--- a/build/pgo/profileserver.py
+++ b/build/pgo/profileserver.py
@@ -1,16 +1,17 @@
 #!/usr/bin/python
 #
 # This Source Code Form is subject to the terms of the Mozilla Public
 # License, v. 2.0. If a copy of the MPL was not distributed with this
 # file, You can obtain one at http://mozilla.org/MPL/2.0/.
 
 import json
 import os
+import sys
 
 from buildconfig import substs
 from mozbuild.base import MozbuildObject
 from mozfile import TemporaryDirectory
 from mozhttpd import MozHttpd
 from mozprofile import FirefoxProfile, Profile, Preferences
 from mozprofile.permissions import ServerLocations
 from mozrunner import FirefoxRunner, CLI
@@ -81,24 +82,32 @@ if __name__ == '__main__':
 
         # Run Firefox a first time to initialize its profile
         runner = FirefoxRunner(profile=profile,
                                binary=build.get_binary_path(
                                    where="staged-package"),
                                cmdargs=['javascript:Quitter.quit()'],
                                env=env)
         runner.start()
-        runner.wait()
+        ret = runner.wait()
+        if ret:
+            print("Firefox exited with code %d during profile initialization"
+                  % ret)
+            httpd.stop()
+            sys.exit(ret)
 
         jarlog = os.getenv("JARLOG_FILE")
         if jarlog:
             env["MOZ_JAR_LOG_FILE"] = os.path.abspath(jarlog)
             print "jarlog: %s" % env["MOZ_JAR_LOG_FILE"]
 
         cmdargs = ["http://localhost:%d/index.html" % PORT]
         runner = FirefoxRunner(profile=profile,
                                binary=build.get_binary_path(
                                    where="staged-package"),
                                cmdargs=cmdargs,
                                env=env)
         runner.start(debug_args=debug_args, interactive=interactive)
-        runner.wait()
+        ret = runner.wait()
         httpd.stop()
+        if ret:
+            print("Firefox exited with code %d during profiling" % ret)
+            sys.exit(ret)