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ilverify-failure

Testing & Quality
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Fix ILVerify baseline failures when IL shape changes (codegen, new types, method signatures). Use when CI fails on ILVerify job.

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Source SKILL.md: https://github.com/dotnet/dotnet/blob/HEAD/src/fsharp/.github/skills/ilverify-failure/SKILL.md

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ILVerify Baseline

When to Use

IL shape changed (codegen, new types, method signatures) and ILVerify CI job fails.

Offset-Only Differences

Changes that only shift IL byte offsets ([offset 0x...]) — for example adding code above an existing error site — are detected automatically and do not fail CI. A warning is printed suggesting a baseline update. No action is required, but refreshing baselines keeps them accurate.

Update Baselines

TEST_UPDATE_BSL=1 pwsh tests/ILVerify/ilverify.ps1

Or use the /run ilverify PR comment command to update baselines via CI.

Baselines Location

tests/ILVerify/*.bsl

Verify

Re-run without TEST_UPDATE_BSL=1, should pass.