[wasm][R2R] Runtime_70259 asserts in ToPortableEntryPoint

[lewing]

Description

JIT/Regression/JitBlue/Runtime_70259 passes in the CoreCLR browser-wasm interpreter lane, but asserts when the test assembly is compiled with Crossgen2 and run as ReadyToRun. The test creates an open delegate for an interface method and invokes it through a tail call.

The interpreter-only version of this assertion was tracked by #124221 and fixed by #125138. The ReadyToRun test-assembly path remains broken.

Reproduction Steps

1. Build the CoreCLR browser-wasm runtime test layout.
2. Build JIT/Regression/Regression_2.
3. Run its generated script with RunCrossGen2=1 and CompositeBuildMode=1 so Runtime_70259.dll is compiled to wasm ReadyToRun.

The relevant test is src/tests/JIT/Regression/JitBlue/Runtime_70259/Runtime_70259.il.

Expected behavior

Runtime_70259 passes and returns 100, matching the interpreter lane.

Actual behavior

The ReadyToRun run aborts with:

ASSERT FAILED
    Expression: portableEntryPoint->IsValid()
    Location:   src/coreclr/vm/precode_portable.cpp:109
    Function:   ToPortableEntryPoint
Frame (InterpreterFrame):
   0) System.Func`2[__Canon,Int32]::IL_STUB_DelegateShuffleThunk, IR_0014
Expected: 100
Actual: 1

Regression?

No known regression. This was exposed by adding test-assembly ReadyToRun coverage to the merged CoreCLR browser-wasm runtime-test runner.

Known Workarounds

Skip this test when both wasm and ReadyToRun test-assembly execution are active. The interpreter lane remains enabled.

Configuration

• CoreCLR browser-wasm, Checked
• wasm32
• Test assembly compiled by Crossgen2 with ReadyToRun enabled

Other information

Related issues include #124221 (the now-fixed interpreter case) and #130840 (a different wasm ReadyToRun failure involving open-instance virtual/interface delegates).

Note

This issue was authored with the assistance of GitHub Copilot.

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[MihuBot]

I'm a bot. Here is a possible related and/or duplicate issue (I may be wrong):

• Wasm: Runtime_79354 fails with test assembly R2R #131886

[lewing]

Duplicate of #131886, which was filed on 2026-08-05 — a month before this one. My search when filing did not turn it up; thanks to @lewing for spotting it.

Same defect, identical signature down to the IR offset:

	#131886	this issue
Assert	portableEntryPoint->IsValid()	same
Location	precode_portable.cpp:109, ToPortableEntryPoint	same
Frame	MyDelegate::IL_STUB_DelegateShuffleThunk, IR_0014	System.Func\2[__Canon,Int32]::IL_STUB_DelegateShuffleThunk, IR_0014`
Trigger	open delegate over an interface method, invoked from R2R code	same, reached via a tail call
Passes	interpreted	interpreted
Fails	test assembly R2R on wasm	test assembly R2R on wasm

Only the test differs — Runtime_79354 there, Runtime_70259 here. #131886 also already has a root-cause analysis (INTOP_CALLI treating CID_VirtualOpenDelegateDispatch as a portable entry point) and a working prototype fix, so it is the better issue to keep. See also #130840, which looks like the same family.

I have added the Runtime_70259 details to #131886 so nothing is lost.

One loose end: Runtime_70259 is disabled on this path in main by an ActiveIssue pointing at this now-closed issue, in both Runtime_70259.cs and Runtime_70259.il. That reference should be retargeted to #131886.

Closing in favour of #131886.

Note

This comment was authored with GitHub Copilot.