diff --git a/src/plugins/subversion/subversionclient.cpp b/src/plugins/subversion/subversionclient.cpp
index d904255f28d..d5200f03faa 100644
--- a/src/plugins/subversion/subversionclient.cpp
+++ b/src/plugins/subversion/subversionclient.cpp
@@ -99,7 +99,7 @@ Id SubversionClient::vcsEditorKind(VcsCommandTag cmd) const
 }
 
 // Add authorization options to the command line arguments.
-CommandLine &operator<<(Utils::CommandLine &command, const SubversionClient::AddAuthOptions &addAuth)
+CommandLine &operator<<(Utils::CommandLine &command, SubversionClient::AddAuthOptions)
 {
     if (!s_settings->hasAuthentication())
         return command;
diff --git a/src/plugins/subversion/subversionclient.h b/src/plugins/subversion/subversionclient.h
index 5b0bdb230df..bdfebce0a5b 100644
--- a/src/plugins/subversion/subversionclient.h
+++ b/src/plugins/subversion/subversionclient.h
@@ -60,8 +60,7 @@ private:
     mutable QString m_svnVersion;
 };
 
-Utils::CommandLine &operator<<(Utils::CommandLine &command,
-                               const SubversionClient::AddAuthOptions &addAuth);
+Utils::CommandLine &operator<<(Utils::CommandLine &command, SubversionClient::AddAuthOptions);
 
 } // namespace Internal
 } // namespace Subversion