17.12.3 breaks build with F# issues

[vsfeedback]

This issue has been moved from a ticket on Developer Community.

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[severity:I'm unable to use this version] [regression] [worked-in:17.10.9]
Scenario:
F# project (.Net 6 - project A) references F# project (.Net Standard 2.0 - Project B)
Build fails for project A finding namespaces referenced in project B.
The referenced project (project B) builds without error.

The same source code builds fine with 17.10.6 (and 17.10.9)

Last successful Azure build was 14 November (see Log_24632_SUCCESS.zip).
Same source code (same commit on Master branch) fails from 27 November (see Log_24757_FAILED.zip)

I was able to reproduce the same build issues when I upgraded my local instance of VS2022 from 17.10.6 to 17.12.3

I'm restoring my old version so I can continue to build without issues, but my pipeline is Azure hosted and fails.

I have logged a DevOps / Azure ticket - TrackingID#2412040030001596

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Original Comments

Feedback Bot on 12/5/2024, 05:32 AM:

We have directed your feedback to the appropriate engineering team for further evaluation. The team will review the feedback and notify you about the next steps.

[0101]

Can you provide a minimal repro for this?

[vzarytovskii]

Can you provide a minimal repro for this?

That is a feedback issue, please refer to internal ticket, it has logs provided.

[0101]

From the logs we can see that fscAnyCpu.exe from VS 17.12.3 produces a (netstandard2.0) DLL that dotnet\sdk/6.0.405/FSharp/fsc.dll seems to have issues consuming (The namespace or module '...' is not defined.)

It's hard to say what the problem is without the source code or at least the DLL that was produced.

[0101]

Another question is why the 6.0.405 compiler is used. Since it's now officially out of support we recommend using a newer version by removing the pinned version from global.json or choosing a newer one.

It's also not quite clear why the ADO VS Build step uses VS built-in compiler for some targets and the SDK one for others.