Mark potentially unused argument with [[maybe_unused]] (#1697)

Summary: Pull Request resolved: https://github.com/facebook/folly/pull/1697

Reviewed By: Gownta

Differential Revision: D33483753

Pulled By: Orvid

fbshipit-source-id: d08291b5d02c61e461322edd332bb5a6e744ff96

folly/synchronization/detail/Hardware.cpp

@@ -23,6 +23,7 @@
 
 #include <boost/preprocessor/repetition/repeat.hpp>
 
+#include <folly/CppAttributes.h>
 #include <folly/lang/Assume.h>
 #include <folly/lang/Exception.h>
 
@@ -119,7 +120,8 @@ FOLLY_RTM_DISABLED_NORETURN static bool rtmTestFunc() {
 #endif
 }
 
-[[noreturn]] FOLLY_DISABLE_SANITIZERS static void rtmAbortFunc(uint8_t status) {
+[[noreturn]] FOLLY_DISABLE_SANITIZERS static void rtmAbortFunc(
+    FOLLY_MAYBE_UNUSED uint8_t status) {
 #if FOLLY_RTM_SUPPORT
   switch (status) {
 #define FOLLY_RTM_ABORT_ONE(z, n, text) \