Rtos API example

Revision:
0:9fca2b23d0ba
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/mbed-os/TESTS/mbedmicro-mbed/attributes/weak.c	Sat Feb 23 12:13:36 2019 +0000
@@ -0,0 +1,10 @@
+#include "mbed_toolchain.h"
+
+int testWeak1() {
+    return 0;
+}
+
+MBED_WEAK int testWeak2() {
+    return 1;
+}
+