doc: explain how to use "go vet -shadow"
Fixes #29260
Change-Id: I419b74d06380113f4bd32b9aeb053c3be36208d5
Reviewed-on: https://go-review.googlesource.com/c/154584
Reviewed-by: Alan Donovan <adonovan@google.com>
diff --git a/doc/go1.12.html b/doc/go1.12.html
index 54ebed5..66c37d5 100644
--- a/doc/go1.12.html
+++ b/doc/go1.12.html
@@ -93,6 +93,16 @@
vet</code> should work with all supported versions of Go.
</p>
+<p>
+ As part of this change, the experimental <code>-shadow</code> option
+ is no longer available with <code>go vet</code>. Checking for
+ variable shadowing may now be done using
+ <pre>
+ go install golang.org/x/tools/go/analysis/passes/shadow/cmd/shadow
+ go vet -vettool=$(which shadow)
+ </pre>
+</p>
+
<h3 id="gocache">Build cache requirement</h3>
<p>
