Restore compatibility with rustc pre-1.38

dtolnay · dtolnay · commit f3fe8bdd043c · 2021-01-10T17:25:29.000-08:00
diff --git a/src/error.rs b/src/error.rs
@@ -730,7 +730,7 @@ pub(crate) struct ErrorImpl<E = ()> {
 // avoids converting `p` into a reference.
 unsafe fn vtable(p: NonNull<ErrorImpl>) -> &'static ErrorVTable {
     // NOTE: This assumes that `ErrorVTable` is the first field of ErrorImpl.
-    *p.as_ptr().cast::<&'static ErrorVTable>()
+    *(p.as_ptr() as *const &'static ErrorVTable)
 }
 
 // repr C to ensure that ContextError<C, E> has the same layout as

Original file line number	Diff line number	Diff line change
`@@ -730,7 +730,7 @@ pub(crate) struct ErrorImpl<E = ()> {`
`730`	`730`	// avoids converting `p` into a reference.
`731`	`731`	`unsafe fn vtable(p: NonNull<ErrorImpl>) -> &'static ErrorVTable {`
`732`	`732`	// NOTE: This assumes that `ErrorVTable` is the first field of ErrorImpl.
`733`		`- *p.as_ptr().cast::<&'static ErrorVTable>()`
	`733`	`+ (p.as_ptr() as const &'static ErrorVTable)`
`734`	`734`	`}`
`735`	`735`
`736`	`736`	`// repr C to ensure that ContextError<C, E> has the same layout as`