diff -r 2cceb4d3079a Tools/scripts/patchcheck.py
--- a/Tools/scripts/patchcheck.py	Tue Feb 21 17:26:10 2012 +0100
+++ b/Tools/scripts/patchcheck.py	Tue Feb 21 22:03:47 2012 +0100
@@ -36,6 +36,20 @@
     return decorated_fxn
 
 
+def mq_patches_applied():
+    """Check if at least one mq patch is applied
+
+    If some error occurred (may be because the mq extension is not active) we
+    ignore it.
+    """
+    cmd = 'hg qapplied'
+    with subprocess.Popen(cmd.split(),
+                          stdout=subprocess.PIPE,
+                          stderr=subprocess.PIPE) as st:
+        bstdout, _ = st.communicate()
+        return st.returncode == 0 and bstdout
+
+
 @status("Getting the list of files that have been added/changed",
         info=lambda x: n_files_str(len(x)))
 def changed_files():
@@ -44,6 +58,9 @@
         sys.exit('need a checkout to get modified files')
 
     cmd = 'hg status --added --modified --no-status'
+    if mq_patches_applied():
+        cmd += ' --rev qparent'
+
     with subprocess.Popen(cmd.split(), stdout=subprocess.PIPE) as st:
         return [x.decode().rstrip() for x in st.stdout]