Auto merge of #44678 - alexcrichton:rollup, r=alexcrichton

Rollup of 11 pull requests

- Successful merges: #44364, #44466, #44537, #44548, #44640, #44651, #44657, #44661, #44668, #44671, #44675
- Failed merges:

1 files changed, 3 insertions, 6 deletions

diff --git a/src/libstd/sys_common/memchr.rs b/src/libstd/sys_common/memchr.rs
index 3824a5fb528..50f998eb486 100644
--- a/src/libstd/sys_common/memchr.rs
+++ b/src/libstd/sys_common/memchr.rs
@@ -65,15 +65,12 @@ pub mod fallback {
         let usize_bytes = mem::size_of::<usize>();
 
         // search up to an aligned boundary
-        let align = (ptr as usize) & (usize_bytes- 1);
-        let mut offset;
-        if align > 0 {
-            offset = cmp::min(usize_bytes - align, len);
+        let mut offset = ptr.align_offset(usize_bytes);
+        if offset > 0 {
+            offset = cmp::min(offset, len);
             if let Some(index) = text[..offset].iter().position(|elt| *elt == x) {
                 return Some(index);
             }
-        } else {
-            offset = 0;
         }
 
         // search the body of the text