Use memoffset::offset_of instead of homegrown macro

The homegrown macro was fine in 2016, but at some point it technically
became UB.  The memoffset crate does the same thing, but avoids UB when
using rustc 1.51.0 or later.

Fixes #1415

1 files changed, 1 insertions, 0 deletions

diff --git a/src/sys/socket/addr.rs b/src/sys/socket/addr.rs
index 1f7f4ec6..71b2c973 100644
--- a/src/sys/socket/addr.rs
+++ b/src/sys/socket/addr.rs
@@ -1,6 +1,7 @@
 use super::sa_family_t;
 use crate::{Error, Result, NixPath};
 use crate::errno::Errno;
+use memoffset::offset_of;
 use std::{fmt, mem, net, ptr, slice};
 use std::ffi::OsStr;
 use std::hash::{Hash, Hasher};