diff --git a/src/insexpand.c b/src/insexpand.c
index 3cfdfac..b767b4e 100644
--- a/src/insexpand.c
+++ b/src/insexpand.c
@@ -3850,7 +3850,7 @@
 	else
 	{
 	    // Mark a buffer scanned when it has been scanned completely
-	    if (type == 0 || type == CTRL_X_PATH_PATTERNS)
+	    if (buf_valid(st.ins_buf) && (type == 0 || type == CTRL_X_PATH_PATTERNS))
 		st.ins_buf->b_scanned = TRUE;
 
 	    compl_started = FALSE;