[wasm] Emit producers and build_id custom sections (native, webcil, R2R) - #130768
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Co-authored-by: pavelsavara <271576+pavelsavara@users.noreply.github.com>
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Pull request overview
This PR prototypes emitting WebAssembly tool-conventions custom sections (producers, build_id) and surfacing a buildId value through the browser-wasm JavaScript API, wiring it through the Mono/CoreCLR relink pipelines and stamping WebCIL/R2R wasm outputs.
Changes:
- Add a reusable managed
WasmCustomSectionWriterand an MSBuild task to generate a linkable wasm object contributing.NETentries to theproducerssection during relink. - Plumb
WasmNativeBuildIdthrough build targets/tasks and exposeruntimeBuildInfo.buildIdin the JS public API surface. - Add WBT coverage for relink/webcil metadata sections and a design doc describing the approach.
Reviewed changes
Copilot reviewed 38 out of 42 changed files in this pull request and generated 8 comments.
Show a summary per file
| File | Description |
|---|---|
| src/tasks/WasmAppBuilder/WebcilConverter.cs | Exposes build-id/version passthrough to Webcil converter. |
| src/tasks/WasmAppBuilder/WasmEmitProducersObject.cs | New task writing producers wasm object for linker merge. |
| src/tasks/Microsoft.NET.WebAssembly.Webcil/WebcilWasmWrapper.cs | Appends producers/build_id to wrapped WebCIL wasm. |
| src/tasks/Microsoft.NET.WebAssembly.Webcil/WebcilConverter.cs | Wires metadata options into wrapper output. |
| src/tasks/Microsoft.NET.WebAssembly.Webcil/Microsoft.NET.WebAssembly.Webcil.csproj | Links shared custom-section writer into task assembly. |
| src/tasks/Microsoft.NET.Sdk.WebAssembly.Pack.Tasks/ConvertDllsToWebCil.cs | Passes build-id/product version into WebCIL conversion. |
| src/native/rollup.config.defines.js | Adds buildId rollup constant from env. |
| src/native/libs/System.Native.Browser/native/index.ts | Overrides runtimeBuildInfo.buildId from relinked native module. |
| src/native/libs/System.Native.Browser/libSystem.Native.Browser.footer.js | Exposes WASM_BUILD_ID via $DOTNET during emcc link. |
| src/native/libs/Common/JavaScript/types/public-api.ts | Extends public RuntimeAPI typing with buildId. |
| src/native/libs/Common/JavaScript/types/ems-ambient.ts | Adds buildId to emscripten ambient DOTNET shape. |
| src/native/libs/Common/JavaScript/loader/index.ts | Seeds runtimeBuildInfo.buildId from rollup constant. |
| src/native/libs/Common/JavaScript/loader/dotnet.d.ts | Updates generated public typings for buildId. |
| src/mono/wasm/Wasm.Build.Tests/NativeRebuildTests/WasmMetadataSectionsTests.cs | New tests validating producers/build_id emission. |
| src/mono/wasm/build/WasmApp.Common.targets | Forces native relink when WasmNativeBuildId is set. |
| src/mono/sample/wasm/Directory.Build.targets | Propagates WasmNativeBuildId through nested builds. |
| src/mono/sample/wasm/browser-advanced/Wasm.Advanced.Sample.csproj | Sample configuration updates (currently problematic). |
| src/mono/nuget/Microsoft.NET.Workload.Mono.Toolchain.Current.Manifest/WorkloadManifest.targets.in | Treats WasmNativeBuildId as relink-triggering. |
| src/mono/nuget/Microsoft.NET.Sdk.WebAssembly.Pack/build/Microsoft.NET.Sdk.WebAssembly.Browser.targets | Passes build-id/version into ConvertDllsToWebCIL task. |
| src/mono/browser/runtime/types/internal.ts | Adds buildId to emscriptenBuildOptions typing. |
| src/mono/browser/runtime/types/index.ts | Extends runtime API typing with buildId. |
| src/mono/browser/runtime/rollup.config.js | Adds buildId constant in mono runtime rollup config. |
| src/mono/browser/runtime/loader/globals.ts | Formatting-only changes. |
| src/mono/browser/runtime/loader/assets.ts | Formatting-only changes. |
| src/mono/browser/runtime/globals.ts | Copies buildId from relinked module into runtimeBuildInfo. |
| src/mono/browser/runtime/exports.ts | Seeds runtimeBuildInfo.buildId from rollup constant. |
| src/mono/browser/runtime/es6/dotnet.es6.lib.js | Plumbs WASM_BUILD_ID into emcc-evaluated options blob. |
| src/mono/browser/runtime/dotnet.d.ts | Updates generated public typings for buildId. |
| src/mono/browser/build/BrowserWasmApp.targets | Mono relink: emits producers object + build-id linker/env wiring. |
| src/mono/browser/build/BrowserWasmApp.CoreCLR.targets | CoreCLR relink: emits producers object + build-id linker/env wiring. |
| src/mono/browser/browser.proj | Treats WasmNativeBuildId as runtime-pack defaultable property. |
| src/coreclr/tools/Common/Wasm/WasmCustomSectionWriter.cs | New encoder/merger for producers/build_id custom sections. |
| src/coreclr/tools/Common/Compiler/ObjectWriter/WasmObjectWriter.cs | Stamps producers/build_id into R2R webcil wasm output. |
| src/coreclr/tools/aot/ILCompiler.ReadyToRun/ILCompiler.ReadyToRun.csproj | Links shared custom-section writer into ILC tool. |
| src/coreclr/tools/aot/ILCompiler.ReadyToRun/Compiler/ReadyToRunCodegenCompilationBuilder.cs | Plumbs wasm build-id option through compilation pipeline. |
| src/coreclr/tools/aot/ILCompiler.ReadyToRun/Compiler/ReadyToRunCodegenCompilation.cs | Carries wasm build-id into object emission. |
| src/coreclr/tools/aot/ILCompiler.ReadyToRun/CodeGen/ReadyToRunObjectWriter.cs | Passes wasm build-id through to WasmObjectWriter. |
| src/coreclr/tools/aot/crossgen2/Properties/Resources.resx | Adds help text for new crossgen2 option. |
| src/coreclr/tools/aot/crossgen2/Program.cs | Wires new option into ReadyToRun builder. |
| src/coreclr/tools/aot/crossgen2/Crossgen2RootCommand.cs | Adds --wasm-native-build-id option. |
| src/coreclr/hosts/corerun/wasm/libCorerun.extpost.js | Adds buildId field to corerun runtimeBuildInfo. |
| docs/design/mono/wasm-custom-sections.md | Design doc describing custom section strategy and properties. |
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| if (moduleBytes.Length < 8 || BitConverter.ToUInt32(moduleBytes, 0) != WasmMagic) | ||
| throw new InvalidDataException("Not a WebAssembly module (bad magic)."); |
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| uint version = BitConverter.ToUInt32(moduleBytes, 4); | ||
| if (version != 1) | ||
| throw new InvalidDataException($"Unsupported WebAssembly module version {version}."); |
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| if (mergedProducers is not null) | ||
| WriteProducersSection(ms, mergedProducers); | ||
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| if (buildId is not null) | ||
| WriteBuildIdSection(ms, buildId); | ||
|
|
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| `runAOTCompilation: ${RUN_AOT_COMPILATION}, ` + | ||
| `wasmEnableThreads: ${!!PTHREADS}, ` + | ||
| `gitHash: "${gitHash}", ` + | ||
| `buildId: "${WASM_BUILD_ID}", ` + | ||
| `});`; |
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| catch (Exception ex) | ||
| { | ||
| Log.LogError($"Failed to write producers object '{OutputPath}': {ex.Message}"); | ||
| return false; | ||
| } |
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| <WasmProfilers>browser:callspec=N:Sample</WasmProfilers> | ||
| <WasmNativeBuildId>Advanced-1a2b3c4d5e6f7788-ID</WasmNativeBuildId> | ||
|
|
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| <!-- build_id value exposed on runtimeBuildInfo.buildId; kept in sync with the wasm-ld - -build-id flag. --> | ||
| <EmscriptenEnvVars Include="WASM_BUILD_ID=$(_WasmNormalizedBuildId)" Condition="'$(_WasmNormalizedBuildId)' != ''" /> |
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| var webcilWriter = Microsoft.WebAssembly.Build.Tasks.WebcilConverter.FromPortableExecutable(inputPath: dllFilePath, outputPath: tmpWebcil, logger: logAdapter, webcilVersion: WebcilVersion); | ||
| webcilWriter.ProductVersion = ProductVersion ?? string.Empty; | ||
| webcilWriter.BuildId = ParseBuildId(WasmNativeBuildId); | ||
| webcilWriter.ConvertToWebcil(); |
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Resolve Browser WASM custom-section conflicts with the current WebCIL writer and app-relink infrastructure. Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>
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Emits the two WebAssembly tool-conventions custom sections —
producersandbuild_id— into the WebAssembly artifacts produced by the .NET wasm toolchain, for both Mono and CoreCLR.Where the sections are emitted
producersbuild_iddotnet.native.wasm(app native re-link)wasm-ldwasm-ldbuild-id linker flag, only when$(WasmNativeBuildId)is setConvertDllsToWebcil)WebcilWasmWrapper$(WasmNativeBuildId)if set, otherwise a per-file SHA-256 content hashWebCilObjectWriter--wasm-native-build-idif set, otherwise a content hashAll three paths reuse
WasmCustomSectionWriter, linked into the Webcil task assembly and the ReadyToRun compiler, so there is one implementation of the section encoding.build_iddotnet.native.wasmonly when a value is provided; there is intentionally no implicit random-per-build ID.$(WasmNativeBuildId)accepts a hexadecimal value, pins the ID, and forces a native application re-link.--wasm-native-build-idoption for R2R Webcil output.producersThe generated entries are:
language=C#processed-by=<Mono|CoreCLR|WebCIL>sdk=.NETFor an application native re-link,
WasmEmitProducersObjectcreates a small relocatable object that is passed towasm-ld. Emission can be disabled with$(WasmEmitProducersSection)=false.JavaScript exposure
runtimeBuildInfo.buildIdsurfaces the native module'sbuild_idon both Mono and CoreCLR:dotnet.*.jsbuild: a rollup constant (consts:buildId)WASM_BUILD_IDand overrides the rollup constantMSBuild properties
WasmNativeBuildIdbuild_idfor the native module; Webcil modules fall back to a content hash.WasmEmitProducersSectionproducerssection. Defaults totrue.Tests
src/mono/wasm/Wasm.Build.Tests/NativeRebuildTests/WasmMetadataSectionsTests.cscovers the sections indotnet.native.wasmand Webcil modules, with and without an explicitly pinned ID.Local validation after merging current
main:.\build.cmd -bl -os browser -subset clr+libs+host -c Debug /p:RuntimeFlavor=CoreCLR.\dotnet.cmd build -bl:artifacts\log\pr130768-sample.binlog /p:TargetOS=browser /p:TargetArchitecture=wasm /p:Configuration=Debug /p:RuntimeFlavor=CoreCLR /p:WasmBuildNative=true /p:WasmNativeBuildId=1a2b3c4d5e6f7788 src\mono\sample\wasm\browser\Wasm.Browser.Sample.csprojdotnet.native.wasmcontainsbuild_idbytes1a2b3c4d5e6f7788.\dotnet.cmd build -bl:artifacts\log\pr130768-wbt.binlog /p:TargetOS=browser /p:TargetArchitecture=wasm /p:Configuration=Debug /p:RuntimeFlavor=CoreCLR /t:Test src\mono\wasm\Wasm.Build.Tests /p:TestUsingWorkloads=false /p:InstallWorkloadForTesting=false /p:XUnitClassName=Wasm.Build.NativeRebuild.Tests.WasmMetadataSectionsTestsNETSDK1147, requiring thewasm-toolsworkload before reaching the test targetsKnown limitation from local validation:
dotnet-producers.ois generated and included in the Emscripten response file, but the final relinked CoreCLRdotnet.native.wasmdid not contain aproducerssection. This still needs investigation before theproducerspath is considered validated.Not included / deferred
dotnet.native.wasmused by non-relinking applications.Design notes:
docs/design/mono/wasm-custom-sections.md.Merged current
mainatced3e57460dd57581734dfd4d7888cb3e2eca028in merge commitc157dd70460071dbb01eb27bda091b0f6262c605.Resolves #96334
Resolves #91049
Note
This PR description was updated with the assistance of GitHub Copilot.