Add bug ref

src/Composer/Autoload/AutoloadGenerator.php

@@ -101,6 +101,7 @@ class AutoloadGenerator
         $filesystem->ensureDirectoryExists($config->get('vendor-dir'));
         // Do not remove double realpath() calls.
         // Fixes failing Windows realpath() implementation.
+        // See https://bugs.php.net/bug.php?id=72738
         $basePath = $filesystem->normalizePath(realpath(realpath(getcwd())));
         $vendorPath = $filesystem->normalizePath(realpath(realpath($config->get('vendor-dir'))));
         $useGlobalIncludePath = (bool) $config->get('use-include-path');