From 72a2f922393f8029b658fffe3c5a2e3e2c81ac1d Mon Sep 17 00:00:00 2001
From: Kornel Benko <kornel@lyx.org>
Date: Sat, 9 Jun 2018 23:59:47 +0200
Subject: [PATCH] Cmake build: Simplify use of qt5 modules

According to this page:
	http://doc.qt.io/qt-5/cmake-manual.html
the way to replace use of qt5_use_modules() for module "_mod" and target "_target"
is to use
	1.) cmake_minimum_required(VERSION 3.1.0)
	2.) find_package(Qt5${_mod} CONFIG REQUIRED)
	3.) target_link_libraries(${_target} Qt5::${_mod})
The last one sets all reguired libraries, compile flags and needed includes for the ${_target}
---
 CMakeLists.txt | 27 ++++++++++-----------------
 1 file changed, 10 insertions(+), 17 deletions(-)

diff --git a/CMakeLists.txt b/CMakeLists.txt
index 8403934eb4..410f0af683 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -4,7 +4,7 @@
 # Copyright (c) 2006-2011 Peter Kümmel, <syntheticpp@gmx.net>
 # Copyright (c) 2008-2011 Kornel Benko, <Kornel.Benko@berlin.de>
 
-cmake_minimum_required(VERSION 2.6.4)
+cmake_minimum_required(VERSION 3.1.0)
 
 set(LYX_PROJECT LyX)
 
@@ -48,6 +48,7 @@ if(COMMAND cmake_policy)
 		cmake_policy(SET CMP0043 NEW)
 	endif()
 	cmake_policy(SET CMP0020 NEW)
+        cmake_policy(SET CMP0075 OLD)
 endif()
 
 set(CMAKE_ALLOW_LOOSE_LOOP_CONSTRUCTS true)
@@ -622,7 +623,7 @@ endif()
 set(min_qt5_version "5.6")
 if(LYX_USE_QT MATCHES "AUTO")
 	# try qt5 first
-	find_package(Qt5Core QUIET)
+	find_package(Qt5Core CONFIG QUIET)
 	if(Qt5Core_FOUND)
 		set(LYX_USE_QT "QT5" CACHE STRING "Valid qt version" FORCE)
 		message(STATUS "Qt5Core_VERSION = ${Qt5Core_VERSION}")
@@ -638,14 +639,14 @@ if(LYX_USE_QT MATCHES "AUTO")
 endif()
 if(LYX_USE_QT MATCHES "QT5")
 	# set QPA_XCB if QT uses X11
-	find_package(Qt5Core REQUIRED)
+	find_package(Qt5Core CONFIG REQUIRED)
 	if (Qt5Core_FOUND)
-		find_package(Qt5Widgets REQUIRED)
+		find_package(Qt5Widgets CONFIG REQUIRED)
 		if(APPLE)
-			find_package(Qt5MacExtras REQUIRED)
+			find_package(Qt5MacExtras CONFIG REQUIRED)
 		endif()
-		find_package(Qt5X11Extras QUIET)
-		find_package(Qt5WinExtras QUIET)
+		find_package(Qt5X11Extras CONFIG QUIET)
+		find_package(Qt5WinExtras CONFIG QUIET)
 		set(QTVERSION ${Qt5Core_VERSION})
 		if (QTVERSION VERSION_LESS ${min_qt5_version})
 			message(STATUS "QTVERSION = \"${QTVERSION}\"")
@@ -658,17 +659,9 @@ if(LYX_USE_QT MATCHES "QT5")
 			#message(FATAL_ERROR "Wrong Qt-Version")
 		endif()
 		macro (qt_use_modules lyxtarget)
-			if (Qt5_POSITION_INDEPENDENT_CODE
-				AND (CMAKE_VERSION VERSION_LESS 2.8.12
-				AND (NOT CMAKE_CXX_COMPILER_ID STREQUAL "GNU"
-				    OR CMAKE_CXX_COMPILER_VERSION VERSION_LESS 5.0)))
-				set_property(TARGET ${lyxtarget} PROPERTY POSITION_INDEPENDENT_CODE ${Qt5_POSITION_INDEPENDENT_CODE})
-			endif()
 			foreach (_tg ${ARGN})
-				find_package(Qt5${_tg} REQUIRED)
-				include_directories(${Qt5${_tg}_INCLUDE_DIRS})
-				set_property(TARGET ${lyxtarget} APPEND PROPERTY COMPILE_DEFINITIONS ${Qt5${_tg}_COMPILE_DEFINITIONS})
-				target_link_libraries(${lyxtarget} ${Qt5${_tg}_LIBRARIES})
+				find_package(Qt5${_tg} CONFIG REQUIRED)
+				target_link_libraries(${lyxtarget} Qt5::${_tg})
 			endforeach()
 		endmacro()
 		macro (qt_add_resources)