cmake: Adjust macOS SDK detection #11893
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jcm93
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| endif() | ||
| message(DEBUG "macOS SDK Path: ${_obs_macos_sdk_path}") | ||
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| string(REGEX MATCH ".+/MacOSX.platform/Developer/SDKs/MacOSX([0-9]+\\.[0-9])+\\.sdk$" _ ${_obs_macos_sdk_path}) |
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Will xcrun always yield the numeric variant of the SDK? By default they are just symlinks to MacOSX.sdk anyway.
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The xcrun man page doesn't specifically indicate that it provides the fully resolved versioned symlink path always.
Adding a file(REAL_PATH ...) call to resolve the path seems like probably a good idea just in case.
We could also alternately use the --show-sdk-platform-version command provided by xcrun instead of --show-sdk-path, and short circuit the regex matching that we perform to determine the version. Though that regex specifically matches on Xcode paths and not Xcode Command Line Tools paths, so we might have to do something else in that case to detect that the user is specifically using Xcode and not just the command line tools.
edit: As you indicated, the xcrun-derived path is indeed a symlink; and we want the symlink path in this case rather than the absolute path.
I doubt that the existing versioning system in Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs is going anywhere, but it might be slightly more robust/future-proof to use --show-sdk-platform-version and then a separate check to verify that the user has Xcode and not just the CLT.
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We could do something like separately run xcrun --find xcodebuild to detect Xcode.
Description
Adjust the macOS CMake initialization logic to use
xcrunto derive our SDK version information, rather than relying on the presence of${CMAKE_OSX_SYSROOT}.Motivation and Context
CMake 4.0.0 (currently in the release candidate phase) breaks OBS configuration/generation on macOS. This is because CMake 4.0.0 no longer defines
CMAKE_OSX_SYSROOTby default for macOS builds, which we currently rely on to make sure the user has an SDK supported by OBS.This CMake change was apparently made because specifying
CMAKE_OSX_SYSROOTseems to translate under the hood to passing-isysrootto the compiler, which apparently had some undesired impacts in some situations (further context here and here). Letting the compiler wrapper figure out its sysroot on its own seems to now be the preferred pattern.As we would still like to check what SDK version the user has installed, we can just derive it ourselves using
xcrunto populate a variable with the user's environment's currently configured SDK path. This way we can make sure that the user has an SDK version we support, while still letting CMake not define a sysroot.How Has This Been Tested?
Installed CMake 4.0.0 rc1 and configured/generated/built OBS successfully; also made sure configuration/generation/building proceeded successfully on CMake 3.31.4.
Types of changes
Checklist: