Timing build break in multi-targeting tool project due to DotnetToolSettings.xml

[AArnott]

Describe the bug

A multi-targeting tool project constructs the DotnetToolSettings.xml file at the same location from all target frameworks:

From Microsoft.NET.PackTool.targets:

<_ToolsSettingsFilePath>$(BaseIntermediateOutputPath)DotnetToolSettings.xml</_ToolsSettingsFilePath>

This leads to a race condition in the build where each target framework wants to write this file to the same location, leading to timing breaks.

In the binlog viewer below, notice how net8.0 and net9.0 both write to the file at the same path:

Here's the full binlog
build.zip

And a github workflow that failed at least twice in a row due to this timing break:
https://github.com/AArnott/DotNetRepoTools/actions/runs/15973577065/job/45052231169?pr=96

To Reproduce

I suspect any csproj with properties like these is vulnerable to it:

  <PropertyGroup>
    <!-- Multi-target so that the tool will run on the latest runtime on the user's machine.
         This is important so that if the user only has an SDK installed that matches the latest runtime version,
         we'll be able to find MSBuild via that SDK.  -->
    <TargetFrameworks>net8.0;net9.0</TargetFrameworks>
    <OutputType>exe</OutputType>
    <ToolCommandName>repo</ToolCommandName>
    <PackAsTool>True</PackAsTool>
    <Description>A CLI tool with commands to help maintain .NET codebases.</Description>
  </PropertyGroup>

full project.

[baronfel]

We fixed this in 10 in #47788, and backported it to 9.0.100, so it should have flowed into all 9 releases by now - are you on latest?

[AArnott]

Yes, I'm on 9.0.301

[baronfel]

You're right - for some reason that didn't flow to 9.0.2xx and 9.0.3xx. It should have flowed to at least 9.0.3xx (2xx is out of support now). We'll get that done ASAP. EDIT: It has flowed

But it's just not in the 301 SDK. It appears there was a timing issue. I've checked the 302 SDK payloads that'll release in a couple weeks and those do contain the fix. So I'll close this pending release.