diff --git a/app/models/repository.rb b/app/models/repository.rb
index 86c4cc10b0..fd752b639d 100644
--- a/app/models/repository.rb
+++ b/app/models/repository.rb
@@ -541,7 +541,6 @@ class Repository
   def upstream_branches
     rugged.references.each("refs/remotes/#{Repository::MIRROR_REMOTE}/*").map do |ref|
       name = ref.name.sub(/\Arefs\/remotes\/#{Repository::MIRROR_REMOTE}\//, "")
-      source_sha = ref.target.oid
 
       begin
         Gitlab::Git::Branch.new(name, ref.target)