"The input line is too long" during build

[kant2002]

When I build CoreRT from command line in x64 dev command line there error after some time

>build.cmd
Doing a clean build

Could Not Find D:\d\kant\GitHub\dotnet\corert\bin\Logs\*_Windows_NT__x64__Debug.*
Checking pre-requisites...

Commencing CoreRT Repo build

Commencing build of native components for Windows_NT.x64.Debug

The input line is too long.
The syntax of the command is incorrect.

My prior experience suggest that this is happens during call of

"C:\Program Files (x86)\Microsoft Visual Studio\2019\Community\\VC\Auxiliary\Build\vcvarsall.bat" x86_amd64

This is happens IIRC due to long PATH variable.

[kant2002]

To troubleshoot issue I set set VSCMD_DEBUG=3 in command prompt to see where error happens.
After being tired to cleanup of the PATH variable, I just skip tests by running build.cmd skiptests. These tests can run separately

[MichalStrehovsky]

We're in the process of moving the repo to runtimelab (https://github.com/dotnet/runtimelab/tree/feature/NativeAOT). The way tests are run will be different there (it will align with how CoreCLR tests are built/run).

(Let's not spend time trying to fix this.)

You can already build things out of that repo/branch - e.g. to get the nuget packages, run build.cmd nativeaot+libraries+installer -c Release. We just don't have Nuget publishing yet, so in waiting more right now.

[kant2002]

Thanks. I just document what issue I do have and how I troubleshoot. That definitely can help somebody even if for only month. Will try with runtimelab repo steps. What is proper way to document building on that repo?

[MichalStrehovsky]

Yep, I just wanted to make sure somebody doesn't pick this issue up and work on fixing it, because it's rearranging deck chairs on the Titanic. We're not bringing over the test/build system.

We don't have docs on how to work in the runtimelab NativeAOT branch yet. It's mostly the same workflow as CoreCLR, with extra arguments passed to scripts here and there.