Issue #7512: shutil.copystat() could raise an OSError when the filesystem
didn't support chflags() (for example ZFS under FreeBSD).  The error is
now silenced.
diff --git a/Lib/shutil.py b/Lib/shutil.py
index df571e7..0dfc7c7 100644
--- a/Lib/shutil.py
+++ b/Lib/shutil.py
@@ -11,6 +11,7 @@
 import fnmatch
 from warnings import warn
 import collections
+import errno
 
 try:
     from pwd import getpwnam
@@ -105,8 +106,11 @@
     if hasattr(os, 'chmod'):
         os.chmod(dst, mode)
     if hasattr(os, 'chflags') and hasattr(st, 'st_flags'):
-        os.chflags(dst, st.st_flags)
-
+        try:
+            os.chflags(dst, st.st_flags)
+        except OSError, why:
+            if not hasattr(errno, 'EOPNOTSUPP') or why.errno != errno.EOPNOTSUPP:
+                raise
 
 def copy(src, dst):
     """Copy data and mode bits ("cp src dst").