Andrew Kelley 5eaead6a56
implement allowzero pointer attribute
closes #1953

only needed for freestanding targets.

also adds safety for `@intToPtr` when the address is zero.
2019-03-25 12:55:45 -04:00
..
2018-11-13 05:08:37 -08:00
2019-03-18 20:09:27 -04:00