From 7eecf4f8fb288dcc4a32595036421bfcc38699e6 Mon Sep 17 00:00:00 2001
From: John Ericson <John.Ericson@Obsidian.Systems>
Date: Thu, 31 Oct 2019 17:57:33 +0000
Subject: [PATCH] find-xml-catalogues: Ensure XML_CATALOG_FILES is defined

---
 pkgs/build-support/setup-hooks/find-xml-catalogs.sh | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/pkgs/build-support/setup-hooks/find-xml-catalogs.sh b/pkgs/build-support/setup-hooks/find-xml-catalogs.sh
index 85364a61f612..f446a6f27fd9 100644
--- a/pkgs/build-support/setup-hooks/find-xml-catalogs.sh
+++ b/pkgs/build-support/setup-hooks/find-xml-catalogs.sh
@@ -11,12 +11,12 @@ addXMLCatalogs () {
     done
 }
 
-if [ -z "$libxmlHookDone" ]; then
+if [ -z "${libxmlHookDone-}" ]; then
     libxmlHookDone=1
 
     # Set up XML_CATALOG_FILES.  An empty initial value prevents
     # xmllint and xsltproc from looking in /etc/xml/catalog.
-    export XML_CATALOG_FILES
+    export XML_CATALOG_FILES=''
     if [ -z "$XML_CATALOG_FILES" ]; then XML_CATALOG_FILES=" "; fi
     addEnvHooks "$hostOffset" addXMLCatalogs
 fi