Add extern where its required
@ -39,7 +39,7 @@
/* helper for filters that need to host child channel stacks... handles
lifetime and upwards propagation cleanly */
const grpc_channel_filter grpc_child_channel_top_filter;
extern const grpc_channel_filter grpc_child_channel_top_filter;
typedef grpc_channel_stack grpc_child_channel;
typedef grpc_call_stack grpc_child_call;