diff -r 287f76b3f502 -r 95e45abe7e8e mercurial/posix.py
--- a/mercurial/posix.py	Sat Feb 18 20:10:19 2012 +0100
+++ b/mercurial/posix.py	Thu Mar 08 20:17:36 2012 +0000
@@ -270,6 +270,13 @@
 
         return encodingupper(path)
 
+    # Cygwin translates native ACLs to POSIX permissions,
+    # but these translations are not supported by native
+    # tools, so the exec bit tends to be set erroneously.
+    # Therefore, disable executable bit access on Cygwin.
+    def checkexec(path):
+        return False
+
 def shellquote(s):
     if os.sys.platform == 'OpenVMS':
         return '"%s"' % s