diff --git a/client/deps/tinycbor/compilersupport_p.h b/client/deps/tinycbor/compilersupport_p.h
index 91d88229e..3223324d9 100644
--- a/client/deps/tinycbor/compilersupport_p.h
+++ b/client/deps/tinycbor/compilersupport_p.h
@@ -179,7 +179,9 @@
 #ifndef unlikely
 #  define unlikely(x)   __builtin_expect(!!(x), 0)
 #endif
+#ifndef unreachable
 #  define unreachable() __builtin_unreachable()
+#endif
 #elif defined(_MSC_VER)
 #  define likely(x)     (x)
 #  define unlikely(x)   (x)