diff --git a/0001-Remove-unused-not_supported-function.patch b/0001-Remove-unused-not_supported-function.patch
new file mode 100644
index 0000000..851385c
--- /dev/null
+++ b/0001-Remove-unused-not_supported-function.patch
@@ -0,0 +1,57 @@
+From 8853f5a49587f00a7d2a5c8c7e52480a16bbdb02 Mon Sep 17 00:00:00 2001
+From: "Richard W.M. Jones" <rjones@redhat.com>
+Date: Fri, 5 Feb 2016 16:28:34 +0000
+Subject: [PATCH] Remove unused 'not_supported' function.
+
+Found by compiling under GCC 6.  The warning was:
+
+In file included from libvirt_c.c:2058:0:
+libvirt_c_epilogue.c:89:1: error: 'not_supported' defined but not used [-Werror=unused-function]
+ not_supported (const char *fn)
+ ^~~~~~~~~~~~~
+---
+ libvirt/libvirt_c_epilogue.c | 15 ---------------
+ libvirt/libvirt_c_prologue.c |  1 -
+ 2 files changed, 16 deletions(-)
+
+diff --git a/libvirt/libvirt_c_epilogue.c b/libvirt/libvirt_c_epilogue.c
+index 4972e50..fa592c9 100644
+--- a/libvirt/libvirt_c_epilogue.c
++++ b/libvirt/libvirt_c_epilogue.c
+@@ -84,21 +84,6 @@ _raise_virterror (const char *fn)
+   (void) caml__frame;
+ }
+ 
+-/* Raise an error if a function is not supported. */
+-static void
+-not_supported (const char *fn)
+-{
+-  CAMLparam0 ();
+-  CAMLlocal1 (fnv);
+-
+-  fnv = caml_copy_string (fn);
+-  caml_raise_with_arg (*caml_named_value ("ocaml_libvirt_not_supported"), fnv);
+-
+-  /*NOTREACHED*/
+-  /* Suppresses a compiler warning. */
+-  (void) caml__frame;
+-}
+-
+ /* Convert the virErrorNumber, virErrorDomain and virErrorLevel enums
+  * into values (longs because they are variants in OCaml).
+  *
+diff --git a/libvirt/libvirt_c_prologue.c b/libvirt/libvirt_c_prologue.c
+index bf972e9..710c0d6 100644
+--- a/libvirt/libvirt_c_prologue.c
++++ b/libvirt/libvirt_c_prologue.c
+@@ -25,7 +25,6 @@ typedef value (*Val_ptr_t) (void *);
+ static value Val_opt (void *ptr, Val_ptr_t Val_ptr);
+ /*static value option_default (value option, value deflt);*/
+ static void _raise_virterror (const char *fn) Noreturn;
+-static void not_supported (const char *fn) Noreturn;
+ static value Val_virterror (virErrorPtr err);
+ 
+ /* Use this around synchronous libvirt API calls to release the OCaml
+-- 
+2.5.0
+
diff --git a/ocaml-libvirt.spec b/ocaml-libvirt.spec
index cfbbfbb..1e13d5a 100644
--- a/ocaml-libvirt.spec
+++ b/ocaml-libvirt.spec
@@ -2,7 +2,7 @@
 
 Name:           ocaml-libvirt
 Version:        0.6.1.4
-Release:        11%{?dist}
+Release:        12%{?dist}
 Summary:        OCaml binding for libvirt
 License:        LGPLv2+
 
@@ -19,6 +19,8 @@ Patch2:         0001-Add-a-binding-for-virDomainCreateXML.patch
 Patch3:         0001-Suppress-errors-to-stderr-and-use-thread-local-virEr.patch
 Patch4:         0002-Don-t-bother-checking-return-from-virInitialize.patch
 
+# Upstream patch to remove unused function.
+Patch5:         0001-Remove-unused-not_supported-function.patch
 
 BuildRequires:  ocaml >= 3.10.0
 BuildRequires:  ocaml-ocamldoc
@@ -50,6 +52,7 @@ developing applications that use %{name}.
 %patch2 -p1
 %patch3 -p1
 %patch4 -p1
+%patch5 -p1
 
 
 %build
@@ -97,6 +100,9 @@ make install-byte
 
 
 %changelog
+* Fri Feb 05 2016 Richard W.M. Jones <rjones@redhat.com> - 0.6.1.4-12
+- Add upstream patch to remove unused function.
+
 * Thu Feb 04 2016 Fedora Release Engineering <releng@fedoraproject.org> - 0.6.1.4-11
 - Rebuilt for https://fedoraproject.org/wiki/Fedora_24_Mass_Rebuild