1 files changed, 2 insertions, 0 deletions
diff --git a/lib/http2.c b/lib/http2.c
index 1f4c6ffcc..eae8dac8d 100644
--- a/lib/http2.c
+++ b/lib/http2.c
@@ -1166,6 +1166,7 @@ static ssize_t http2_handle_stream_close(struct connectdata *conn,
     httpc->pause_stream_id = 0;
   }
 
+  DEBUGASSERT(httpc->drain_total >= data->state.drain);
   httpc->drain_total -= data->state.drain;
   data->state.drain = 0;
 
@@ -1471,6 +1472,7 @@ static ssize_t http2_recv(struct connectdata *conn, int sockindex,
                    stream->stream_id));
     }
     else if(!stream->closed) {
+      DEBUGASSERT(httpc->drain_total >= data->state.drain);
       httpc->drain_total -= data->state.drain;
       data->state.drain = 0; /* this stream is hereby drained */
     }