diff --git a/examples/c/circular_buffer/circular_buffer.h b/examples/c/circular_buffer/circular_buffer.h
index 1584331..9d8ed1a 100644
--- a/examples/c/circular_buffer/circular_buffer.h
+++ b/examples/c/circular_buffer/circular_buffer.h
@@ -10,7 +10,8 @@ typedef struct circular_buf_t circular_buf_t;
 typedef circular_buf_t* cbuf_handle_t;
 
 /// Pass in a storage buffer and size, returns a circular buffer handle
-/// Requires: buffer is not NULL, size > 0
+/// Requires: buffer is not NULL, size > 0 (size > 1 for the threadsafe
+//  version, because it holds size - 1 elements)
 /// Ensures: cbuf has been created and is returned in an empty state
 cbuf_handle_t circular_buf_init(uint8_t* buffer, size_t size);
 
diff --git a/examples/c/circular_buffer/circular_buffer_no_modulo_threadsafe.c b/examples/c/circular_buffer/circular_buffer_no_modulo_threadsafe.c
index 484662a..2049939 100644
--- a/examples/c/circular_buffer/circular_buffer_no_modulo_threadsafe.c
+++ b/examples/c/circular_buffer/circular_buffer_no_modulo_threadsafe.c
@@ -47,7 +47,7 @@ static void retreat_pointer(cbuf_handle_t cbuf)
 
 cbuf_handle_t circular_buf_init(uint8_t* buffer, size_t size)
 {
-	assert(buffer && size);
+	assert(buffer && size > 1);
 
 	cbuf_handle_t cbuf = malloc(sizeof(circular_buf_t));
 	assert(cbuf);
@@ -150,7 +150,7 @@ bool circular_buf_empty(cbuf_handle_t cbuf)
 {
 	assert(cbuf);
 
-    return (!circular_buf_full(cbuf) && (cbuf->head == cbuf->tail));
+    return cbuf->head == cbuf->tail;
 }
 
 bool circular_buf_full(circular_buf_t* cbuf)