From ed78253c580c753e77dd6ed1e625c3fee1233881 Mon Sep 17 00:00:00 2001
From: Jordi Boggiano <j.boggiano@seld.be>
Date: Fri, 2 Sep 2016 18:43:44 +0200
Subject: [PATCH] Only update reference if there is actually a reference, fixes
 #5609

---
 src/Composer/Installer.php | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/src/Composer/Installer.php b/src/Composer/Installer.php
index bf221a125..49e82f06c 100644
--- a/src/Composer/Installer.php
+++ b/src/Composer/Installer.php
@@ -1137,6 +1137,10 @@ class Installer
 
     private function updateInstallReferences(PackageInterface $package, $reference)
     {
+        if (!$reference) {
+            return;
+        }
+
         $package->setSourceReference($reference);
         $package->setDistReference($reference);