use build tags

errcheck/embedded_walker.go

@@ -84,8 +84,8 @@ func walkThroughEmbeddedInterfaces(sel *types.Selection) ([]types.Type, bool) {
 }
 
 func getTypeAtFieldIndex(startingAt types.Type, fieldIndex int) types.Type {
-	t := maybeDereference(types.Unalias(startingAt))
-	t = maybeUnname(types.Unalias(t))
+	t := maybeDereference(maybeUnalias(startingAt))
+	t = maybeUnname(maybeUnalias(t))
 	s, ok := t.(*types.Struct)
 	if !ok {
 		panic(fmt.Sprintf("cannot get Field of a type that is not a struct, got a %T", t))

errcheck/embedded_walker_121.go

@@ -0,0 +1,10 @@
+//go:build !go1.22
+// +build !go1.22
+
+package errcheck
+
+import "go/types"
+
+func maybeUnalias(t types.Type) types.Type {
+	return t
+}

errcheck/embedded_walker_122.go

@@ -0,0 +1,10 @@
+//go:build go1.22
+// +build go1.22
+
+package errcheck
+
+import "go/types"
+
+func maybeUnalias(t types.Type) types.Type {
+	return types.Unalias(t)
+}