From 7ddd9b0ed78f71a8ee0d1c115f44f765133d0f4e Mon Sep 17 00:00:00 2001
From: Achim Gsell <achim.gsell@psi.ch>
Date: Thu, 22 Apr 2021 09:51:19 +0200
Subject: [PATCH] modulecmd: bugfix in initializing env. variable needed for
 overlays.

- if we switch from a Pmodules version without overlay support to a
  Pmodule version with, some environment variables must be initialzed.
---
 Pmodules/modulecmd.bash.in | 22 ++++++++++++++++++++++
 1 file changed, 22 insertions(+)

diff --git a/Pmodules/modulecmd.bash.in b/Pmodules/modulecmd.bash.in
index 020f225..297a87b 100644
--- a/Pmodules/modulecmd.bash.in
+++ b/Pmodules/modulecmd.bash.in
@@ -2608,8 +2608,30 @@ if [[ -z "${Subcommands[${subcommand}]}" ]]; then
 	std::die 1 "${CMD}: unknown sub-command -- ${subcommand}"
 fi
 
+_init_overlay_map() {
+	local overlay
+	for overlay in "${!Overlays[@]}"; do
+		local group
+		for group in ${UsedGroups//:/ }; do
+			local dir="${overlay}/${group}/${PMODULES_MODULEFILES_DIR}"
+			if [[ -d "${dir}" ]]; then
+				MapDirsToOverlays[${dir}]=${overlay}
+			fi
+		done
+	done
+}
+
 if [[ -n ${PMODULES_ENV} ]]; then
 	eval "$("${base64}" -d <<< "${PMODULES_ENV}" 2>/dev/null)"
+	# if we load a Pmodules version with overlay support,
+	# PMODULES_OVERLAYS might not be set. Since libmodules.tcl
+	# reads PMODULES_ENV we have to save the environment.
+	if [[ -z "${PMODULES_OVERLAYS}" ]]; then
+		declare -g PMODULES_OVERLAYS="${PMODULES_ROOT}"
+		declare -Ag Overlays=([${PMODULES_ROOT}]="0")
+		_init_overlay_map
+		save_env
+	fi
 else
 	pmodules_init
 fi