From 9158fe0e3e71712e205bd190299ea0ad525aa32a Mon Sep 17 00:00:00 2001
From: Armin Novak <armin.novak@thincast.com>
Date: Tue, 31 Jan 2017 16:52:20 +0100
Subject: [PATCH] Support old CMake versions without TIMESTAMP #3727

---
 cmake/today.cmake | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/cmake/today.cmake b/cmake/today.cmake
index d2f5eaa87..659e5eced 100644
--- a/cmake/today.cmake
+++ b/cmake/today.cmake
@@ -6,6 +6,13 @@ MACRO (TODAY RESULT)
     if (DEFINED ENV{SOURCE_DATE_EPOCH} AND NOT WIN32)
         EXECUTE_PROCESS(COMMAND "date" "-u" "-d" "@$ENV{SOURCE_DATE_EPOCH}" "+%Y-%m-%d"
                         OUTPUT_VARIABLE ${RESULT} OUTPUT_STRIP_TRAILING_WHITESPACE)
+    elseif(CMAKE_VERSION VERSION_LESS "2.8.11")
+	if (WIN32)
+		message(FATAL_ERROR "Your CMake version is too old. Please update to a more recent version >= 2.8.11")
+	else()
+		EXECUTE_PROCESS(COMMAND "date" "-u" "+%Y-%m-%d"
+                        OUTPUT_VARIABLE ${RESULT} OUTPUT_STRIP_TRAILING_WHITESPACE)
+	endif()
     else()
         STRING(TIMESTAMP ${RESULT} "%Y-%m-%d" UTC)
     endif()