dotnet / dotnet/aspnetcore

[Known Build Error] Failed webcil conversion: image is too small

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#61,987 7 comments 0 reactions 1 assignee Claimed by @maraf View on GitHub
area-blazor Known Build Error
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Description

## Build Information
Build: https://dev.azure.com/dnceng-public/cbb18261-c48f-4abb-8651-8cdcb5474649/_build/results?buildId=1043546&view=logs&j=d9092465-e29c-5735-3051-a3146222728b
Build error leg or test failing: Build / Test: Windows local development validation / Build (Release)
Pull request: https://github.com/dotnet/aspnetcore/pull/61748

## Error Message

Fill the error message using [step by step known issues guidance](https://github.com/dotnet/arcade/blob/main/Documentation/Projects/Build%20Analysis/KnownIssueJsonStepByStep.md).

```json
{
"ErrorMessage": "",
"ErrorPattern": "error : Failed to convert .*.dll' to webcil: Image is too small.",
"BuildRetry": false,
"ExcludeConsoleLog": false
}
```

```
Wasm.Performance.TestApp (Blazor output) -> D:\a\_work\1\s\src\Components\benchmarkapps\Wasm.Performance\TestApp\bin\Release\net10.0\wwwroot
Optimizing assemblies for size may change the behavior of the app. Be sure to test after publishing. See: https://aka.ms/dotnet-illink
Optimizing assemblies for size. This process might take a while.
C:\Users\cloudtest\.nuget\packages\microsoft.net.sdk.webassembly.pack\10.0.0-preview.5.25260.104\build\Microsoft.NET.Sdk.WebAssembly.Browser.targets(631,5): error : Failed to convert 'D:\a\_work\1\s\artifacts\obj\BasicTestApp\Release\net10.0\linked\System.Private.Xml.dll' to webcil: Image is too small. [D:\a\_work\1\s\src\Components\test\testassets\BasicTestApp\BasicTestApp.csproj]
Publishing without optimizations. Although it's optional for Blazor, we strongly recommend using `wasm-tools` workload! You can install it by running `dotnet workload install wasm-tools` from the command line.
BasicTestApp -> D:\a\_work\1\s\src\Components\test\E2ETest\bin\Release\net10.0\trimmed-or-threading\BasicTestApp\
```

The exception is thrown by PEBinaryReader in
https://github.com/dotnet/runtime/blob/2e77d32dfcd5465434e4b0963e9be50b749521f6/src/libraries/System.Reflection.Metadata/src/System/Reflection/PortableExecutable/PEBinaryReader.cs#L118
called by
https://github.com/dotnet/runtime/blob/2e77d32dfcd5465434e4b0963e9be50b749521f6/src/tasks/Microsoft.NET.Sdk.WebAssembly.Pack.Tasks/ConvertDllsToWebCil.cs#L70

### Known issue validation
**Build: :mag_right:** https://dev.azure.com/dnceng-public/public/_build/results?buildId=1043546
**Error message validated:** `[error : Failed to convert .*.dll' to webcil: Image is too small.`]
**Result validation:** :white_check_mark: Known issue matched with the provided build.
**Validation performed at:** 5/19/2025 7:10:00 AM UTC

### Report
#### Summary
|24-Hour Hit Count|7-Day Hit Count|1-Month Count|
|---|---|---|
|0|0|0|

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