);