Blazor AoT on linux-arm64 emcc compiler errors .NET 10

[LeviateK]

Description

Attempting to leverage arm64 build agents for Blazor AoT builds to see if they are faster and get the following errors - same config works on linux_x64:

emcc : error : '/mnt/vss/_work/_tool/dotnet/packs/Microsoft.NET.Runtime.Emscripten.3.1.56.Node.linux-arm64/10.0.0/tools/bin/node /mnt/vss/_work/tool/dotnet/packs/Microsoft.NET.Runtime.Emscripten.3.1.56.Sdk.linux-arm64/10.0.0/tools/emscripten/src/compiler.mjs /tmp/tmp3udm74h.json --symbols-only' failed (returned 127)

/mnt/vss/_work/_tool/dotnet/packs/Microsoft.NET.Runtime.WebAssembly.Sdk/10.0.0/Sdk/BrowserWasmApp.targets(522,5): error MSB3073: The command "emcc "@/mnt/vss/_work/_tool/dotnet/packs/Microsoft.NETCore.App.Runtime.Mono.browser-wasm/10.0.0/runtimes/browser-wasm/native/src/emcc-default.rsp" -msimd128 "@/mnt/vss/_work/_tool/dotnet/packs/Microsoft.NETCore.App.Runtime.Mono.browser-wasm/10.0.0/runtimes/browser-wasm/native/src/emcc-link.rsp" "@/mnt/vss/_work/1/s/Client/obj/Debug/net10.0/wasm/for-build/emcc-link.rsp"" exited with code 1.

I see a couple similar issues, but I do not use Sentry nor do I have Heap Size set in csproj.

Reproduction Steps

Build Pipeline Steps - first two tasks complete, 3rd is where the failures happen. Does not make it to the publish step yet on linux-arm64, only x64.

- task: UseDotNet@2
  displayName: Download .NET
  inputs:
    useGlobalJson: true

- task: DotNetCoreCLI@2
  displayName: Install WebAssembly workload for AoT
  inputs:
    command: 'custom'
    custom: 'workload'
    arguments: 'restore'

- task: DotNetCoreCLI@2
  condition: succeeded()
  displayName: Build Projects
  inputs:
    command: 'build'
    projects: '**/*.csproj'
    feedsToUse: 'select'

- task: DotNetCoreCLI@2
  displayName: Publish Server ZIP
  condition: succeeded()
  inputs:
    command: 'publish'
    publishWebProjects: false
    projects: '**/Server.csproj'
    arguments: '-r linux-x64 --configuration $(BuildConfiguration) --output $(build.artifactstagingdirectory)'

Expected behavior

Build completes without errors

Linking with emcc with -O0. This may take a while ...
/opt/hostedtoolcache/dotnet/packs/Microsoft.NET.Runtime.Emscripten.3.1.56.Sdk.linux-x64/10.0.0/tools/bin/clang --version
/opt/hostedtoolcache/dotnet/packs/Microsoft.NET.Runtime.Emscripten.3.1.56.Node.linux-x64/10.0.0/tools/bin/node /opt/hostedtoolcache/dotnet/packs/Microsoft.NET.Runtime.Emscripten.3.1.56.Sdk.linux-x64/10.0.0/tools/emscripten/src/compiler.mjs /tmp/tmp3riwfcxt.json --symbols-only
/opt/hostedtoolcache/dotnet/packs/Microsoft.NET.Runtime.Emscripten.3.1.56.Sdk.linux-x64/10.0.0/tools/bin/wasm-ld -o /mnt/vss/_work/1/s/Client/obj/Debug/net10.0/wasm/for-build/dotnet.native.wasm /mnt/vss/_work/1/s/Client/obj/Debug/net10.0/wasm/for-build/pinvoke.o /mnt/vss/_work/1/s/Client/obj/Debug/net10.0/wasm/for-build/driver.o /mnt/vss/_work/1/s/Client/obj/Debug/net10.0/wasm/for-build/corebindings.o /mnt/vss/_work/1/s/Client/obj/Debug/net10.0/wasm/for-build/runtime.o /opt/hostedtoolcache/dotnet/packs/Microsoft.NETCore.App.Runtime.Mono.browser-wasm/10.0.0/runtimes/browser-wasm/native/libbrotlicommon.a /opt/hostedtoolcache/dotnet/packs/Microsoft.NETCore.App.Runtime.Mono.browser-wasm/10.0.0/runtimes/browser-wasm/native/libbrotlidec.a /opt/hostedtoolcache/dotnet/packs/Microsoft.NETCore.App.Runtime.Mono.browser-wasm/10.0.0/runtimes/browser-wasm/native/libbrotlienc.a /opt/hostedtoolcache/dotnet/packs/Microsoft.NETCore.App.Runtime.Mono.browser-wasm/10.0.0/runtimes/browser-wasm/native/libicudata.a /opt/hostedtoolcache/dotnet/packs/Microsoft.NETCore.App.Runtime.Mono.browser-wasm/10.0.0/runtimes/browser-wasm/native/libicui18n.a /opt/hostedtoolcache/dotnet/packs/Microsoft.NETCore.App.Runtime.Mono.browser-wasm/10.0.0/runtimes/browser-wasm/native/libicuuc.a /opt/hostedtoolcache/dotnet/packs/Microsoft.NETCore.App.Runtime.Mono.browser-wasm/10.0.0/runtimes/browser-wasm/native/libmono-component-debugger-static.a /opt/hostedtoolcache/dotnet/packs/Microsoft.NETCore.App.Runtime.Mono.browser-wasm/10.0.0/runtimes/browser-wasm/native/libmono-component-diagnostics_tracing-stub-static.a /opt/hostedtoolcache/dotnet/packs/Microsoft.NETCore.App.Runtime.Mono.browser-wasm/10.0.0/runtimes/browser-wasm/native/libmono-component-hot_reload-static.a /opt/hostedtoolcache/dotnet/packs/Microsoft.NETCore.App.Runtime.Mono.browser-wasm/10.0.0/runtimes/browser-wasm/native/libmono-component-marshal-ilgen-stub-static.a /opt/hostedtoolcache/dotnet/packs/Microsoft.NETCore.App.Runtime.Mono.browser-wasm/10.0.0/runtimes/browser-wasm/native/libmono-ee-interp.a /opt/hostedtoolcache/dotnet/packs/Microsoft.NETCore.App.Runtime.Mono.browser-wasm/10.0.0/runtimes/browser-wasm/native/libmono-icall-table.a /opt/hostedtoolcache/dotnet/packs/Microsoft.NETCore.App.Runtime.Mono.browser-wasm/10.0.0/runtimes/browser-wasm/native/libmono-profiler-aot.a /opt/hostedtoolcache/dotnet/packs/Microsoft.NETCore.App.Runtime.Mono.browser-wasm/10.0.0/runtimes/browser-wasm/native/libmono-profiler-browser.a /opt/hostedtoolcache/dotnet/packs/Microsoft.NETCore.App.Runtime.Mono.browser-wasm/10.0.0/runtimes/browser-wasm/native/libmono-profiler-log.a /opt/hostedtoolcache/dotnet/packs/Microsoft.NETCore.App.Runtime.Mono.browser-wasm/10.0.0/runtimes/browser-wasm/native/libmono-wasm-eh-wasm.a /opt/hostedtoolcache/dotnet/packs/Microsoft.NETCore.App.Runtime.Mono.browser-wasm/10.0.0/runtimes/browser-wasm/native/libmono-wasm-simd.a /opt/hostedtoolcache/dotnet/packs/Microsoft.NETCore.App.Runtime.Mono.browser-wasm/10.0.0/runtimes/browser-wasm/native/libmonosgen-2.0.a /opt/hostedtoolcache/dotnet/packs/Microsoft.NETCore.App.Runtime.Mono.browser-wasm/10.0.0/runtimes/browser-wasm/native/libSystem.Globalization.Native.a /opt/hostedtoolcache/dotnet/packs/Microsoft.NETCore.App.Runtime.Mono.browser-wasm/10.0.0/runtimes/browser-wasm/native/libSystem.IO.Compression.Native.a /opt/hostedtoolcache/dotnet/packs/Microsoft.NETCore.App.Runtime.Mono.browser-wasm/10.0.0/runtimes/browser-wasm/native/libSystem.Native.a /opt/hostedtoolcache/dotnet/packs/Microsoft.NETCore.App.Runtime.Mono.browser-wasm/10.0.0/runtimes/browser-wasm/native/libz.a /opt/hostedtoolcache/dotnet/packs/Microsoft.NETCore.App.Runtime.Mono.browser-wasm/10.0.0/runtimes/browser-wasm/native/wasm-bundled-timezones.a -L/opt/hostedtoolcache/dotnet/packs/Microsoft.NET.Runtime.Emscripten.3.1.56.Cache.linux-x64/10.0.0/tools/emscripten/cache/sysroot/lib/wasm32-emscripten -lGL-getprocaddr -lal -lhtml5 -lbulkmemory -lstubs-debug -lc-debug -ldlmalloc -lcompiler_rt-wasm-sjlj -lc++-except -lc++abi-debug-except -lunwind-except -lsockets -mllvm -combiner-global-alias-analysis=false -mllvm -wasm-enable-sjlj -mllvm -disable-lsr -mllvm -wasm-enable-eh -mllvm -exception-model=wasm /tmp/tmp_gz4_cculibemscripten_js_symbols.so --export=free --export=htons --export=malloc --export=sbrk --export=memalign --export=posix_memalign --export=memset --export=ntohs --export=stackAlloc --export=stackRestore --export=stackSave --export=fmod --export=atan2 --export=fma --export=pow --export=fmodf --export=atan2f --export=fmaf --export=powf --export=asin --export=asinh --export=acos --export=acosh --export=atan --export=atanh --export=cbrt --export=cos --export=cosh --export=exp --export=log --export=log2 --export=log10 --export=sin --export=sinh --export=tan --export=tanh --export=asinf --export=asinhf --export=acosf --export=acoshf --export=atanf --export=atanhf --export=cbrtf --export=cosf --export=coshf --export=expf --export=logf --export=log2f --export=log10f --export=sinf --export=sinhf --export=tanf --export=tanhf --export=__cpp_exception --export=emscripten_stack_get_end --export=emscripten_stack_get_free --export=emscripten_stack_get_base --export=emscripten_stack_get_current --export=emscripten_stack_init --export=stackAlloc --export=__funcs_on_exit --export=__trap --export=__cpp_exception --export=__wasm_call_ctors --export=__get_exception_message --export=free --export=stackSave --export=stackRestore --export=__thrown_object_from_unwind_exception --export=__cxa_increment_exception_refcount --export=__cxa_decrement_exception_refcount --export-if-defined=__start_em_asm --export-if-defined=__stop_em_asm --export-if-defined=__start_em_lib_deps --export-if-defined=__stop_em_lib_deps --export-if-defined=__start_em_js --export-if-defined=__stop_em_js --export-if-defined=main --export-if-defined=__main_argc_argv --export-if-defined=fflush --export-table --growable-table -z stack-size=5242880 --max-memory=2147483648 --initial-memory=63963136 --no-entry --stack-first --table-base=1
/opt/hostedtoolcache/dotnet/packs/Microsoft.NET.Runtime.Emscripten.3.1.56.Sdk.linux-x64/10.0.0/tools/bin/llvm-objcopy /mnt/vss/_work/1/s/Client/obj/Debug/net10.0/wasm/for-build/dotnet.native.wasm /mnt/vss/_work/1/s/Client/obj/Debug/net10.0/wasm/for-build/dotnet.native.wasm --remove-section=producers
/opt/hostedtoolcache/dotnet/packs/Microsoft.NET.Runtime.Emscripten.3.1.56.Node.linux-x64/10.0.0/tools/bin/node /opt/hostedtoolcache/dotnet/packs/Microsoft.NET.Runtime.Emscripten.3.1.56.Sdk.linux-x64/10.0.0/tools/emscripten/src/compiler.mjs /tmp/tmpt9u7lg9q.json

Actual behavior

FAILURE

Linking with emcc with -O0. This may take a while ...
/mnt/vss/_work/_tool/dotnet/packs/Microsoft.NET.Runtime.Emscripten.3.1.56.Sdk.linux-arm64/10.0.0/tools/bin/clang --version
/mnt/vss/_work/_tool/dotnet/packs/Microsoft.NET.Runtime.Emscripten.3.1.56.Node.linux-arm64/10.0.0/tools/bin/node /mnt/vss/_work/tool/dotnet/packs/Microsoft.NET.Runtime.Emscripten.3.1.56.Sdk.linux-arm64/10.0.0/tools/emscripten/src/compiler.mjs /tmp/tmp3udm74h.json --symbols-only
/mnt/vss/_work/_tool/dotnet/packs/Microsoft.NET.Runtime.Emscripten.3.1.56.Node.linux-arm64/10.0.0/tools/bin/node: error while loading shared libraries: libatomic.so.1: cannot open shared object file: No such file or directory
##[error]emcc(0,0): Error : '/mnt/vss/_work/_tool/dotnet/packs/Microsoft.NET.Runtime.Emscripten.3.1.56.Node.linux-arm64/10.0.0/tools/bin/node /mnt/vss/_work/tool/dotnet/packs/Microsoft.NET.Runtime.Emscripten.3.1.56.Sdk.linux-arm64/10.0.0/tools/emscripten/src/compiler.mjs /tmp/tmp3udm74h.json --symbols-only' failed (returned 127)
emcc : error : '/mnt/vss/_work/_tool/dotnet/packs/Microsoft.NET.Runtime.Emscripten.3.1.56.Node.linux-arm64/10.0.0/tools/bin/node /mnt/vss/_work/tool/dotnet/packs/Microsoft.NET.Runtime.Emscripten.3.1.56.Sdk.linux-arm64/10.0.0/tools/emscripten/src/compiler.mjs /tmp/tmp3udm74h.json --symbols-only' failed (returned 127)

##[error]/mnt/vss/_work/_tool/dotnet/packs/Microsoft.NET.Runtime.WebAssembly.Sdk/10.0.0/Sdk/BrowserWasmApp.targets(522,5): Error MSB3073: The command "emcc "@/mnt/vss/_work/_tool/dotnet/packs/Microsoft.NETCore.App.Runtime.Mono.browser-wasm/10.0.0/runtimes/browser-wasm/native/src/emcc-default.rsp" -msimd128 "@/mnt/vss/_work/_tool/dotnet/packs/Microsoft.NETCore.App.Runtime.Mono.browser-wasm/10.0.0/runtimes/browser-wasm/native/src/emcc-link.rsp" "@/mnt/vss/_work/1/s/Client/obj/Debug/net10.0/wasm/for-build/emcc-link.rsp"" exited with code 1.
/mnt/vss/_work/_tool/dotnet/packs/Microsoft.NET.Runtime.WebAssembly.Sdk/10.0.0/Sdk/BrowserWasmApp.targets(522,5): error MSB3073: The command "emcc "@/mnt/vss/_work/_tool/dotnet/packs/Microsoft.NETCore.App.Runtime.Mono.browser-wasm/10.0.0/runtimes/browser-wasm/native/src/emcc-default.rsp" -msimd128 "@/mnt/vss/_work/_tool/dotnet/packs/Microsoft.NETCore.App.Runtime.Mono.browser-wasm/10.0.0/runtimes/browser-wasm/native/src/emcc-link.rsp" "@/mnt/vss/_work/1/s/Client/obj/Debug/net10.0/wasm/for-build/emcc-link.rsp"" exited with code 1.

Build FAILED.

Regression?

Unknown - First time trying this

Known Workarounds

x64 build agents do not have this issue.

Configuration

Version: .NET 10
Build Environment: linux-arm64 (Ubuntu 24.04)

Other information

No response

[am11]

error while loading shared libraries: libatomic.so.1: cannot open shared object file: No such file or directory

You are building on Azure DevOps host, which is x64, and running arm node which requires aarch64 libatomic dependency. Try adding:

- script: |
    sudo dpkg --add-architecture arm64
    sudo apt update
    sudo apt install -y libatomic1:arm64
  displayName: 'Obtain node arm64 dependencies'

Secondly, you don't need -r linux-arm64, since the target rid is browser-wasm regardless what the build arch was. So you can always keep host==build by dropping -r linux-arm64. If you are on a real linux-arm64 system (like osx-arm64 running ubuntu with docker --platform=linux/arm64), then the dotnet workload restore will bring in arm64 node/emcc etc. e.g.

FROM mcr.microsoft.com/dotnet/sdk:10.0 AS build

RUN apt-get update && apt-get install -y --no-install-recommends \
    python3 \
    nodejs \
    npm \
    build-essential \
    clang \
    ca-certificates \
    && rm -rf /var/lib/apt/lists/*

WORKDIR /src

RUN dotnet new blazorwasm -n ReproBlazorAot
WORKDIR /src/ReproBlazorAot

RUN dotnet workload restore
RUN dotnet workload install wasm-tools

RUN dotnet publish -c Release \
    -p:RunAOTCompilation=true \
    -p:PublishTrimmed=true \
    --self-contained=false

docker build --platform=linux/arm64 -t blazor-aot-repro --progress=plain .

^ run this on a arm64 host machine (otherwise if host is x64, then docker will inject qemu emulation where dotnet(1) is known to misbehave).

[LeviateK]

Thanks @am11 - the install libataomic1 fixed the build and I removed the -r linux-arm64 flag from the publish and it runs without issue! Any other speed optimization tips? I know AoT is designed to take longer to provide better client-side experience, was hoping to have builds run under 10 minutes instead of the 15-20 I currently see - 75% of the time is spent on the publish task.

[dotnet-policy-service]

Tagging subscribers to 'arch-wasm': @lewing, @pavelsavara
See info in area-owners.md if you want to be subscribed.

[maraf]

I going to close the issue as resolved.
Feel free to continue the discussion or reopen it if there is actionable item on runtime side.