Rainer Sigwald

This feels "by design" to me. I wish we errored when the condition was detected, but I don't know if anyone has used this construct (and thus would be broken...

> Sdk.targets: > > ``` > > > > ``` This doesn't throw an error? 😬 Don't do this: use an Sdk only in your entry-point project.

That feels like a change that's not worth the risk to me: * possiblity of torn imports that you point out (condition changes between props and targets) * paying attention...

I'm going to move this to the MSBuild repo. I don't know offhand why we'd _start_ going down this long-existant codepath now.

> isn't ngen deprecated? ngen is the best JIT-reduction/AOT technology available on .NET Framework 4.8, which is relevant to MSBuild because it's what Visual Studio, one of our major partners,...

> if you have a misauthored task that returns true but logs an error, and you're using a debug build of MSBuild, it will assert I think that's likely common...

It looks like you reverted the BuildAbortedException error-code-scraping stuff. I prefer the revert there but I was asking you to change the BuildSubmission stuff back, since you said you didn't...

I think this is happening for reasons related to #3295: the warning path for evaluation-related warnings is distinct from normal execution-time warnings. In this case, the final value of `MSBuildWarningsAsMessages`...

Smallest repro I could think of: [repro.zip](https://github.com/Microsoft/msbuild/files/2722067/repro.zip)

@botrif I'm not sure I understand the whole situation, but can you expand the Sdk imports into their explicit form, like: ```xml net46 ``` ?