No release since 2.4.5-pre.3 (Oct 12): pack fails package validation (93 errors, CP0016/CP0014/CP0001) after the Polyfill 11.4.5 bump #118

What's wrong

Every CI run on main since the Polyfill 11.4.5 bump (#107, Oct 14) fails in ci / .NET / Analyze & Release at dotnet pack. Package validation (Microsoft.NET.ApiCompat.ValidatePackage.targets(39,5)) reports 93 errors. The latest scheduled run is 41251274153, on dfe79a3.

• Baseline diffs between lib/net7.0 and lib/net8.0: 45 errors, mostly CP0016 on DeepClone's own types, for example T:ktsu.DeepClone.IDeepCloneable:[T:System.Runtime.CompilerServices.NullableContextAttribute] and T:ktsu.DeepClone.DeepCloneable1<0>:[…NullableAttribute]`
• Baseline diffs between lib/netstandard2.1 and lib/net5.0: 3 errors
• Polyfill-type diffs: CP0014 and CP0015 on System.Diagnostics.CodeAnalysis.ExperimentalAttribute (UrlFormat get/set) and on System.Runtime.CompilerServices.DefaultInterpolatedStringHandler, plus 6 × CP0001
• 3 × "Unnecessary suppressions found": DeepClone/CompatibilitySuppressions.xml no longer matches what Polyfill 11.4.5 emits

The last published release is v2.4.5-pre.3 (2026-10-12). VERSION.md on main reads 2.4.5-pre.4, which never shipped.

Why it matters

Nothing merged since Oct 12 can publish. The next fix to any of the open DeepClone bugs (#89, #90, #96, and the rest) will merge and then silently never reach NuGet.

This is the same failure already tracked in other repos (Containers #123, RunCommand #126, ImGuiProvider #83, CaseConverter #149, SvnToGit #151, Sorting #72, FuzzySearch #128, AppDataStorage #358). DeepClone has no issue for it yet.

Suggested fix

Regenerate the suppression file against the current SDK and Polyfill:

dotnet pack DeepClone/DeepClone.csproj -c Release /p:ApiCompatGenerateSuppressionFile=true

Then commit the updated DeepClone/CompatibilitySuppressions.xml. Before committing, check that the new CP0016 and CP0001 entries on ktsu.DeepClone.* types are only nullable-metadata differences between TFMs and not real API removals. If one is a real removal, fix the API rather than suppress it.

Acceptance criteria

• dotnet pack -c Release on main succeeds with no ApiCompat errors
• The next CI run on main publishes a new version to NuGet and creates the GitHub release