diff --git a/strace.spec b/strace.spec
index a48c30c..a7c8a4a 100644
--- a/strace.spec
+++ b/strace.spec
@@ -1,12 +1,16 @@
 Summary: Tracks and displays system calls associated with a running process
 Name: strace
 Version: 4.11
-Release: 1%{?dist}
+Release: 2%{?dist}
 License: BSD
 Group: Development/Debuggers
 URL: http://sourceforge.net/projects/strace/
 Source: http://downloads.sourceforge.net/strace/%{name}-%{version}.tar.xz
 BuildRequires: libacl-devel, time
+%ifarch x86_64
+# for experimental -k option
+BuildRequires: libunwind-devel
+%endif
 %define strace64_arches ppc64 sparc64
 
 %description
@@ -77,6 +81,9 @@ make -k check VERBOSE=1
 %endif
 
 %changelog
+* Wed Dec 23 2015 Dmitry V. Levin <ldv@altlinux.org> - 4.11-2
+- Enabled experimental -k option on x86_64 (#1170296).
+
 * Mon Dec 21 2015 Dmitry V. Levin <ldv@altlinux.org> - 4.11-1
 - New upstream release:
   + print nanoseconds along with seconds in stat family syscalls (#1251176).