Update ReadMe.md
diff --git a/ReadMe.md b/ReadMe.md
index bd7266b..73fbf4c 100644
--- a/ReadMe.md
+++ b/ReadMe.md
@@ -7,5 +7,6 @@
 To take advantage of this file just include it in your project that uses ARM NEON intinsics instead of "arm_neon.h", compile it as usual and enjoy the result.
 
 For significant performance improvement in some cases you might need to define USE_SSE4 in your project settings. Otherwise SIMD up to SSSE3 to be used.
+If NEON2SSE_DISABLE_PERFORMANCE_WARNING macro is defined, then the performance warnings are disabled.
 
 For more information and license please read the NEON_2_SSE.h content.