Simplify CMake build system now that our minimum is 3.20

[jkoritzinsky]

There's a few simplifications we can do now that our minimum CMake version is 3.20 on all platforms:

• Remove the _obj suffix on our CMake targets and remove the "interface" targets now that target_link_libraries can link to object libraries. #92787
• Remove the polyfills used with older CMake versions in functions.cmake
• Remove the add_linker_flag function and instead use target_link_options #92843
• Remove our conditional setting of CMake policies for policies that are now always available.
• Enable CMake policy CMP0117 and update the corresponding compile options throughout the repo. #94354 : PR Remove Explicit Deletion of CMake /GR Flag as 3.20's *CMP0117* by Default Doesn't Add It #96814
• Enable CMake policy CMP0092 and update the corresponding compile options throughout the repo. #96815 : PR Enable CMake Flag -W3 as New CMP0092 no Longer Does it Implicitly #97053
• Use CMake's support to set up IPO optimizations: https://cmake.org/cmake/help/latest/policy/CMP0069.html, https://cmake.org/cmake/help/latest/module/CheckIPOSupported.html#module:CheckIPOSupported
• Use CMake's support to set up PIE options: https://cmake.org/cmake/help/latest/policy/CMP0083.html, https://cmake.org/cmake/help/latest/module/CheckPIESupported.html#module:CheckPIESupported
• Use the FindPython3 CMake module instead of the deprecated FindPythonInterp module. The deprecated module is being removed in newer versions of CMake.
• Remove any CMake version checks that check for versions less than 3.20
• Use Improvements in CMake Generator Expressions to Simplify our Build System's ones #93370
• Investigate if we can simplify the build configuration for Apple Silicon using CMake's support that was added in CMake 3.19
• Set CMP0112 to the NEW behavior and fix any target dependency issues. #97113
• Add CMake presets for common build command line settings (like our standard Debug/Checked/Release options) to help enable better IDE integration and simplify our build process a little. (We can only use features available in version 1 or 2 of the presets format).
• Use CMake's improved support for cross-compiling to Android to simplify our Android and Linux-Bionic build processes.
• Use the CMAKE_<LANG>_BYTE_ORDER setting instead of manually detecting endianness or using the TestBigEndian module (currently used by Mono) #97423 : PR Change the now Deprecated TEST_BIG_ENDIAN to CMAKE_C_BYTE_ORDER #97426
• Use the -S and -B Options on the CMake Command Line to Specify Source and Build Directories Instead of Moving with pushd #93702

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Issue Details

---

There's a few simplifications we can do now that our minimum CMake version is 3.20 on all platforms:

• Remove the _obj suffix on our CMake targets and remove the "interface" targets now that target_link_libraries can link to object libraries.
• Remove the polyfills used with older CMake versions in functions.cmake
• Remove the add_linker_flag function and instead use target_link_options
• Remove our conditional setting of CMake policies for policies that are now always available.
• Enable CMake policy CMP0117 and update the corresponding compile options throughout the repo.
• Enable CMake policy CMP0092 and update the corresponding compile options throughout the repo.
• Use CMake's support to set up IPO optimizations: https://cmake.org/cmake/help/latest/policy/CMP0069.html, https://cmake.org/cmake/help/latest/module/CheckIPOSupported.html#module:CheckIPOSupported
• Use CMake's support to set up PIE options: https://cmake.org/cmake/help/latest/policy/CMP0083.html, https://cmake.org/cmake/help/latest/module/CheckPIESupported.html#module:CheckPIESupported
• Use the FindPython3 CMake module instead of the deprecated FindPythonInterp module. The deprecated module is being removed in newer versions of CMake.
• Remove any CMake version checks that check for versions less than 3.20
• Use improvements in CMake generator expressions to simplify our CMake generator expressions (there are many cases where we can simplify expressions like $<OR:$<CONFIG:X>,$<CONFIG:Y>>:-flag> to $<CONFIG:X,Y>)
• Investigate if we can simplify the build configuration for Apple Silicon using CMake's support that was added in CMake 3.19
• Set CMP0112 to the NEW behavior and fix any target dependency issues.
• Add CMake presets for common build command line settings (like our standard Debug/Checked/Release options) to help enable better IDE integration and simplify our build process a little. (We can only use features available in version 1 or 2 of the presets format).
• Use CMake's improved support for cross-compiling to Android to simplify our Android and Linux-Bionic build processes.
• Use the CMAKE_<LANG>_BYTE_ORDER setting instead of manually detecting endianness or using the TestBigEndian module (currently used by Mono)
• Use the -S and -B options on the CMake command line to specify source and build directories instead of using pushd to be in specific working directories.

Author:	jkoritzinsky
Assignees:	-
Labels:	area-Infrastructure
Milestone:	Future