diff --git a/include/mbedtls/ssl_internal.h b/include/mbedtls/ssl_internal.h
index 73279a5..78c748c 100644
--- a/include/mbedtls/ssl_internal.h
+++ b/include/mbedtls/ssl_internal.h
@@ -41,7 +41,8 @@
 #include "sha512.h"
 #endif
 
-#if ( defined(__ARMCC_VERSION) || defined(_MSC_VER) ) && !defined(inline)
+#if ( defined(__ARMCC_VERSION) || defined(_MSC_VER) ) && \
+    !defined(inline) && !defined(__cplusplus)
 #define inline __inline
 #endif