From f315ca6a601e77220323bff4ac7782b54c862a0c Mon Sep 17 00:00:00 2001
From: Milan Crha <mcrha@redhat.com>
Date: Tue, 30 Oct 2018 15:50:58 +0100
Subject: [PATCH] Make sure intltool-merge cache is created only once

Similar to https://gitlab.gnome.org/GNOME/evolution/issues/196
when intltool-merge is called in parallel, it could either rewrite
the ongoing attempt to build it or use an incomplete data, which
results in broken output files (.desktop, .metainfo and so on).
This change ensures the intltool-merge cache is created only once
and any other requests which would use it will wait until it's created.
---
 cmake/modules/FindIntltool.cmake | 11 ++++++++++-
 1 file changed, 10 insertions(+), 1 deletion(-)

diff --git a/cmake/modules/FindIntltool.cmake b/cmake/modules/FindIntltool.cmake
index 2cda2549eb..8e223e9d7f 100644
--- a/cmake/modules/FindIntltool.cmake
+++ b/cmake/modules/FindIntltool.cmake
@@ -176,9 +176,18 @@ macro(intltool_merge _in_filename _out_filename)
 			DEPENDS ${_in}
 		)
 	else(_has_no_translations)
+		if(NOT TARGET intltool-merge-cache)
+			add_custom_command(OUTPUT ${CMAKE_BINARY_DIR}/po/.intltool-merge-cache
+				COMMAND ${INTLTOOL_MERGE} ${_args} --quiet --cache="${CMAKE_BINARY_DIR}/po/.intltool-merge-cache" "${GETTEXT_PO_DIR}" "${_in}" "${_out}"
+				DEPENDS ${_in}
+			)
+			add_custom_target(intltool-merge-cache ALL
+				DEPENDS ${CMAKE_BINARY_DIR}/po/.intltool-merge-cache)
+		endif(NOT TARGET intltool-merge-cache)
+
 		add_custom_command(OUTPUT ${_out}
 			COMMAND ${INTLTOOL_MERGE} ${_args} --quiet --cache="${CMAKE_BINARY_DIR}/po/.intltool-merge-cache" "${GETTEXT_PO_DIR}" "${_in}" "${_out}"
-			DEPENDS ${_in}
+			DEPENDS ${_in} intltool-merge-cache
 		)
 	endif(_has_no_translations)
 endmacro(intltool_merge)
-- 
2.18.1