Build from source on Windows - vcbuild does not prevent failed build attempt without Rust toolchain #66848

Follows on from #63451

Version

v27.0.0-pre cd192cd

Platform

Microsoft Windows NT 10.0.26200.0 x64

Subsystem

build

What steps will reproduce the bug?

On Windows 11 26H2, follow prerequisite Manual install instructions using:

• Python 3.15.0
• Visual Basic 2026 Build Tools 18.11.0 (October 2026)
  • C++ Clang Compiler for Windows (Microsoft.VisualStudio.Component.VC.Llvm.Clang) (22.1.3)
  • MSBuild support for LLVM (clang-cl) toolset (Microsoft.VisualStudio.Component.VC.Llvm.ClangToolset)
• NASM 3.02
• Do not install a Rust toolchain (and otherwise ensure that there is no rustc or cargo installed).

In PowerShell 7 terminal, execute:

git clone https://github.com/nodejs/node
cd node
git switch main
git clean -xfd # if repeating
.\vcbuild.bat
Release\node -e "console.log('Hello from Node.js', process.version)"

How often does it reproduce? Is there a required condition?

No Rust toolchain installed.

What is the expected behavior? Why is that the expected behavior?

If a Rust toolchain is not installed, vcbuild.bat should detect this and then fail fast instead of continuing with the build attempt which is ultimately unsuccessful.

What do you see instead?

Build emits error message and continues:

C:\Program Files (x86)\Microsoft Visual Studio\18\BuildTools\MSBuild\Microsoft\VC\v180\Microsoft.CppCommon.targets(254,5): error MSB8066: Custom build for 'Cargo.toml' exited with code 1
. [C:\Users\mikem\github\NODEJS\node\deps\crates\node_crates.vcxproj]

Directory Release is not created. (out\Release also contains no node.exe)

cc: @StefanStojanovic