diff --git a/src/buffer.c b/src/buffer.c
index 4dbb9e9..4510078 100644
--- a/src/buffer.c
+++ b/src/buffer.c
@@ -249,7 +249,7 @@
 	netbeansFireChanges = oldFire;
 #endif
 	/* Help buffer is filtered. */
-	if (curbuf->b_help)
+	if (bt_help(curbuf))
 	    fix_help_buffer();
     }
     else if (read_stdin)
@@ -5669,6 +5669,15 @@
 }
 
 /*
+ * Return TRUE if "buf" is a help buffer.
+ */
+    int
+bt_help(buf_T *buf)
+{
+    return buf != NULL && buf->b_help;
+}
+
+/*
  * Return TRUE if "buf" is a "nofile", "acwrite" or "terminal" buffer.
  * This means the buffer name is not a file name.
  */