From 79dc621626baf4a23eb2e13d9eb620d260bba155 Mon Sep 17 00:00:00 2001
From: Tim Edwards <tim@opencircuitdesign.com>
Date: Fri, 28 Apr 2023 09:24:04 -0400
Subject: [PATCH] Added a warning message if attempting to extract an empty
 cell, so that it is not so mysterious as to why no output was generated.

---
 VERSION           | 2 +-
 extract/ExtMain.c | 7 +++++++
 2 files changed, 8 insertions(+), 1 deletion(-)

diff --git a/VERSION b/VERSION
index 89a770fc..0003b29f 100644
--- a/VERSION
+++ b/VERSION
@@ -1 +1 @@
-8.3.396
+8.3.397
diff --git a/extract/ExtMain.c b/extract/ExtMain.c
index 57ad2fc9..96c1fe71 100644
--- a/extract/ExtMain.c
+++ b/extract/ExtMain.c
@@ -379,6 +379,13 @@ ExtAll(rootUse)
 
     extDefListFunc(rootUse, &defList);
 
+    /* Sanity check---print wrning if there is nothing to extract */
+    if (defList == (LinkedDef *)NULL)
+    {
+	TxError("Warning:  There is nothing here to extract.\n");
+	return;
+    }
+
     /* Now reverse the list onto a stack such that the bottommost cell	*/
     /* is the first to be extracted, and so forth back up to the top.	*/