CMake: Grab bag of tiny refactors and improvements

CMakeLists.txt

@@ -59,7 +59,7 @@ if( GODOT_ENABLE_TESTING )
     add_subdirectory( test )
 endif()
 
-# If this is the top level CMakeLists.txt, Generators which honor the
-# USE_FOLDERS flag will organize godot-cpp targets under the subfolder
-# 'godot-cpp'. This is enable by default from CMake version 3.26
+#[[ If this is the top level CMakeLists.txt, Generators which honor the
+USE_FOLDERS flag will organize godot-cpp targets under the subfolder
+'godot-cpp'. This is enable by default from CMake version 3.26 ]]
 set_property(GLOBAL PROPERTY USE_FOLDERS ON)

cmake/android.cmake

@@ -25,10 +25,21 @@ Android platforms.
 There is further information and examples in the doc/cmake.rst file.
 
 ]=======================================================================]
+
+#[============================[ Android Options ]============================]
 function( android_options )
-    # Android Options
+    #[[ The options present in the SCons build shown below are managed by
+    toolchain files, further information can be found in doc/cmake.rst
+
+    android_api_level : Target Android API level.
+        Default = 21
+
+    ANDROID_HOME : Path to your Android SDK installation.
+        Default = os.environ.get("ANDROID_HOME", os.environ.get("ANDROID_SDK_ROOT")
+    ]]
 endfunction()
 
+#[===========================[ Target Generation ]===========================]
 function( android_generate )
     target_compile_definitions(${TARGET_NAME}
             PUBLIC

cmake/common_compiler_flags.cmake

@@ -7,6 +7,16 @@ configuration. It includes flags like optimization levels, warnings, and
 features. For target platform specific flags look to each of the
 ``cmake/<platform>.cmake`` files.
 
+The default compile and link options CMake adds can be found in the
+platform modules_. When a project is created it initializes its variables from
+the ``CMAKE_*`` values. The cleanest way I have found to alter these defaults
+is the use of the ``CMAKE_PROJECT_<PROJECT-NAME>_INCLUDE`` as demonstrated by
+the emsdkHack.cmake to overcome the limitation on shared library creation.
+
+So far the emsdkHack is the only modification to the defaults we have made.
+
+.. _modules: https://github.com/Kitware/CMake/blob/master/Modules/Platform/
+
 ]=======================================================================]
 
 #[[ Compiler Configuration, not to be confused with build targets ]]
@@ -19,12 +29,13 @@ set( IS_GNU "$<CXX_COMPILER_ID:GNU>" )
 set( IS_MSVC "$<CXX_COMPILER_ID:MSVC>" )
 set( NOT_MSVC "$<NOT:$<CXX_COMPILER_ID:MSVC>>" )
 
-set( GNU_LT_V8 "$<VERSION_LESS:$<CXX_COMPILER_VERSION>,8>" )
-set( GNU_GE_V9 "$<VERSION_GREATER_EQUAL:$<CXX_COMPILER_VERSION>,9>" )
-set( GNU_GT_V11 "$<VERSION_GREATER_EQUAL:$<CXX_COMPILER_VERSION>,11>" )
-set( GNU_LT_V11 "$<VERSION_LESS:$<CXX_COMPILER_VERSION>,11>" )
-set( GNU_GE_V12 "$<VERSION_GREATER_EQUAL:$<CXX_COMPILER_VERSION>,12>" )
+set( LT_V8  "$<VERSION_LESS:$<CXX_COMPILER_VERSION>,8>" )
+set( GE_V9  "$<VERSION_GREATER_EQUAL:$<CXX_COMPILER_VERSION>,9>" )
+set( GT_V11 "$<VERSION_GREATER_EQUAL:$<CXX_COMPILER_VERSION>,11>" )
+set( LT_V11 "$<VERSION_LESS:$<CXX_COMPILER_VERSION>,11>" )
+set( GE_V12 "$<VERSION_GREATER_EQUAL:$<CXX_COMPILER_VERSION>,12>" )
 
+#[===========================[ compiler_detection ]===========================]
 #[[ Check for clang-cl with MSVC frontend
 The compiler is tested and set when the project command is called.
 The variable CXX_COMPILER_FRONTEND_VARIANT was introduced in 3.14
@@ -44,21 +55,19 @@ function( compiler_detection )
     endif ()
 endfunction(  )
 
+#[=========================[ common_compiler_flags ]=========================]
+#[[ This function assumes it is being called from within one of the platform
+generate functions, with all the variables from lower scopes defined. ]]
 function( common_compiler_flags )
 
-    target_compile_features(${TARGET_NAME}
-            PUBLIC
-            cxx_std_17
-    )
-
     # These compiler options reflect what is in godot/SConstruct.
     target_compile_options( ${TARGET_NAME}
+        # The public flag tells CMake that the following options are transient,
+        #and will propagate to consumers.
         PUBLIC
             # Disable exception handling. Godot doesn't use exceptions anywhere, and this
             # saves around 20% of binary size and very significant build time.
-            $<${DISABLE_EXCEPTIONS}:
-                $<${NOT_MSVC}:-fno-exceptions>
-            >
+            $<${DISABLE_EXCEPTIONS}:$<${NOT_MSVC}:-fno-exceptions>>
 
             # Enabling Debug Symbols
             $<${DEBUG_SYMBOLS}:
@@ -70,20 +79,19 @@ function( common_compiler_flags )
                 >
             >
 
-            $<${IS_DEV_BUILD}:
-                $<${NOT_MSVC}:-fno-omit-frame-pointer -O0>
-            >
+            $<${IS_DEV_BUILD}:$<${NOT_MSVC}:-fno-omit-frame-pointer -O0>>
 
-            $<${HOT_RELOAD}:
-                $<${IS_GNU}:-fno-gnu-unique>
-            >
+            $<${HOT_RELOAD}:$<${IS_GNU}:-fno-gnu-unique>>
+
+        # Warnings below, these do not need to propagate to consumers.
+        PRIVATE
 
         # MSVC only
         $<${IS_MSVC}:
             # /MP isn't valid for clang-cl with msvc frontend
             $<$<CXX_COMPILER_ID:MSVC>:/MP${PROC_N}>
-            /W4
 
+            /W4      # Warning level 4 (informational) warnings that aren't off by default.
             # Disable warnings which we don't plan to fix.
             /wd4100  # C4100 (unreferenced formal parameter): Doesn't play nice with polymorphism.
             /wd4127  # C4127 (conditional expression is constant)
@@ -124,21 +132,22 @@ function( common_compiler_flags )
             -Wplacement-new=1
             -Wshadow-local
             -Wstringop-overflow=4
+        >
 
-            # Bogus warning fixed in 8+.
-            $<${GNU_LT_V8}:-Wno-strict-overflow>
+        # Bogus warning fixed in 8+.
+        $<${IS_GNU}:$<${LT_V8}:-Wno-strict-overflow>>
 
-            $<${GNU_GE_V9}:-Wattribute-alias=2>
+        $<${IS_GNU}:$<${GE_V9}:-Wattribute-alias=2>>
 
-            # Broke on MethodBind templates before GCC 11.
-            $<${GNU_GT_V11}:-Wlogical-op>
+        # Broke on MethodBind templates before GCC 11.
+        $<${IS_GNU}:$<${GT_V11}:-Wlogical-op>>
 
-            # Regression in GCC 9/10, spams so much in our variadic templates that we need to outright disable it.
-            $<${GNU_LT_V11}:-Wno-type-limits>
+        # Regression in GCC 9/10, spams so much in our variadic templates that we need to outright disable it.
+        $<${IS_GNU}:$<${LT_V11}:-Wno-type-limits>>
+
+        # False positives in our error macros, see GH-58747.
+        $<${IS_GNU}:$<${GE_V12}:-Wno-return-type>>
 
-            # False positives in our error macros, see GH-58747.
-            $<${GNU_GE_V12}:-Wno-return-type>
-        >
     )
 
     target_compile_definitions(${TARGET_NAME}
@@ -158,13 +167,11 @@ function( common_compiler_flags )
     )
 
     target_link_options( ${TARGET_NAME}
-        PUBLIC
-            $<${IS_MSVC}:
-                /WX             # treat link warnings as errors.
-                /MANIFEST:NO    # We dont need a manifest
-            >
+        PRIVATE
+            $<${IS_MSVC}:/WX /MANIFEST:NO>
+            # /WX             # treat link warnings as errors.
+            # /MANIFEST:NO    # We dont need a manifest
 
-            $<${DEBUG_SYMBOLS}:$<${IS_MSVC}:/DEBUG:FULL>>
             $<$<NOT:${DEBUG_SYMBOLS}>:
                 $<${IS_GNU}:-s>
                 $<${IS_CLANG}:-s>

cmake/emsdkHack.cmake

@@ -27,11 +27,11 @@ if( EMSCRIPTEN )
     set_property(GLOBAL PROPERTY TARGET_SUPPORTS_SHARED_LIBS TRUE)
     set(CMAKE_SHARED_LIBRARY_CREATE_C_FLAGS "-sSIDE_MODULE=1")
     set(CMAKE_SHARED_LIBRARY_CREATE_CXX_FLAGS "-sSIDE_MODULE=1")
-    set(CMAKE_SHARED_LIBRARY_SUFFIX) # remove the suffix from the shared lib
+    set(CMAKE_SHARED_LIBRARY_SUFFIX ".wasm") # SCons uses .wasm as a suffix
     set(CMAKE_STRIP FALSE)  # used by default in pybind11 on .so modules
 
     # The Emscripten toolchain sets the default value for EMSCRIPTEN_SYSTEM_PROCESSOR to x86
-    # and CMAKE_SYSTEM_PROCESSOR to this value. I don't want that.
+    # and copies that to CMAKE_SYSTEM_PROCESSOR. We dont want that.
     set(CMAKE_SYSTEM_PROCESSOR "wasm32" )
     # the above prevents the need for logic like:
     #if( ${CMAKE_SYSTEM_NAME} STREQUAL Emscripten )

cmake/godotcpp.cmake

@@ -11,18 +11,12 @@ This if statement simply silences that warning.
 if( CMAKE_C_COMPILER )
 endif ()
 
-#[=======================================================================[.rst:
-Include Platform Files
-----------------------
-
-Because these files are included into the top level CMakelists.txt before the
+#[[ Include Platform Files
+Because these files are included into the top level CMakeLists.txt before the
 project directive, it means that
 
-* ``CMAKE_CURRENT_SOURCE_DIR`` is the location of godot-cpp's CMakeLists.txt
-* ``CMAKE_SOURCE_DIR`` is the location where any prior ``project(...)``
-  directive was
-
-]=======================================================================]
+CMAKE_CURRENT_SOURCE_DIR is the location of godot-cpp's CMakeLists.txt
+CMAKE_SOURCE_DIR is the location where any prior project() directive was ]]
 include( ${CMAKE_CURRENT_SOURCE_DIR}/cmake/common_compiler_flags.cmake)
 include( ${CMAKE_CURRENT_SOURCE_DIR}/cmake/android.cmake)
 include( ${CMAKE_CURRENT_SOURCE_DIR}/cmake/ios.cmake)
@@ -43,7 +37,8 @@ set( PLATFORM_LIST linux macos windows android ios web )
 # List of known architectures
 set( ARCH_LIST universal x86_32 x86_64 arm32 arm64 rv64 ppc32 ppc64 wasm32 )
 
-# Function to map processors to known architectures
+#[=============================[ godot_arch_map ]=============================]
+#[[ Function to map CMAKE_SYSTEM_PROCESSOR names to godot arch equivalents ]]
 function( godot_arch_map ALIAS PROC )
     string( TOLOWER "${PROC}" PROC )
 
@@ -157,7 +152,7 @@ function( godotcpp_options )
     windows_options()
 endfunction()
 
-# Function to configure and generate the targets
+#[===========================[ Target Generation ]===========================]
 function( godotcpp_generate )
     #[[ Multi-Threaded MSVC Compilation
     When using the MSVC compiler the build command -j <n> only specifies
@@ -240,16 +235,15 @@ function( godotcpp_generate )
 
     ### Platform is derived from the toolchain target
     # See GeneratorExpressions PLATFORM_ID and CMAKE_SYSTEM_NAME
-    set( SYSTEM_NAME
-            $<$<PLATFORM_ID:Android>:android>
-            $<$<PLATFORM_ID:iOS>:ios>
-            $<$<PLATFORM_ID:Linux>:linux>
-            $<$<PLATFORM_ID:Darwin>:macos>
-            $<$<PLATFORM_ID:Emscripten>:web>
-            $<$<PLATFORM_ID:Windows>:windows>
-            $<$<PLATFORM_ID:Msys>:windows>
+    string( APPEND SYSTEM_NAME
+            "$<$<PLATFORM_ID:Android>:android.${ANDROID_ABI}>"
+            "$<$<PLATFORM_ID:iOS>:ios>"
+            "$<$<PLATFORM_ID:Linux>:linux>"
+            "$<$<PLATFORM_ID:Darwin>:macos>"
+            "$<$<PLATFORM_ID:Emscripten>:web>"
+            "$<$<PLATFORM_ID:Windows>:windows>"
+            "$<$<PLATFORM_ID:Msys>:windows>"
     )
-    string(REPLACE ";" "" SYSTEM_NAME "${SYSTEM_NAME}")
 
     ### Use the arch from the toolchain if it isn't set manually
     if( GODOT_ARCH )
@@ -272,8 +266,6 @@ function( godotcpp_generate )
         message( WARNING "=> GODOT_DEV_BUILD implies a Debug-like build but CMAKE_BUILD_TYPE is '${CMAKE_BUILD_TYPE}'")
     endif ()
     set( IS_DEV_BUILD "$<BOOL:${GODOT_DEV_BUILD}>")
-    # The .dev portion of the name if GODOT_DEV_BUILD is true.
-    set( DEV_TAG "$<${IS_DEV_BUILD}:.dev>" )
 
     ### Define our godot-cpp library targets
     foreach ( TARGET_ALIAS template_debug template_release editor )
@@ -283,6 +275,17 @@ function( godotcpp_generate )
         set( DEBUG_FEATURES "$<NOT:$<STREQUAL:${TARGET_ALIAS},template_release>>" )
         set( HOT_RELOAD "$<IF:${HOT_RELOAD-UNSET},${DEBUG_FEATURES},$<BOOL:${GODOT_USE_HOT_RELOAD}>>" )
 
+        # Suffix
+        string( JOIN "" GODOT_SUFFIX
+                "$<1:.${SYSTEM_NAME}>"
+                "$<1:.${TARGET_ALIAS}>"
+                "$<${IS_DEV_BUILD}:.dev>"
+                "$<$<STREQUAL:${GODOT_PRECISION},double>:.double>"
+                "$<1:.${SYSTEM_ARCH}>"
+                # missing IOS_SIMULATOR
+                # missing THREADS
+        )
+
         # the godot-cpp.* library targets
         add_library( ${TARGET_NAME} STATIC EXCLUDE_FROM_ALL )
         add_library( godot-cpp::${TARGET_ALIAS} ALIAS ${TARGET_NAME} )
@@ -308,17 +311,21 @@ function( godotcpp_generate )
                 CXX_VISIBILITY_PRESET ${GODOT_SYMBOL_VISIBILITY}
 
                 COMPILE_WARNING_AS_ERROR ${GODOT_WARNING_AS_ERROR}
+
                 POSITION_INDEPENDENT_CODE ON
-                BUILD_RPATH_USE_ORIGIN ON
+                INTERFACE_POSITION_INDEPENDENT_CODE ON
+
+                PREFIX      "lib"
+                OUTPUT_NAME "${PROJECT_NAME}${GODOT_SUFFIX}"
 
-                PREFIX lib
-                OUTPUT_NAME "${PROJECT_NAME}.${SYSTEM_NAME}.${TARGET_ALIAS}${DEV_TAG}.${SYSTEM_ARCH}"
                 ARCHIVE_OUTPUT_DIRECTORY "$<1:${CMAKE_BINARY_DIR}/bin>"
 
                 # Things that are handy to know for dependent targets
-                GODOT_PLATFORM "${SYSTEM_NAME}"
-                GODOT_TARGET "${TARGET_ALIAS}"
-                GODOT_ARCH "${SYSTEM_ARCH}"
+                GODOT_PLATFORM  "${SYSTEM_NAME}"
+                GODOT_TARGET    "${TARGET_ALIAS}"
+                GODOT_ARCH      "${SYSTEM_ARCH}"
+                GODOT_PRECISION "${GODOT_PRECISION}"
+                GODOT_SUFFIX    "${GODOT_SUFFIX}"
 
                 # Some IDE's respect this property to logically group targets
                 FOLDER "godot-cpp"

cmake/ios.cmake

@@ -6,10 +6,20 @@ This file contains functions for options and configuration for targeting the
 Ios platform
 
 ]=======================================================================]
+
+#[==============================[ iOS Options ]==============================]
 function(ios_options)
-    # iOS options
+#    TODO "ios_simulator", "Target iOS Simulator", False
+#    TODO "ios_min_version", "Target minimum iphoneos/iphonesimulator version", "12.0"
+#    TODO "IOS_TOOLCHAIN_PATH",
+#        "Path to iOS toolchain",
+#        "/Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain",
+#    TODO "IOS_SDK_PATH", "Path to the iOS SDK", ""
+#
+#    TODO if has_ios_osxcross(): "ios_triple", "Triple for ios toolchain", ""
 endfunction()
 
+#[===========================[ Target Generation ]===========================]
 function(ios_generate)
     target_compile_definitions(${TARGET_NAME}
             PUBLIC

cmake/linux.cmake

@@ -6,10 +6,18 @@ This file contains functions for options and configuration for targeting the
 Linux platform
 
 ]=======================================================================]
+
+#[=============================[ Linux Options ]=============================]
 function( linux_options )
-    # Linux Options
+    #[[ The options present in the SCons build shown below are managed by
+    toolchain files, further information can be found in doc/cmake.rst
+
+    use_llvm : Use the LLVM compiler
+        Default: False
+]]
 endfunction()
 
+#[===========================[ Target Generation ]===========================]
 function( linux_generate )
     target_compile_definitions( ${TARGET_NAME}
             PUBLIC

cmake/macos.cmake

@@ -7,22 +7,26 @@ MacOS platform
 
 ]=======================================================================]
 
-# Find Requirements
-IF(APPLE)
+#[===========================[ Find Dependencies ]===========================]
+# APPLE is set to True when the target system is an Apple platform
+# (macOS, iOS, tvOS, visionOS or watchOS).
+if( APPLE )
     set( CMAKE_OSX_SYSROOT $ENV{SDKROOT} )
     find_library( COCOA_LIBRARY REQUIRED
         NAMES Cocoa
         PATHS ${CMAKE_OSX_SYSROOT}/System/Library
         PATH_SUFFIXES Frameworks
-        NO_DEFAULT_PATH)
-ENDIF (APPLE)
-
+        NO_DEFAULT_PATH )
+endif( APPLE )
 
+#[=============================[ MacOS Options ]=============================]
 function( macos_options )
-    # macos options here
+    # TODO "macos_deployment_target" "macOS deployment target" "default"
+    # TODO "macos_sdk_path" "macOS SDK path" ""
+    # TODO if has_osxcross(): "osxcross_sdk" "OSXCross SDK version" "darwin16"
 endfunction()
 
-
+#[===========================[ Target Generation ]===========================]
 function( macos_generate )
 
     # OSX_ARCHITECTURES does not support generator expressions.
@@ -36,7 +40,9 @@ function( macos_generate )
     set_target_properties( ${TARGET_NAME}
             PROPERTIES
 
+            # Specify multiple architectures for universal builds
             OSX_ARCHITECTURES "${OSX_ARCH}"
+            GODOT_ARCH ${SYSTEM_ARCH}
     )
 
     target_compile_definitions(${TARGET_NAME}