Add ios_arm64e Kotlin/Native compilation target

[Oskar Wirga (oskarwirga)]

Wires the iOS arm64e target (Pointer Authentication Code, FEAT_PAuth) end-to-end through target registration, toolchain configuration, gradle DSL, source-set hierarchy, test infrastructure, and platform libraries.

Produces Mach-O arm64e framework binaries with __auth_got / auth-bind chained fixups, ARM64_RELOC_AUTHENTICATED_POINTER relocations, and full ptrauth-* LLVM function attributes from the bundled kotlin/llvm-19-apple toolchain.

Layer breakdown

• Target registration: KonanTarget.IOS_ARM64E plus predefinedTargets, HostManager.appleTargets, supportsIosCrashLog.
• Toolchain config (konan.properties): arm64e-apple-ios triple, apple-a12 CPU, +pauth/+v8.3a features, linker flags, SDK paths.
• Compiler build tooling (runtime/build.gradle.kts): TARGET_OS_* defines extended to cover IOS_ARM64E in the same branch as IOS_ARM64. The fixBrokenMacroExpansionInXcode15_3 logic was previously in ExecClang.kt and is now in the runtime build script.
• ObjC export (InfoPListBuilder.kt): UIRequiredDeviceCapabilities emitted for arm64e frameworks.
• Apple SDK / framework (AppleSdk.kt, XCFrameworkTask.kt, FatFrameworkTask.kt): arm64e Xcode arch mapped to IOS_ARM64E; appleArchitecture distinguishes arm64 from arm64e via a new AppleArchitecture.ARM64E enum value; IPHONE_DEVICE and FatFrameworkTask.supportedTargets extended.
• Gradle DSL (KotlinTargetContainerWithPresetFunctions.kt, KotlinHierarchyBuilder.kt + Impl): iosArm64e() factory overloads (5) and withIosArm64e() hierarchy filter.
• Commonizer (PlatformWidthIndex.kt): IOS_ARM64E mapped to LONG (same width class as IOS_ARM64).
• Test infrastructure (SettingsExecutor, TestProcessSettings, AbstractNativeCInteropTest, kotlin-test-native-xctest, XCTestExecutor, FirebaseCloudXCTestExecutor): SDK mapping to iphoneos, cinterop golden-file mapping, XCTest framework copy task wired with iosArm64e().

Behavioral change

AppleSdk.kt previously mapped the Xcode-requested arch "arm64e" to KonanTarget.IOS_ARM64 - an Xcode pipeline requesting arm64e silently produced an arm64 binary. The mapping now splits:
"arm64" -> KonanTarget.IOS_ARM64
"arm64e" -> KonanTarget.IOS_ARM64E
Callers that depended on the silent downgrade must now explicitly request arm64 in Xcode. The prior behavior was an unintended footgun.

Carried workaround: libunwind.h in darwin.def

kotlin-native/platformLibs/src/platform/ios/darwin.def temporarily drops libunwind.h from its headers = ... list. Apple's <libunwind.h> declares fields such as unw_word_t reg[34] using __ptrauth qualifiers (specifically ptrauth_restricted_intptr_qualifier, which Apple's downstream clang accepts on plain integer types). Kotlin's bundled LLVM 19 (kotlin/llvm-19-apple) does not yet recognise that qualifier, so cinterop fails to parse the header on every ios target - not just arm64e. Removal condition: cherry-pick the qualifier from Apple-LLVM 26.4+ into kotlin/llvm-19-apple, then revert this hunk.

Dependency: kotlin/llvm-19-apple FunctionSpecialization fix ----------------------------------------------------------- This commit deliberately does NOT include the
StripDirectCallPtrauthBundlesPass workaround that was carried during local bring-up. The workaround masked an LLVM 19 IR-verifier failure: FunctionSpecializationPass devirtualized an indirect call whose body carried a ptrauth operand bundle, producing a direct call that still carried the bundle - which LLVM rejects as "Direct call cannot have a ptrauth bundle". Concrete reproducer: K/N's CallInitGlobalPossiblyLock runtime helper, cloned as @CallInitGlobalPossiblyLock.specialized.1.

The proper fix is in upstream LLVM (FunctionSpecialization.cpp strips ptrauth bundles from devirtualized calls before IPSCCP propagates the constant). That fix MUST be cherry-picked into kotlin/llvm-19-apple and the K/N LLVM dependency rolled forward before this commit will produce a working ios_arm64e build - without it, compiling any arm64e Kotlin program will abort at the verifier when the runtime gets linked.

Bootstrap integration note

The KonanTarget.IOS_ARM64E references in runtime/build.gradle.kts and native/kotlin-test-native-xctest/build.gradle.kts compile against the bootstrap kotlin-native-utils classpath, not the in-tree :native:kotlin-native-utils source. Until bootstrap is bumped to a kotlin-native-utils that exports KonanTarget.IOS_ARM64E, those compiles fail with "Unresolved reference: IOS_ARM64E". The standard workflow is to publish an interim bootstrap first.

Verification baseline

Verified during the original bring-up against JetBrains/kotlin f95cb2f with the StripDirectCallPtrauthBundlesPass workaround in place. Outcomes were:

• :kotlin-native:ios_arm64eCrossDist - PASS (2m54s)
• :kotlin-native:platformLibs:ios_arm64eInstall - PASS (1m33s)
• konanc hello.kt -target ios_arm64e -produce framework - PASS; Mach-O 64-bit arm64e, 344 ARM64_RELOC_AUTHENTICATED_POINTER relocations, 85 PAC instructions (blraaz, braaz, paci, autia, ...), __DATA_CONST __auth_got auth-bind rows for every imported symbol.

This rebased version (against current master, without the StripDirectCallPtrauthBundlesPass workaround) has not been re-verified end-to-end because verification requires kotlin/llvm-19-apple to ship the FunctionSpecialization fix first. The Kotlin-side change set is unchanged in intent; only the target file for the Xcode15.3 macro- expansion workaround shifted from ExecClang.kt to
runtime/build.gradle.kts to track the upstream code move.

[kotlin-safemerge]

Code Owners

Rule	Owners	Approval
/​kotlin-​native/​, /​native/​	kotlin-native mMaxy projedi anton-bannykh sbogolepov DmT021 haitaka glukianets azakharenko homuroll SvyatoslavScherbina	❌ UNASSIGNED
/​kotlin-​native/​konan/​konan.​properties	kotlin-build-infrastructure goodwinnk Badya 4u7 tbogdanova CristianGM SmialyKot ozzush kbrgnj	❌ UNASSIGNED
**.​gradle.​kts	sellmair kotlin-build-infrastructure goodwinnk Badya 4u7 tbogdanova CristianGM SmialyKot ozzush kbrgnj	❌ UNASSIGNED
/​libraries/​tools/​kotlin-​gradle-​plugin-​api/​, /​libraries/​tools/​kotlin-​gradle-​plugin/​	kotlin-build-tools AYastrebov Egorand Tapchicoma antohaby Herudaio atyrin CherepanovAleksei rbbozkurt shinkai-tester viakunin adam-enko	❌ UNASSIGNED
/​native/​commonizer/​	kotlin-frontend ligee bnorm mglukhikh KvanTTT cypressious demiurg906 FenstonSingel agamzikova GrigoriiSolnyshkin Aleksandra-Arsenteva	❌ UNASSIGNED
/​native/​native.​tests/​	kotlin-common-backend vsukharev kunyavskiy ivandev0 AnzhelaSukhanova mcpiroman ddolovov mpiekutowski kotlin-native mMaxy projedi anton-bannykh sbogolepov DmT021 haitaka glukianets azakharenko homuroll SvyatoslavScherbina	❌ UNASSIGNED

[Anton Bannykh (anton-bannykh)]

Link to the kotlinlang slack thread.

Also from there:

• draft PR for Kotlin LLVM 19 fork
• draft PR for Kotlin LLVM 21 fork
• upstream LLVM