Define TARGET_LINUX for Android native builds and preserve Android-specific exclusions

[Copilot]

Android was treated as Linux in managed constants (TargetsLinux) but not consistently in native C/C++ compile-time defines. This change aligns the native side by defining TARGET_LINUX on Android and simplifying call sites that previously special-cased TARGET_ANDROID, while preserving Android-specific exclusions where Linux-only native behavior does not apply.

• Build-definition alignment

  • eng/native/configurecompiler.cmake: Android now emits both TARGET_ANDROID and TARGET_LINUX.
  • src/mono/CMakeLists.txt: Android target setup now sets TARGET_LINUX (alongside existing Android/Bionic defines).

• Conditional cleanup

  • Replaced defined(TARGET_LINUX) || defined(TARGET_ANDROID) with defined(TARGET_LINUX) where behavior is shared.
  • Updated corresponding negated conditions/comments to match the new invariant.
  • Applied across affected native/runtime files (System.Native, CoreCLR minipal/pal/gc, NativeAOT PAL, and related headers).

• Android-specific corrections

  • Restored an explicit !defined(TARGET_ANDROID) exclusion in src/native/corehost/corehost.cpp for static createdump initialization.
  • Excluded Android from CoreCLR GC's Linux NUMA syscall paths in src/coreclr/gc/unix/numasupport.cpp and related call sites in src/coreclr/gc/unix/gcenv.unix.cpp.
  • These exclusions preserve existing Android behavior and avoid widening Linux-only paths through the new TARGET_LINUX define.

// Shared behavior
// Before
#if defined(TARGET_LINUX) || defined(TARGET_ANDROID)

// After
#if defined(TARGET_LINUX)

// Android-specific static host path remains excluded
#if defined(FEATURE_STATIC_HOST) && (defined(TARGET_OSX) || (defined(TARGET_LINUX) && !defined(TARGET_ANDROID))) && !defined(TARGET_X86)

// Android remains excluded from Linux-only NUMA syscall paths
#if defined(TARGET_LINUX) && !defined(TARGET_ANDROID)

[jkotas]

@copilot Are there any TARGET_LINUX uses that need to be modified to exclude TARGET_ANDROID with this change?

[Copilot]

@copilot Are there any TARGET_LINUX uses that need to be modified to exclude TARGET_ANDROID with this change?

I audited the affected native files for this PR and did not find any TARGET_LINUX sites that need an added !TARGET_ANDROID exclusion. The places changed were all previously TARGET_LINUX || TARGET_ANDROID (so behavior stays aligned), and existing Android-specific differences are still explicitly guarded by TARGET_ANDROID where needed.

[Copilot]

Pull request overview

This PR standardizes native build-time OS macros so Android also defines TARGET_LINUX, and then simplifies a set of native #if guards that previously treated Linux and Android as separate-but-equivalent cases.

Changes:

• Define TARGET_LINUX for Android native builds (CoreCLR/native CMake + Mono CMake).
• Collapse redundant defined(TARGET_LINUX) || defined(TARGET_ANDROID) checks to defined(TARGET_LINUX) in several native components.
• Update related #else / #endif comments and negated conditions to match the new invariant.

Reviewed changes

Copilot reviewed 10 out of 10 changed files in this pull request and generated no comments.

Show a summary per file

File	Description
eng/native/configurecompiler.cmake	Ensures Android emits TARGET_LINUX (via Linux target path) while still defining TARGET_ANDROID.
src/mono/CMakeLists.txt	Sets TARGET_LINUX for Android in Mono’s CMake configuration.
src/native/libs/System.Native/pal_time.c	Uses TARGET_LINUX as the single guard for the Linux/Android boot-time clock path.
src/native/libs/System.Native/pal_io.c	Simplifies Linux/Android filesystem-type guarding to TARGET_LINUX.
src/coreclr/pal/src/misc/cgroup.cpp	Collapses Linux/Android cgroup implementation guard to TARGET_LINUX and updates guard comments.
src/coreclr/gc/unix/cgroup.cpp	Collapses Linux/Android GC cgroup implementation guard to TARGET_LINUX and updates guard comments.
src/coreclr/nativeaot/Runtime/unix/PalUnix.cpp	Simplifies Linux/Android TLS-key guarding to TARGET_LINUX (with corresponding negated guard update).
src/coreclr/nativeaot/Runtime/unix/cgroupcpu.cpp	Collapses Linux/Android NativeAOT cgroup CPU guard to TARGET_LINUX and updates guard comments.
src/coreclr/minipal/Unix/doublemapping.cpp	Uses TARGET_LINUX as the single guard for the Linux/Android memfd_create path.
src/coreclr/inc/crosscomp.h	Simplifies Linux/Android DAC mutex sizing guard to TARGET_LINUX.

[jkotas]

@copilot Build break

FAILED: Corehost.Static/singlefilehost
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vm/eventing/eventpipe/CMakeFiles/eventpipe_gen_objs.dir/eventpipe/dotnetruntime.cpp.o vm/eventing/eventpipe/CMakeFiles/eventpipe_gen_objs.dir/eventpipe/dotnetruntimerundown.cpp.o vm/eventing/eventpipe/CMakeFiles/eventpipe_gen_objs.dir/eventpipe/dotnetruntimestress.cpp.o vm/eventing/eventpipe/CMakeFiles/eventpipe_gen_objs.dir/eventpipe/dotnetruntimeprivate.cpp.o vm/eventing/eventpipe/CMakeFiles/eventpipe_objs.dir/Unity/unity_0_cxx.cxx.o containers/CMakeFiles/dn-containers.dir/dn-allocator.c.o containers/CMakeFiles/dn-containers.dir/dn-fwd-list.c.o containers/CMakeFiles/dn-containers.dir/dn-list.c.o containers/CMakeFiles/dn-containers.dir/dn-queue.c.o containers/CMakeFiles/dn-containers.dir/dn-umap.c.o containers/CMakeFiles/dn-containers.dir/dn-vector.c.o containers/CMakeFiles/dn-containers.dir/dn-simdhash.c.o containers/CMakeFiles/dn-containers.dir/dn-simdhash-string-ptr.c.o containers/CMakeFiles/dn-containers.dir/dn-simdhash-u32-ptr.c.o 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Corehost.Static/CMakeFiles/singlefilehost.dir/__w/1/s/src/native/corehost/apphost/bundle_marker.cpp.o Corehost.Static/CMakeFiles/singlefilehost.dir/hostfxr_resolver.cpp.o Corehost.Static/CMakeFiles/singlefilehost.dir/hostpolicy_resolver.cpp.o Corehost.Static/CMakeFiles/singlefilehost.dir/__w/1/s/src/native/corehost/hostpolicy/static/coreclr_resolver.cpp.o Corehost.Static/CMakeFiles/singlefilehost.dir/__w/1/s/src/native/corehost/fxr_resolver.cpp.o Corehost.Static/CMakeFiles/singlefilehost.dir/__w/1/s/src/native/corehost/corehost.cpp.o Corehost.Static/CMakeFiles/singlefilehost.dir/__w/1/s/src/native/corehost/fxr/command_line.cpp.o Corehost.Static/CMakeFiles/singlefilehost.dir/__w/1/s/src/native/corehost/fxr/corehost_init.cpp.o Corehost.Static/CMakeFiles/singlefilehost.dir/__w/1/s/src/native/corehost/fxr/hostfxr.cpp.o Corehost.Static/CMakeFiles/singlefilehost.dir/__w/1/s/src/native/corehost/fxr/fx_muxer.cpp.o 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Corehost.Static/CMakeFiles/singlefilehost.dir/__w/1/s/src/native/corehost/hostpolicy/deps_entry.cpp.o Corehost.Static/CMakeFiles/singlefilehost.dir/__w/1/s/src/native/corehost/hostpolicy/deps_format.cpp.o Corehost.Static/CMakeFiles/singlefilehost.dir/__w/1/s/src/native/corehost/hostpolicy/deps_resolver.cpp.o Corehost.Static/CMakeFiles/singlefilehost.dir/__w/1/s/src/native/corehost/hostpolicy/hostpolicy_context.cpp.o Corehost.Static/CMakeFiles/singlefilehost.dir/__w/1/s/src/native/corehost/hostpolicy/hostpolicy.cpp.o Corehost.Static/CMakeFiles/singlefilehost.dir/__w/1/s/src/native/corehost/hostpolicy/hostpolicy_init.cpp.o Corehost.Static/CMakeFiles/singlefilehost.dir/__w/1/s/src/native/corehost/hostpolicy/shared_store.cpp.o Corehost.Static/CMakeFiles/singlefilehost.dir/__w/1/s/src/native/corehost/hostpolicy/version.cpp.o Corehost.Static/CMakeFiles/singlefilehost.dir/__w/1/s/src/native/corehost/bundle/dir_utils.cpp.o Corehost.Static/CMakeFiles/singlefilehost.dir/__w/1/s/src/native/corehost/bundle/extractor.cpp.o Corehost.Static/CMakeFiles/singlefilehost.dir/__w/1/s/src/native/corehost/bundle/file_entry.cpp.o Corehost.Static/CMakeFiles/singlefilehost.dir/__w/1/s/src/native/corehost/bundle/manifest.cpp.o Corehost.Static/CMakeFiles/singlefilehost.dir/__w/1/s/src/native/corehost/bundle/runner.cpp.o Corehost.Static/CMakeFiles/singlefilehost.dir/__w/1/s/src/native/corehost/json_parser.cpp.o Corehost.Static/CMakeFiles/singlefilehost.dir/__w/1/s/src/native/corehost/host_startup_info.cpp.o Corehost.Static/CMakeFiles/singlefilehost.dir/__w/1/s/src/native/corehost/roll_forward_option.cpp.o Corehost.Static/CMakeFiles/singlefilehost.dir/__w/1/s/src/native/corehost/fx_definition.cpp.o Corehost.Static/CMakeFiles/singlefilehost.dir/__w/1/s/src/native/corehost/fx_reference.cpp.o Corehost.Static/CMakeFiles/singlefilehost.dir/__w/1/s/src/native/corehost/version_compatibility_range.cpp.o Corehost.Static/CMakeFiles/singlefilehost.dir/__w/1/s/src/native/corehost/runtime_config.cpp.o Corehost.Static/CMakeFiles/singlefilehost.dir/__w/1/s/src/native/corehost/bundle/info.cpp.o Corehost.Static/CMakeFiles/singlefilehost.dir/__w/1/s/src/native/corehost/bundle/reader.cpp.o Corehost.Static/CMakeFiles/singlefilehost.dir/__w/1/s/src/native/corehost/bundle/header.cpp.o -o Corehost.Static/singlefilehost dlls/mscoree/coreclr/libcoreclr_static.a libs-native/System.Globalization.Native/libSystem.Globalization.Native.a libs-native/System.IO.Compression.Native/libSystem.IO.Compression.Native.a libs-native/System.Native/libSystem.Native.a libs-native/System.Security.Cryptography.Native.Android/libSystem.Security.Cryptography.Native.Android.a pal/src/libcoreclrpal_dac.a debug/dbgutil/libdbgutil.a nativeresources/libnativeresourcestring.a -lz -Xlinker --push-state -Xlinker --whole-archive debug/runtimeinfo/libruntimeinfo.a -Xlinker --pop-state Corehost.Static/hostmisc/libhostmisc.a nativeresources/libnativeresourcestring.a minipal/Unix/libcoreclrminipal.a shared_minipal/libminipal.a pal/src/eventprovider/dummyprovider/libeventprovider.a -llog _deps/zstd-build/lib/libzstd.a _deps/brotli-build/libbrotlienc.a _deps/brotli-build/libbrotlidec.a _deps/brotli-build/libbrotlicommon.a -ldl -latomic -lm && cd /__w/1/s/artifacts/obj/coreclr/android.arm.Release/Corehost.Static && sh -c "echo Stripping symbols from $(basename '/__w/1/s/artifacts/obj/coreclr/android.arm.Release/Corehost.Static/singlefilehost') into $(basename '/__w/1/s/artifacts/obj/coreclr/android.arm.Release/Corehost.Static/singlefilehost.dbg')" && /usr/local/android-sdk/ndk/27.2.12479018/toolchains/llvm/prebuilt/linux-x86_64/bin/llvm-objcopy --only-keep-debug /__w/1/s/artifacts/obj/coreclr/android.arm.Release/Corehost.Static/singlefilehost /__w/1/s/artifacts/obj/coreclr/android.arm.Release/Corehost.Static/singlefilehost.dbg && /usr/local/android-sdk/ndk/27.2.12479018/toolchains/llvm/prebuilt/linux-x86_64/bin/llvm-objcopy --strip-debug --strip-unneeded /__w/1/s/artifacts/obj/coreclr/android.arm.Release/Corehost.Static/singlefilehost && /usr/local/android-sdk/ndk/27.2.12479018/toolchains/llvm/prebuilt/linux-x86_64/bin/llvm-objcopy --add-gnu-debuglink=/__w/1/s/artifacts/obj/coreclr/android.arm.Release/Corehost.Static/singlefilehost.dbg /__w/1/s/artifacts/obj/coreclr/android.arm.Release/Corehost.Static/singlefilehost
ld.lld: error: undefined symbol: initialize_static_createdump()

referenced by corehost.cpp:125 (/__w/1/s/src/native/corehost/corehost.cpp:125)
Corehost.Static/CMakeFiles/singlefilehost.dir/__w/1/s/src/native/corehost/corehost.cpp.o:(exe_start(int, char const**))

[Copilot]

@copilot Build break

FAILED: Corehost.Static/singlefilehost
...

Fixed in f9e3214. corehost.cpp's static createdump initialization was unintentionally widened to Android by the new TARGET_LINUX define, so I restored the Android exclusion on that path. I also validated it with ./src/native/corehost/build.sh -os android -arch arm -c Release -ninja.

[jkotas]

@copilot Tests are failing on Android

                 06-01 07:15:54.842  3495  3514 D DOTNET  : Calling coreclr_initialize
[07:16:04] dbug: Executing command: '/datadisks/disk1/work/A34008FE/p/microsoft.dotnet.xharness.cli/11.0.0-prerelease.26204.1/runtimes/any/native/adb/linux/adb -s emulator-5556 bugreport /datadisks/disk1/work/A34008FE/w/A89F0902/uploads/adb-bugreport-net.dot.System.Runtime.Tests.zip'
[07:18:13] info: Wrote ADB bugreport to /datadisks/disk1/work/A34008FE/w/A89F0902/uploads/adb-bugreport-net.dot.System.Runtime.Tests.zip
[07:18:13] info: <<XHARNESS_RESULT_START>>

Please double check that there are no other ifdefs condition that need adjusting for this change.

[Copilot]

@copilot Tests are failing on Android

                 06-01 07:15:54.842  3495  3514 D DOTNET  : Calling coreclr_initialize

...

Fixed in 2d0161a. Android was entering CoreCLR's Linux NUMA path after TARGET_LINUX started being defined there, and coreclr_initialize then hit seccomp-blocked get_mempolicy/mbind syscalls. I excluded Android from the NUMA-only guards in src/coreclr/gc/unix/numasupport.cpp and the related GC call sites in gcenv.unix.cpp.

Validated with:

• ./src/coreclr/build-runtime.sh x64 -release -component runtime -ninja -numproc 4
• ./build.sh clr.runtime -os android -arch arm64 -c Release -ninja

AI-generated comment posted by Copilot.

[jkotas]

TARGET_LINUX and TARGET_ANDROID

CLR_CMAKE_TARGET_LINUX is defined on Android
TARGET_LINUX is defined on Android in CoreLib
TARGET_LINUX is not defined on Android for C/C++ code <- this is inconsistency that I got confused by and that I am trying to fix

TARGET_OSX and TARGET_IOS

I do not think that this is same relationship as Linux vs. Android. In RID graph:

• Android imports Linux
• iOS and OSX are unrelated

[Copilot]

Pull request overview

Copilot reviewed 13 out of 13 changed files in this pull request and generated no new comments.

[jkotas]

@VSadov Noticed while reviewing #128606

[VSadov]

@VSadov Noticed while reviewing #128606

I noticed as well, but was not sure if native/managed difference was intentional.

There is also something called “bionic”. It is defined for android and not used much. I suspect there is a conceptual distinction, but practically it is not very different.

[jkotas]

There is also something called “bionic”

bionic is name libc used by Android. It is sibling of glibc and musl.

Android in our build system means Android apps. it implies bionic libc, crypto via Java interop, and disables use of OS features that are blocked for Android apps.

[VSadov]

LGTM!

[jkotas]

/ba-g infrastructure timeout