diff --git a/js/src/nanojit/nanojit.h b/js/src/nanojit/nanojit.h
index 07367a349f0a..d3fee308c42a 100644
--- a/js/src/nanojit/nanojit.h
+++ b/js/src/nanojit/nanojit.h
@@ -90,7 +90,7 @@
 #endif
 #ifdef JS_VALGRIND
 #  include <valgrind/valgrind.h>
-#else
+#elif !defined(VALGRIND_DISCARD_TRANSLATIONS)
 #  define VALGRIND_DISCARD_TRANSLATIONS(addr, szB)
 #endif