diff --git a/config/check_utils.py b/config/check_utils.py
index 5049a6fc099e..035402beb11f 100644
--- a/config/check_utils.py
+++ b/config/check_utils.py
@@ -7,13 +7,14 @@ import subprocess
 
 def get_all_toplevel_filenames():
     '''Get a list of all the files in the (Mercurial or Git) repository.'''
+    failed_cmds = []
     try:
         cmd = ['hg', 'manifest', '-q']
         all_filenames = subprocess.check_output(cmd, universal_newlines=True,
                                                 stderr=subprocess.PIPE).split('\n')
         return all_filenames
     except:
-        pass
+        failed_cmds.append(cmd)
 
     try:
         # Get the relative path to the top-level directory.
@@ -25,6 +26,6 @@ def get_all_toplevel_filenames():
                                                 stderr=subprocess.PIPE).split('\n')
         return all_filenames
     except:
-        pass
+        failed_cmds.append(cmd)
 
-    raise Exception('failed to run any of the repo manifest commands', cmds)
+    raise Exception('failed to run any of the repo manifest commands', failed_cmds)
diff --git a/js/src/jsweakmap.cpp b/js/src/jsweakmap.cpp
index fd42fc64e91f..6cfc8a6f65e0 100644
--- a/js/src/jsweakmap.cpp
+++ b/js/src/jsweakmap.cpp
@@ -119,8 +119,9 @@ WeakMapBase::sweepZone(JS::Zone* zone)
     }
 
 #ifdef DEBUG
-    for (WeakMapBase* m : zone->gcWeakMapList)
+    for (WeakMapBase* m : zone->gcWeakMapList) {
         MOZ_ASSERT(m->isInList() && m->marked);
+    }
 #endif
 }