BAZEL_VS / BAZEL_VC don't account for custom install locations well.

[laramiel]

Bazel fails to find vc installation.

I'm trying to use bazel with a non-standard ms_buildtools install location, and it fails to find all the tools.
Specifically, I've installed ms_buildtools like this:

--locale en-US --installPath C:\BuildTools --config config.txt

config.txt:
{
"version": "1.0",
"components": [
"Microsoft.VisualStudio.Component.Roslyn.Compiler",
"Microsoft.Component.MSBuild",
"Microsoft.VisualStudio.Component.CoreBuildTools",
"Microsoft.VisualStudio.Workload.MSBuildTools",
"Microsoft.VisualStudio.Component.Windows10SDK",
"Microsoft.VisualStudio.Component.VC.CoreBuildTools",
"Microsoft.VisualStudio.Component.VC.Tools.x86.x64",
"Microsoft.VisualStudio.Component.VC.Redist.14.Latest",
"Microsoft.VisualStudio.Component.Windows10SDK.18362",
"Microsoft.VisualStudio.Component.VC.CMake.Project",
"Microsoft.VisualStudio.Component.TestTools.BuildTools",
"Microsoft.Net.Component.4.8.SDK",
"Microsoft.Net.Component.4.6.1.TargetingPack",
"Microsoft.VisualStudio.Component.VC.CLI.Support",
"Microsoft.VisualStudio.Component.VC.ASAN",
"Microsoft.VisualStudio.Workload.VCTools"
]
}

When running bazel build, it doesn't really matter what I set BAZEL_VC to, bazel fails to find the file VCVARSALL.BAT

in this configuration VCVARSALL.bat lives here:

C:\BuildTools\VC\Auxiliary\Build

while cl.exe, etc live here (among other places)

C:\BuildTools\VC\Tools\MSVC\14.25.28610\bin\Hostx64\x64

The windows_cc_configure.bzl file knows about this, but it looks at the path to determine the version. Since BuildTools does not include the magic string 2019, this fails.

It seems more reasonable to match against the file layout.

[laszlocsomor]

Looks like windows_cc_configure.bzl needs to be fixed.

Short-term, can you try creating a junction C:\BuildTools\2017\VC --> C:\BuildTools\VC and setting BAZEL_VC=C:\BuildTools\2017\VC? Not sure it will work, but worth giving it a try.

[tomlu]

We hit this as well. I solved it by pulling out the generated BUILD file from the local_cc_config, fixing the paths, then checking it in. VCVARSALL.bat isn't really needed then since it's only used during workspace configuration.