Modernize CMake build system (#1434)

These changes modernize the CMake build system to (hopefully) match newer best practices

* Library linking is simpler and more automatic because of using imported targets
* Multi-configuration builds should be supported (Ninja Multi-Config, Visual Studio, etc. generators)
* Clean up build options using cmake_dependent_option
* Let CMake do its job in more cases, like finding the math/dl libraries and detecting and enabling LTO support
* Remove platform-specific kludges like the Fedora/flatpak LTO workaround and a bunch of Windows stuff
* Simplify Windows static builds
* Consistent formatting

1 files changed, 33 insertions, 64 deletions

diff --git a/src/frontend/qt_sdl/CMakeLists.txt b/src/frontend/qt_sdl/CMakeLists.txt
index ec88026..6f95cc5 100644
--- a/src/frontend/qt_sdl/CMakeLists.txt
+++ b/src/frontend/qt_sdl/CMakeLists.txt
@@ -1,10 +1,12 @@
-project(qt_sdl)
+include(CMakeDependentOption)
 
-SET(SOURCES_QT_SDL
+include(FixInterfaceIncludes)
+
+set(SOURCES_QT_SDL
     main.cpp
     main_shaders.h
     CheatsDialog.cpp
-	Config.cpp
+    Config.cpp
     EmuSettingsDialog.cpp
     PowerManagement/PowerManagementDialog.cpp
     PowerManagement/resources/battery.qrc
@@ -28,9 +30,9 @@ SET(SOURCES_QT_SDL
     font.h
     Platform.cpp
     QPathInput.h
-	ROMManager.cpp
-	SaveManager.cpp
-    
+    ROMManager.cpp
+    SaveManager.cpp
+
     ArchiveUtil.h
     ArchiveUtil.cpp
 
@@ -40,7 +42,7 @@ SET(SOURCES_QT_SDL
     ../mic_blow.h
 
     ${CMAKE_SOURCE_DIR}/res/melon.qrc
-)
+    )
 
 if (APPLE)
     option(USE_QT6 "Build using Qt 6 instead of 5" ON)
@@ -54,27 +56,9 @@ if (WIN32)
 endif()
 
 if (USE_QT6)
-    if (BUILD_STATIC AND QT6_STATIC_DIR)
-        set(QT6_STATIC_BASE ${QT6_STATIC_DIR}/lib/cmake/Qt6)
-        set(Qt6_DIR ${QT6_STATIC_BASE})
-        set(Qt6Core_DIR ${QT6_STATIC_BASE}Core)
-        set(Qt6Gui_DIR ${QT6_STATIC_BASE}Gui)
-        set(Qt6Widgets_DIR ${QT6_STATIC_BASE}Widgets)
-        set(Qt6Network_DIR ${QT6_STATIC_BASE}Network)
-        set(Qt6OpenGL_DIR ${QT6_STATIC_BASE}OpenGL)
-        set(Qt6OpenGLWidgets_DIR ${QT6_STATIC_BASE}OpenGLWidgets)
-    endif()
     find_package(Qt6 COMPONENTS Core Gui Widgets Network OpenGL OpenGLWidgets REQUIRED)
     set(QT_LINK_LIBS Qt6::Core Qt6::Gui Qt6::Widgets Qt6::Network Qt6::OpenGL Qt6::OpenGLWidgets)
 else()
-    if (BUILD_STATIC AND QT5_STATIC_DIR)
-        set(QT5_STATIC_BASE ${QT5_STATIC_DIR}/lib/cmake/Qt5)
-        set(Qt5_DIR ${QT5_STATIC_BASE})
-        set(Qt5Core_DIR ${QT5_STATIC_BASE}Core)
-        set(Qt5Gui_DIR ${QT5_STATIC_BASE}Gui)
-        set(Qt5Widgets_DIR ${QT5_STATIC_BASE}Widgets)
-        set(Qt5Network_DIR ${QT5_STATIC_BASE}Network)
-    endif()
     find_package(Qt5 COMPONENTS Core Gui Widgets Network REQUIRED)
     set(QT_LINK_LIBS Qt5::Core Qt5::Gui Qt5::Widgets Qt5::Network)
 endif()
@@ -83,63 +67,48 @@ set(CMAKE_AUTOMOC ON)
 set(CMAKE_AUTOUIC ON)
 set(CMAKE_AUTORCC ON)
 
+if (BUILD_STATIC)
+    list(APPEND PKG_CONFIG_EXECUTABLE "--static")
+endif()
+
 find_package(Threads REQUIRED)
 find_package(PkgConfig REQUIRED)
-find_package(Iconv REQUIRED)
-pkg_check_modules(SDL2 REQUIRED sdl2)
-pkg_check_modules(SLIRP REQUIRED slirp)
-pkg_check_modules(LIBARCHIVE REQUIRED libarchive)
-add_compile_definitions(ARCHIVE_SUPPORT_ENABLED)
-
-if (WIN32 AND (CMAKE_BUILD_TYPE STREQUAL Release))
-    add_executable(melonDS WIN32 ${SOURCES_QT_SDL})
-else()
-    add_executable(melonDS ${SOURCES_QT_SDL})
-endif()
+pkg_check_modules(SDL2 REQUIRED IMPORTED_TARGET sdl2)
+pkg_check_modules(Slirp REQUIRED IMPORTED_TARGET slirp)
+pkg_check_modules(LibArchive REQUIRED IMPORTED_TARGET libarchive)
 
-target_link_libraries(melonDS ${CMAKE_THREAD_LIBS_INIT})
+fix_interface_includes(PkgConfig::SDL2 PkgConfig::Slirp PkgConfig::LibArchive)
 
-target_include_directories(melonDS PRIVATE ${SDL2_INCLUDE_DIRS} ${SDL2_PREFIX}/include ${SLIRP_INCLUDE_DIRS} ${LIBARCHIVE_INCLUDE_DIRS})
-target_link_directories(melonDS PRIVATE ${SDL2_LIBRARY_DIRS} ${SLIRP_LIBRARY_DIRS})
-target_link_directories(melonDS PRIVATE ${LIBARCHIVE_LIBRARY_DIRS})
+add_compile_definitions(ARCHIVE_SUPPORT_ENABLED)
 
-target_include_directories(melonDS PUBLIC "${CMAKE_CURRENT_SOURCE_DIR}")
-target_include_directories(melonDS PUBLIC "${CMAKE_CURRENT_SOURCE_DIR}/..")
-target_include_directories(melonDS PUBLIC "${CMAKE_CURRENT_SOURCE_DIR}/../..")
-target_link_libraries(melonDS core)
+add_executable(melonDS ${SOURCES_QT_SDL})
 
 if (BUILD_STATIC)
-    target_link_libraries(melonDS -static ${SDL2_STATIC_LIBRARIES} ${SLIRP_STATIC_LIBRARIES} ${LIBARCHIVE_STATIC_LIBRARIES})
     qt_import_plugins(melonDS INCLUDE Qt::QSvgPlugin)
-else()
-    target_link_libraries(melonDS ${SDL2_LIBRARIES} ${SLIRP_LIBRARIES} ${LIBARCHIVE_LIBRARIES})
+    target_link_options(melonDS PRIVATE -static)
 endif()
 
-if (NOT Iconv_IS_BUILT_IN)
-    target_link_libraries(melonDS ${Iconv_LIBRARIES})
-endif()
+target_include_directories(melonDS PUBLIC "${CMAKE_CURRENT_SOURCE_DIR}")
+target_include_directories(melonDS PUBLIC "${CMAKE_CURRENT_SOURCE_DIR}/..")
+target_include_directories(melonDS PUBLIC "${CMAKE_CURRENT_SOURCE_DIR}/../..")
+target_link_libraries(melonDS PRIVATE core)
+target_link_libraries(melonDS PRIVATE PkgConfig::SDL2 PkgConfig::Slirp PkgConfig::LibArchive)
+target_link_libraries(melonDS PRIVATE ${QT_LINK_LIBS} ${CMAKE_DL_LIBS})
 
 if (UNIX)
     option(PORTABLE "Make a portable build that looks for its configuration in the current directory" OFF)
-    target_link_libraries(melonDS ${QT_LINK_LIBS})
-    if (CMAKE_SYSTEM_NAME STREQUAL "Linux")
-        target_link_libraries(melonDS dl)
-    endif()
 elseif (WIN32)
     option(PORTABLE "Make a portable build that looks for its configuration in the current directory" ON)
+
     configure_file("${CMAKE_SOURCE_DIR}/res/melon.rc.in" "${CMAKE_SOURCE_DIR}/melon.rc")
     target_sources(melonDS PUBLIC "${CMAKE_SOURCE_DIR}/melon.rc")
 
-    target_link_libraries(melonDS comctl32 d2d1 dwrite uxtheme ws2_32 iphlpapi gdi32)
-    if (BUILD_STATIC)
-        target_link_libraries(melonDS imm32 winmm version setupapi -static z zstd ${QT_LINK_LIBS})
-    else()
-        target_link_libraries(melonDS ${QT_LINK_LIBS})
-    endif()
+    target_link_libraries(melonDS PRIVATE ws2_32 iphlpapi)
+    set_target_properties(melonDS PROPERTIES WIN32_EXECUTABLE $<CONFIG:Release>)
 endif()
 
 if (PORTABLE)
-    add_definitions(-DPORTABLE)
+    target_compile_definitions(melonDS PRIVATE PORTABLE)
 endif()
 
 if (APPLE)
@@ -152,7 +121,7 @@ if (APPLE)
         MACOSX_BUNDLE_INFO_PLIST ${CMAKE_SOURCE_DIR}/res/melon.plist.in
         OUTPUT_NAME melonDS
         RESOURCE "${RESOURCE_FILES}")
-	
+
 
     option(MACOS_BUNDLE_LIBS "Bundle libraries with the app on macOS" OFF)
     option(MACOS_BUILD_DMG "Build DMG image of the macOS application bundle" OFF)
@@ -170,8 +139,8 @@ endif()
 if (UNIX AND NOT APPLE)
     foreach(SIZE 16 32 48 64 128 256)
         install(FILES ${CMAKE_SOURCE_DIR}/res/icon/melon_${SIZE}x${SIZE}.png
-                DESTINATION ${CMAKE_INSTALL_PREFIX}/share/icons/hicolor/${SIZE}x${SIZE}/apps
-                RENAME net.kuribo64.melonDS.png)
+            DESTINATION ${CMAKE_INSTALL_PREFIX}/share/icons/hicolor/${SIZE}x${SIZE}/apps
+            RENAME net.kuribo64.melonDS.png)
     endforeach()
 
     install(FILES ${CMAKE_SOURCE_DIR}/res/net.kuribo64.melonDS.desktop DESTINATION ${CMAKE_INSTALL_PREFIX}/share/applications)