diff --git a/Library/Homebrew/extend/os/linux/cmd/update-report.rb b/Library/Homebrew/extend/os/linux/cmd/update-report.rb
index 2d448f0ec1..25947f07c4 100644
--- a/Library/Homebrew/extend/os/linux/cmd/update-report.rb
+++ b/Library/Homebrew/extend/os/linux/cmd/update-report.rb
@@ -1,13 +1,15 @@
-# typed: true
+# typed: strict
 # frozen_string_literal: true
 
 module Homebrew
   module_function
 
+  sig { returns(String) }
   def no_changes_message
     "No changes to formulae."
   end
 
+  sig { void }
   def migrate_gcc_dependents_if_needed
     return if Settings.read("gcc-rpaths.fixed") == "true"