Do not warn the user when 'madvise' returns ENOSYS.

* libguile/vm.c (return_unused_stack_to_os): Avoid 'perror' calls when
'madvise' returns ENOSYS.

diff --git a/libguile/vm.c b/libguile/vm.c
index c8ec6e1b2fc27720087e2f6c955721647ff3e9d8..c313119e7288289de1ec608fdc9e60a1f727ca47 100644 (file)
--- a/libguile/vm.c
+++ b/libguile/vm.c
@@ -1,4 +1,4 @@
-/* Copyright (C) 2001, 2009, 2010, 2011, 2012, 2013, 2014, 2015 Free Software Foundation, Inc.
+/* Copyright (C) 2001, 2009, 2010, 2011, 2012, 2013, 2014, 2015, 2018 Free Software Foundation, Inc.
  * 
  * This library is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Lesser General Public License
@@ -904,7 +904,10 @@ return_unused_stack_to_os (struct scm_vm *vp)
         ret = madvise ((void *) lo, hi - lo, MADV_DONTNEED);
       while (ret && errno == EAGAIN);
 
-      if (ret)
+      /* If the OS doesn't implement 'madvise' (as is currently the case
+         for GNU/Hurd), don't warn the user since there's nothing they
+         can do about it.  */
+      if (ret && errno != ENOSYS)
         perror ("madvise failed");
     }