Fix tls crash on startup if more than one RS contexts are created in one process.
diff --git a/libs/rs/rsScriptC.cpp b/libs/rs/rsScriptC.cpp
index 20088da..9da7766 100644
--- a/libs/rs/rsScriptC.cpp
+++ b/libs/rs/rsScriptC.cpp
@@ -62,6 +62,7 @@
 {
     Context::ScriptTLSStruct * tls =
     (Context::ScriptTLSStruct *)pthread_getspecific(Context::gThreadTLSKey);
+    rsAssert(tls);
 
     if (mEnviroment.mFragmentStore.get()) {
         rsc->setFragmentStore(mEnviroment.mFragmentStore.get());