diff --git a/libmemcached.spec b/libmemcached.spec
index 923b490..0c5c6ee 100644
--- a/libmemcached.spec
+++ b/libmemcached.spec
@@ -43,6 +43,7 @@ Requires:      %{name}-libs%{?_isa} = %{version}-%{release}
 
 Patch0: libmemcached-fix-linking-with-libpthread.patch
 # Fix: ISO C++ forbids comparison between pointer and integer [-fpermissive]
+# https://bugs.launchpad.net/libmemcached/+bug/1663985
 Patch1: %{libname}-build.patch