[clang] [clang][driver][darwin] Prefer DarwinSDKInfo for platform identification and compatibility over the -isysroot path (PR #176541)

[Cyndy Ishida via cfe-commits]

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+{"DisplayName":"Simulator - visionOS 1.0","DefaultProperties":{"LLVM_TARGET_TRIPLE_SUFFIX":"-simulator","DEFAULT_COMPILER":"com.apple.compilers.llvm.clang.1_0","AD_HOC_CODE_SIGNING_ALLOWED":"YES","TEST_LIBRARY_SEARCH_PATHS":"$(inherited) $(PLATFORM_DIR)\/Developer\/usr\/lib","DEPLOYMENT_TARGET_SUGGESTED_VALUES":["1.0"],"TEST_FRAMEWORK_SEARCH_PATHS":"$(inherited) $(PLATFORM_DIR)\/Developer\/Library\/Frameworks $(SDKROOT)\/Developer\/Library\/Frameworks","DEAD_CODE_STRIPPING":"YES","CODE_SIGN_IDENTITY":"-","CODE_SIGNING_REQUIRED":"YES","TAPI_VERIFY_MODE":"Pedantic","SUPPORTED_DEVICE_FAMILIES":"7","ENTITLEMENTS_DESTINATION":"__entitlements","PLATFORM_NAME":"xrsimulator","ENTITLEMENTS_REQUIRED":"YES","CODE_SIGN_ENTITLEMENTS":"","XROS_DEPLOYMENT_TARGET":"1.0","RESOURCES_PLATFORM_NAME":"xros","TAPI_USE_SRCROOT":"YES"},"MinimalDisplayName":"Simulator - 1.0","Version":"1.0","IsBaseSDK":"YES","SupportedTargets":{"xrsimulator":{"LLVMTargetTripleVendor":"apple","DeploymentTargetSettingName":"XROS_DEPLOYMENT_TARGET","PlatformFamilyDisplayName":"visionOS","Archs":["arm64","x86_64"],"LLVMTargetTripleEnvironment":"simulator","ClangRuntimeLibraryPlatformName":"xrossim","MaximumDeploymentTarget":"1.0.99","BuildVersionPlatformID":"12","DefaultDeploymentTarget":"1.0","LLVMTargetTripleSys":"xros","DeviceFamilies":[{"Identifier":"7","Name":"vision","DisplayName":"Apple Vision"}],"MinimumDeploymentTarget":"1.0","SwiftConcurrencyMinimumDeploymentTarget":"1.0","SwiftOSRuntimeMinimumDeploymentTarget":"1.0","RecommendedDeploymentTarget":"1.0","PlatformFamilyName":"xrOS","SystemPrefix":"","ValidDeploymentTargets":["1.0"]}},"PropertyConditionFallbackNames":["embeddedsimulator"],"VersionMap":{"xrOS_iOS":{"1.0":"17.1"},"iOS_visionOS":{"17.1":"1.0"},"iOS_xrOS":{"17.1":"1.0"},"visionOS_iOS":{"1.0":"17.1"}},"DefaultDeploymentTarget":"1.0","MaximumDeploymentTarget":"1.0.99","DebuggerOptions":{"SupportsViewDebugging":"YES"},"CanonicalName":"xrsimulator1.0","CustomProperties":{"CLANG_ENABLE_EXPLICIT_MODULES":"NO"}}
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cyndyishida wrote:

Do we actually need all of these fields for the tests? For example `"CustomProperties":{"CLANG_ENABLE_EXPLICIT_MODULES":"NO"` is purely an xcode setting.

https://github.com/llvm/llvm-project/pull/176541