references are noalias

Author: mahkoh

text/0000-noalias.md

@@ -74,6 +74,10 @@ If `x` and `y` are different noalias pointers and `a` and `b` are two pointers
 `x` and `y` respectively, then memory access via `a` and `b` does not
 alias.
 
+If `x` is a noalias pointer, `y` is a reference, and `a` and `b` are two
+pointers based on `x` and `y` respectively, then memory access via `a` and `b`
+does not alias.
+
 If `x` is a noalias pointer, `a` is based on `x`, and `b` is any pointer, then
 memory access via `a` and `b` does not alias unless `b` is based on `x`.