THRIFT-916 compile with -Wall -Wextra without warning on Debian Lenny


git-svn-id: https://svn.apache.org/repos/asf/thrift/trunk@1036250 13f79535-47bb-0310-9956-ffa450edef68
diff --git a/lib/cpp/test/DebugProtoTest_extras.cpp b/lib/cpp/test/DebugProtoTest_extras.cpp
index e68c544..c89db74 100644
--- a/lib/cpp/test/DebugProtoTest_extras.cpp
+++ b/lib/cpp/test/DebugProtoTest_extras.cpp
@@ -25,6 +25,7 @@
 namespace thrift { namespace test { namespace debug {
 
 bool Empty::operator<(Empty const& other) const {
+  (void) other;
   // It is empty, so all are equal.
   return false;
 }