[danleh]

Part of #277. Follow-up to #188. cc @pavelsavara @maraf

Build dotnet-interp-wasm and dotnet-aot-wasm with .NET SDK 11.0.100-rc.3.26522.148 (was 9.0.305). The runtime pack's Emscripten moves from 3.1.56 to 6.0.3.

.NET 11 compiles the runtime and the AOT code with -fwasm-exceptions -sWASM_LEGACY_EXCEPTIONS=0, so the binaries use the standard exception-handling instructions (try_table, throw_ref) directly. build.sh no longer rewrites dotnet.native.wasm with wasm-opt --translate-to-exnref, the workaround from #188.

To review (6 files, +27/−27; build.sh writes the other 52: build.log, dotnet_sdk_info.txt and 50 files in build-interp/ and build-aot/):

• src/global.json selects SDK 11.0.100-rc.3.26522.148, and dotnet.csproj targets net11.0.
• The trimmed library set changed: System.Collections.Concurrent.wasm is gone and System.Security.Cryptography.wasm is new. JetStreamDriver.js (one line) and benchmark.js preload the new set.
• The AOT build's boot config lists every assembly as a core assembly, so benchmark.js marks all AOT assemblies isCore.
• The minifier renamed the function that logs the ArrayBuffer instantiation warning (w → v), so the perl command in build.sh that strips the warning now matches any one-letter name.
• README.md drops stale notes about installing wasm-tools and patching import.meta.url for jsc.

The C# benchmark code does not change.

Binaries: a browser loads 2.6 MB more for the two tests (19.4 MB instead of 16.8 MB); most of it is the AOT dotnet.native.wasm, which grows by 1.56 MB (19%). With the .symbols files and the ICU data files that the tests do not load, the repository grows by 4.2 MB.

Scores (measured on a Linux x64 workstation with jsvu shells, each test alone in a fresh shell, 6 rounds; change of the mean score, rounds won in parentheses, bold = statistically significant at 95% confidence; @kmiller68 may want to check on macOS / arm64):

Test	d8 (15.9.60)	jsc (325217)	SpiderMonkey (160.0b3)
dotnet-interp-wasm	+1.3% (5/6)	+3.7% (4/6)	+2.1% (4/6)
dotnet-aot-wasm	+3.5% (4/6)	−1.7% (3/6)	+0.8% (2/6)
Geomean	+2.4% (5/6)	+0.9% (3/6)	+1.5% (3/6)

Test	d8 First / Average	jsc First / Average	SpiderMonkey First / Average
dotnet-interp-wasm	−2.9% / +3.1%	+4.4% / +3.0%	+0.2% / +3.4%
dotnet-aot-wasm	−2.8% / +6.7%	−9.2% / +1.4%	−7.4% / +5.7%

The AOT dotnet.native.wasm is 19% larger, so the first iteration, which compiles it, takes longer (d8 −2.8%, jsc −9.2%, SpiderMonkey −7.4%), while later iterations improve (+6.7% / +1.4% / +5.7%).

.NET 11 GA is due on November 10, inside this PR's review window. I'll switch global.json to 11.0.100, rebuild and update the numbers before merging.

[netlify]

✅ Deploy Preview for webkit-jetstream-preview ready!

Name	Link
🔨 Latest commit	ff4f556
🔍 Latest deploy log	https://app.netlify.com/projects/webkit-jetstream-preview/deploys/6aea6bfe910fe44ae587cbd2
😎 Deploy Preview	https://deploy-preview-329--webkit-jetstream-preview.netlify.app
📱 Preview on mobile	Toggle QR Code... Use your smartphone camera to open QR code link.
🤖 Make changes	Run an agent on this branch

---

To edit notification comments on pull requests, go to your Netlify project configuration.

[maraf]

Looks good to me!

Just a note, .NET 11 GA is coming soon in case you would prefer a more official version (not that there will be any change in the WebAssembly workload).