Don't exit if we can't work out if we're running in a git repo

synapse/app/homeserver.py

@@ -210,6 +210,7 @@ class SynapseHomeServer(HomeServer):
 
 
 def get_version_string():
+    try:
         null = open(os.devnull, 'w')
         cwd = os.path.dirname(os.path.abspath(__file__))
         try:
@@ -265,6 +266,8 @@ def get_version_string():
                     synapse.__version__, git_version,
                 )
             ).encode("ascii")
+    except Exception as e:
+        logger.warn("Failed to check for git repository: %s", e)
 
     return ("Synapse/%s" % (synapse.__version__,)).encode("ascii")