diff --git a/include/asterisk/lock.h b/include/asterisk/lock.h
index f2fbd16a82a9f6e47485c78c8732a1a1a3f04fdd..2f63ee183e5964cabf7081cbf3a4eadcb5d65c71 100644
--- a/include/asterisk/lock.h
+++ b/include/asterisk/lock.h
@@ -705,6 +705,8 @@ AST_INLINE_API(int ast_atomic_dec_and_test(volatile int *p),
 #define ast_channel_trylock(x)		ast_mutex_trylock(&x->lock)
 #else
 
+struct ast_channel;
+
 /*! \brief Lock AST channel (and print debugging output)
 \note You need to enable DEBUG_CHANNEL_LOCKS for this function */
 int ast_channel_lock(struct ast_channel *chan);