diff --git a/src/gpg-error-config-head.in b/src/gpg-error-config-head.in
index 1c50fa0..c6219f2 100644
--- a/src/gpg-error-config-head.in
+++ b/src/gpg-error-config-head.in
@@ -1,17 +1,17 @@
 #!/bin/sh
 # Copyright (C) 1999, 2002, 2003 Free Software Foundation, Inc.
 #
 # This file is free software; as a special exception the author gives
 # unlimited permission to copy and/or distribute it, with or without
 # modifications, as long as this notice is preserved.
 #
 # This file is distributed in the hope that it will be useful, but
 # WITHOUT ANY WARRANTY, to the extent permitted by law; without even the
 # implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
 # SPDX-License-Identifier: FSFULLR
 
 prefix=@prefix@
 datarootdir=@datarootdir@
 datadir=@datadir@
-PKG_CONFIG_PATH="${datadir}/pkgconfig"
+PKG_CONFIG_PATH="$PKG_CONFIG_PATH${PKG_CONFIG_PATH:+:}${datadir}/pkgconfig"
 #