Asserts from ILLink analyzers

[stephentoub]

I'm hitting a bunch of asserts while trying to run code analysis over libraries in VS, e.g.

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Issue Details

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I'm hitting a bunch of asserts while trying to run analyzers over libraries in VS, e.g.

Author:	stephentoub
Assignees:	-
Labels:	area-Meta, untriaged
Milestone:	-

Tagging subscribers to this area: @agocke, @sbomer, @vitek-karas
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Issue Details

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I'm hitting a bunch of asserts while trying to run analyzers over libraries in VS, e.g.

Author:	stephentoub
Assignees:	-
Labels:	untriaged, area-Tools-ILLink
Milestone:	-

[sbomer]

@stephentoub can you provide repro instructions? I tried the following but didn't hit an assert:

• Opened System.Data.Common.sln in VS (I have 17.8.0 Preview 2.0)
• Right click on System.Data.Common in the solution -> Analyze and Code Cleanup -> Run Code Analysis On Solution

I'll update my VS to the latest preview and try again.

[sbomer]

The assert looks like it's hitting on delegate creation over a method:

runtime/src/libraries/System.Data.Common/src/System/Data/DataViewListener.cs

Line 104 in e4fbdb9

var handlerCollection = new CollectionChangeEventHandler(ColumnCollectionChanged);

We have support for this with test coverage in the analyzer, and I can run the analysis over a testcase like this code locally without any failure. Maybe it has something to do with the Roslyn version in use, since I think NoneOperation is what Roslyn uses to represent new language features that aren't exposed as proper IOperation types in the analysis APIs. But I'm not sure why delegate creation would be giving NoneOperation.

[vitek-karas]

I also wasn't able to get a repro (even though I followed the steps Stephen sent me). That said, I was wondering if we handle error states. Basically what happens if the operation tree contains errors - that would also probably trigger the assert, which feels wrong. We should somehow filter out the operations which are "known, but not interesting".

[stephentoub]

can you provide repro instructions

I have VS Version 17.9.0 Preview 1.0 [34231.268.main]. I ran the GenerateLibrariesSln.ps1 in the src\libraries directory to create an .sln (it won't build, but it's good enough to then run analyzers over everything). I opened the solution, and then selected Analyze | Run Code Analysis | On Solution. It eventually asserted.

[sbomer]

Pretty sure #94888 will fix this - it should skip NoneOperation in VisitDelegateCreation.