ignore reserved identifier warnings (#249)

diff --git a/rpmalloc/rpmalloc.c b/rpmalloc/rpmalloc.c
index 996f56f..57042c1 100644
--- a/rpmalloc/rpmalloc.c
+++ b/rpmalloc/rpmalloc.c
@@ -20,6 +20,9 @@
 #if defined(__clang__)
 #pragma clang diagnostic ignored "-Wunused-macros"
 #pragma clang diagnostic ignored "-Wunused-function"
+#if __has_warning("-Wreserved-identifier")
+#pragma clang diagnostic ignored "-Wreserved-identifier"
+#endif
 #elif defined(__GNUC__)
 #pragma GCC diagnostic ignored "-Wunused-macros"
 #pragma GCC diagnostic ignored "-Wunused-function"