Who contributed to .NET on June 15, 2026?

4 developers shipped this update, including AndyAyersMS, max-charlamb, pavelsavara, and AlekseyTs.

What were the notable .NET updates?

JIT: don't claim rotates set ZF on xarch, [cdac] Pipeline refactor + StackWalk doc cleanup + DataGenerator build fix, and [browser][wasm] Prep changes ahead of emsdk bump.

@dotnet

The .NET runtime, ASP.NET, and the C# tooling

github ↗

Pick a date

Topics: .NET Full archive →

The Wire · Showcase

JIT FLAGS BUG FIXES CRITICAL PATH FOR X86 ROTATE OPERATIONS

By RepoJournal · Filed 06:04 UTC on June 15, 2026 · About .NET

4 people shipped this

AndyAyersMS @AndyAyersMS 1 cited

max-charlamb @max-charlamb 1 cited

pavelsavara @pavelsavara 1 cited

AlekseyTs @AlekseyTs 1 cited

The runtime shipped a precision fix that stops the JIT from incorrectly claiming rotate instructions set the zero flag, a bug that could silently corrupt conditional logic downstream.

The core issue landed in dotnet/runtime: ROL and ROR instructions on x86 only affect the carry flag (CF), not zero flag (ZF), but the JIT was claiming otherwise [1]. This matters because downstream code relies on those flag states to make branching decisions. If the JIT lies about which flags are set, you get silent logic corruption that's nearly impossible to debug in production. In parallel, the diagnostics team consolidated follow-ups to the cDAC refactor, cleaning up StackWalk documentation and fixing the DataGenerator build [2]. On the WASM front, the team split out browser compatibility work ahead of the Emscripten 5.0.6 bump, bumping Firefox support from 125.0.1 to 140.11.0esr and prepping the toolchain transition [3]. Roslyn fixed a records codegen bug where synthesized methods were making non-virtual calls to abstract methods, which violated the inheritance contract [4].

Action items

→ Review JIT flag fix [ref:1] before next runtime build - verify your rotate-dependent code paths dotnet/runtime [plan]
→ Track the Emscripten 5.0.6 bump; these WASM prep changes [ref:4] can ship independently dotnet/runtime [monitor]
→ Test records with abstract method inheritance if you use C# 9+ record types dotnet/roslyn [plan]

References

[1] JIT: don't claim rotates set ZF on xarch ↗ dotnet/runtime
[2] [cdac] Pipeline refactor + StackWalk doc cleanup + DataGenerator build fix ↗ dotnet/runtime
[3] [browser][wasm] Prep changes ahead of emsdk bump ↗ dotnet/runtime
[4] Records: Avoid synthesized non-virtual calls to abstract methods ↗ dotnet/roslyn

Quick answers

What shipped in .NET on June 15, 2026?: The runtime shipped a precision fix that stops the JIT from incorrectly claiming rotate instructions set the zero flag, a bug that could silently corrupt conditional logic downstream. In total, 6 commits and 6 pull requests landed.
Who contributed to .NET on June 15, 2026?: 4 developers shipped this update, including AndyAyersMS, max-charlamb, pavelsavara, and AlekseyTs.
What were the notable .NET updates?: JIT: don't claim rotates set ZF on xarch, [cdac] Pipeline refactor + StackWalk doc cleanup + DataGenerator build fix, and [browser][wasm] Prep changes ahead of emsdk bump.

WASM RUNTIME SHRINKS 3.6% AS DOTNET HARDENS DEBUGGER EXPORTS

The JIT compiler just cut 815 kilobytes from WebAssembly Core Library by folding address constants into load instructions, while the runtime fixed a silent failure in WASI debugging that would strip metadata from stripped binaries.

dotnet 13 shipped 1-min read

@dotnet 3 days ago

RUNTIME FIXES KERBEROS FALLBACK ON UNIX, APPHOST CONVERTS TO C

The managed SPNEGO implementation now falls back to NTLM when Kerberos credentials go missing on Linux, closing a critical auth gap that broke enterprise deployments [ref:1].

dotnet 120 shipped 1-min read

@dotnet 4 days ago

MACIOS DOCS OVERHAUL SPANS 31 TYPES, ASPNETCORE VALIDATION MOVES TO SOURCE GENERATION

Rolf Bjarne shipped 31 types with proper XML documentation across macios while aspnetcore refactors validation classes out of the public API entirely.

dotnet 25 shipped 1-min read

@dotnet 5 days ago

SQLCLIENT KILLS PLATFORM-SPECIFIC BUILDS, ASPNETCORE HARDENS SIGNALR

SqlClient unified its Windows and Unix code paths without restructuring the NuGet package, collapsing build complexity across the entire SNI layer.

dotnet 97 shipped 2-min read

Elsewhere on the wire

AI Agents about 21 hours ago

CLINE SHIPS FIVE CRITICAL AGENT FIXES AFTER END-TO-END TESTING BLITZ

Saoudrizwan just landed a cascade of fixes that prevent the agent loop from running wild, stop file reads from resolving to the wrong directory, and plug the compaction pipeline.

ai-agents 16 shipped 2-min read

Local LLMs about 21 hours ago

LLAMA.CPP SHIPS MINIMAX-M3 SPARSE ATTENTION, VLLM UNLOCKS HETEROGENEOUS PREFILL-DECODE

The inference stack gets a new model architecture and a fundamental shift in how prefill and decode can run on different hardware configurations.

+10

llms 125 shipped 1-min read

@CachyOS about 21 hours ago

GLIBC 2.43 REBUILD SHIPS, INSTALLER JUMPS TO C++26

CachyOS pushed glibc 2.43 through the pipeline while the CLI installer upgraded its C++ standard to C++26, signaling a major refresh across core infrastructure.

infra 97 shipped 1-min read

Elixir & Phoenix about 21 hours ago

ECTO FIXES SUBQUERY PLANNING IN JOINS, ELIXIR PATCHES IEX PARSING

Ecto's query planner now handles subqueries correctly in interpolated join filters, while Elixir fixes a syntax error that broke 'not in' as a continuation operator in IEx.