+function Set-NativeNinjaFirst {
+ # Make the native ninja.exe the one that wins, including inside a Visual
+ # Studio Developer Command Prompt.
+ #
+ # WHY THIS IS INSURANCE RATHER THAN THE FIX. VS ships an x64 ninja.exe even on
+ # ARM64 and puts it on the PATH from
+ # Common7\Tools\vsdevcmd\ext\cmake.bat, which does:
+ # set "PATH=%PATH%;...\CMake\bin;...\CMake\Ninja"
+ # That APPENDS - the VS directories land at the very end of the composed
+ # PATH, behind every machine and user entry. So a native ninja installed
+ # anywhere on the user PATH already beats it, and measurement on an ARM64 box
+ # confirms it does. (An earlier revision of this script claimed VsDevCmd
+ # prepends and that the VS copy therefore always won; that was wrong.)
+ #
+ # It is still worth pinning the order explicitly: winget appends its package
+ # directory to the user PATH, so the margin depends on nothing more than two
+ # append orders staying as they are, in a file Microsoft owns and revises.
+ # Putting the directory first costs nothing and removes the dependency.
+ #
+ # Ninja is worth this attention where a one-off tool would not be: it is
+ # re-invoked for every edge in the build graph, so it is the one place an
+ # emulated binary is paid over and over rather than once.
+ Write-Step 'Native ninja ahead of the Visual Studio copy'
+
+ $candidates = @()
+ $candidates += Get-ChildItem (Join-Path $env:LOCALAPPDATA 'Microsoft\WinGet\Packages') `
+ -Filter 'ninja.exe' -Recurse -Depth 2 -ErrorAction SilentlyContinue |
+ ForEach-Object { $_.FullName }
+ $candidates += @(
+ (Join-Path $env:ProgramFiles 'Ninja\ninja.exe')
+ (Join-Path $env:LOCALAPPDATA 'Programs\Ninja\ninja.exe')
+ )
+ # A ninja already on the PATH counts too - but only if it is not the VS one,
+ # which is the binary this step exists to get out in front of.
+ $onPath = (Get-Command ninja.exe -ErrorAction SilentlyContinue | Select-Object -First 1).Source
+ if ($onPath -and $onPath -notmatch 'CommonExtensions\\Microsoft\\CMake') { $candidates += $onPath }
+
+ $native = $null
+ foreach ($c in ($candidates | Where-Object { $_ -and (Test-Path $_) } | Select-Object -Unique)) {
+ $m = Get-PEMachine $c
+ if ($m -eq $(if ($IsArm64) { 'ARM64' } else { 'x64' })) { $native = $c; break }
+ }
+
+ if (-not $native) {
+ Write-Warning 'No native ninja.exe found. Install it with: winget install Ninja-build.Ninja'
+ Write-Warning 'Until then a build using the Ninja generator gets the x64 ninja Visual Studio bundles.'
+ return
+ }
+
+ Write-Host " native ninja: $native ($(Get-PEMachine $native))"
+ Add-ToUserPath (Split-Path $native -Parent) -Prepend
+}
+
+function Add-LlvmToUserPath {
+ # Put the upstream LLVM's bin directory on the user PATH.
+ #
+ # Two reasons this needs a step rather than trusting the installer:
+ #
+ # 1. WHERE IT LANDS. LLVM's NSIS installer targets %ProgramFiles%\LLVM, and
+ # when it cannot write there - a standard user, no elevation - it does not
+ # fail. It silently falls back to a per-user directory, observed as
+ # %USERPROFILE%\Documents\LLVM, and winget still reports "Successfully
+ # installed". So the package is registered, the compiler is genuinely
+ # there and native, and nothing can find it.
+ # 2. PATH. The installer's "add to PATH" option is not taken in a silent
+ # install, so clang-cl is not a command afterwards either way.
+ #
+ # Appended, not prepended: this is a second compiler kept deliberately
+ # alongside MSVC, and it should not quietly win a `clang-cl` that some script
+ # meant for Visual Studio's copy. Note VS does NOT put its own
+ # VC\Tools\Llvm on the PATH (its clang-cl is reached through CMake's
+ # -T ClangCL), so there is no collision to lose here.
+ Write-Step 'Upstream LLVM on the user PATH'
+ $candidates = @(
+ (Join-Path $env:ProgramFiles 'LLVM\bin')
+ (Join-Path ${env:ProgramFiles(x86)} 'LLVM\bin')
+ (Join-Path $env:LOCALAPPDATA 'Programs\LLVM\bin')
+ (Join-Path ([Environment]::GetFolderPath('MyDocuments')) 'LLVM\bin')
+ (Join-Path $env:USERPROFILE 'Documents\LLVM\bin')
+ )
+ $dir = $candidates | Where-Object { Test-Path (Join-Path $_ 'clang-cl.exe') } | Select-Object -First 1
+ if (-not $dir) {
+ Write-Host ' Not installed (winget install LLVM.LLVM); Visual Studio''s own clang-cl is unaffected.' -ForegroundColor DarkGray
+ return
+ }
+ $exe = Join-Path $dir 'clang-cl.exe'
+ $mach = Get-PEMachine $exe
+ Write-Host " $exe ($mach)"
+ if ($IsArm64 -and $mach -ne 'ARM64') {
+ Write-Warning "This LLVM is $mach, not ARM64. winget install LLVM.LLVM should resolve to the -woa64 build on this host."
+ }
+ if ($dir -notmatch [regex]::Escape($env:ProgramFiles)) {
+ Write-Host ' Note: not under Program Files - the installer fell back to a per-user' -ForegroundColor Yellow
+ Write-Host ' location because it could not write there. Re-run elevated for a machine-wide install.' -ForegroundColor Yellow
+ }
+ Add-ToUserPath $dir
+}
+
+function Get-PEMachine {
+ # Architecture of a PE, read straight from the COFF header: the 2 bytes at
+ # the e_lfanew offset + 4. Cheap, and it answers the only question that
+ # matters here - would this exe run natively, or through emulation?
+ #
+ # Deliberately NOT Get-Command's .FileVersionInfo or the package metadata:
+ # a multi-architecture package (Sysinternals) ships every build in one zip
+ # under different names, and an installer's own metadata says nothing about
+ # which binary got laid down. The file itself cannot be wrong.
+ param([string]$Path)
+ if (-not (Test-Path $Path)) { return $null }
+ try {
+ $fs = [IO.File]::OpenRead($Path)
+ $br = New-Object IO.BinaryReader($fs)
+ try {
+ $fs.Seek(0x3c, 'Begin') | Out-Null
+ $pe = $br.ReadInt32()
+ if ($pe -le 0 -or $pe -gt ($fs.Length - 6)) { return 'not-PE' }
+ $fs.Seek($pe + 4, 'Begin') | Out-Null
+ switch ($br.ReadUInt16()) {
+ 0x8664 { 'x64' }
+ 0xAA64 { 'ARM64' }
+ 0x014c { 'x86' }
+ 0x01c4 { 'ARM32' }
+ default { 'unknown' }
+ }
+ } finally { $br.Close(); $fs.Close() }
+ } catch { $null }
+}
+
+function Invoke-ArchAudit {
+ # Report the actual architecture of the tools this box provisions, resolved
+ # the way a shell would (PATH first, then the usual install roots), so what
+ # is printed is what you would really run.
+ #
+ # This exists because "winget installed it" does not mean "you got the native
+ # build", and the gap is not always where you would guess - Visual Studio's
+ # own bundled ninja.exe is x64 even on an ARM64 host. A per-run audit turns
+ # that from something you trip over into something the log tells you.
+ #
+ # Purely informational: it never fails the run. On x64 everything is expected
+ # to be x64 and the output is dull; the value is on ARM64, where each line is
+ # either native or a known, listed exception.
+ Write-Step "Architecture audit (host: $HostArch)"
+
+ # Resolve against the PATH a NEW shell would get, not this process's.
+ #
+ # The steps above write the HKCU PATH, which a running process never sees -
+ # so auditing $env:PATH would report the state from before this script ran and
+ # warn about a problem it had just fixed. Compose machine + user from the
+ # registry (the order Windows itself uses), then append anything extra this
+ # process happens to carry: that tail is where a Developer Command Prompt's VS
+ # directories live, and keeping it last mirrors how VsDevCmd appends them.
+ $composed = @()
+ foreach ($scope in 'Machine', 'User') {
+ $v = [Environment]::GetEnvironmentVariable('Path', $scope)
+ if ($v) { $composed += ($v -split ';' | Where-Object { $_.Trim() }) }
+ }
+ $composed += ($env:PATH -split ';' | Where-Object { $_.Trim() })
+ $seen = New-Object 'System.Collections.Generic.HashSet[string]' ([StringComparer]::OrdinalIgnoreCase)
+ $searchPath = @($composed | Where-Object { $seen.Add($_.Trim().TrimEnd('\')) })
+
+ function Resolve-OnPath([string]$Exe) {
+ foreach ($d in $searchPath) {
+ $p = Join-Path $d $Exe
+ if (Test-Path $p -PathType Leaf) { return $p }
+ }
+ return $null
+ }
+
+ # Tools with no native ARM64 build available anywhere, with the reason. These
+ # print as expected rather than as problems - see the README's ARM64 section.
+ #
+ # Shorter than it was: BinSkim, OpenCppCoverage and NASM used to be listed
+ # here as accepted emulation, and are now simply not installed on ARM64. That
+ # is the whole shape of the change - the exceptions that were tolerable one at
+ # a time added up to a VM full of x64 binaries.
+ #
+ # rsync came off this list when the release started publishing an arm64
+ # asset. An x64 rsync.exe on an ARM64 box is now a leftover from a run before
+ # that, not an accepted exception, so it warns and gets a remedy below.
+ $KnownEmulated = @{
+ 'iperf3.exe' = 'no ARM64 build published; network-bound anyway'
+ 'py.exe' = 'python.org ships the launcher shim as x86; it execs the native python.exe'
+ 'vswhere.exe' = 'Microsoft ships x86 only; runs once per script'
+ }
+
+ # Fixable cases: a native build DOES exist, something just resolved ahead of
+ # it. Printed with the finding so the log carries the remedy, not just the
+ # complaint.
+ #
+ # ninja is the one that actually bites: Visual Studio bundles an x64 ninja.exe
+ # even on ARM64, and it is re-invoked for every edge in the build graph, so
+ # an emulated one is paid over and over rather than once. The NinjaPath step
+ # puts the native copy first; this is the check that it worked.
+ #
+ # Only two left, and both are for tools ARM64 still installs. The clang-cl and
+ # WinMerge remedies were removed with their rows: advising an install that the
+ # x64-only set has just declined to do would be the audit arguing with the
+ # provisioning.
+ $Remedies = @{
+ 'ninja.exe' = 'Visual Studio bundles an x64 ninja. Install the native one (winget install Ninja-build.Ninja) and re-run - the NinjaPath step puts its directory at the front of the user PATH.'
+ 'cmake.exe' = 'Install the native build with: winget install Kitware.CMake (its MSI is machine-scope, so it needs an administrator).'
+ 'rsync.exe' = 'Left over from before the release published an arm64 asset. Re-run setup-windows-with-uac.ps1 as an administrator to replace it, and the ARM64 ssh.exe beside it, with the native build.'
+ }
+
+ $vs = $null
+ $vsWhereExe = Join-Path ${env:ProgramFiles(x86)} 'Microsoft Visual Studio\Installer\vswhere.exe'
+ if (Test-Path $vsWhereExe) {
+ $vs = & $vsWhereExe -products '*' -property installationPath -format value | Select-Object -First 1
+ }
+
+ # name -> extra candidate paths searched when the name is not on the PATH.
+ $targets = [ordered]@{
+ 'git.exe' = @("$env:LOCALAPPDATA\Programs\Git\cmd\git.exe", (Join-Path $env:ProgramFiles 'Git\cmd\git.exe'))
+ 'python.exe' = @()
+ # Both homes of the launcher: C:\Windows for an all-users install, the
+ # per-user Launcher directory otherwise. Often neither - it is a separate
+ # component from the interpreter, and "- not installed" here next to a
+ # native python.exe is the normal result of an unelevated Python install.
+ 'py.exe' = @("$env:WINDIR\py.exe", "$env:LOCALAPPDATA\Programs\Python\Launcher\py.exe")
+ 'pwsh.exe' = @()
+ 'cmake.exe' = @((Join-Path $env:ProgramFiles 'CMake\bin\cmake.exe'))
+ 'ninja.exe' = @()
+ # Upstream LLVM. The Documents path is not a typo - see Add-LlvmToUserPath
+ # for why an unelevated install lands there.
+ 'clang-cl.exe' = @(
+ (Join-Path $env:ProgramFiles 'LLVM\bin\clang-cl.exe')
+ (Join-Path $env:LOCALAPPDATA 'Programs\LLVM\bin\clang-cl.exe')
+ (Join-Path ([Environment]::GetFolderPath('MyDocuments')) 'LLVM\bin\clang-cl.exe')
+ )
+ 'dotnet.exe' = @((Join-Path $env:ProgramFiles 'dotnet\dotnet.exe'))
+ 'WinMergeU.exe' = @((Join-Path $env:ProgramFiles 'WinMerge\WinMergeU.exe'), (Join-Path ${env:ProgramFiles(x86)} 'WinMerge\WinMergeU.exe'))
+ 'BinSkim.exe' = @((Join-Path $BinSkimDir 'BinSkim.exe'))
+ 'rsync.exe' = @((Join-Path $RsyncDir 'rsync.exe'))
+ 'ssh.exe' = @((Join-Path $env:WINDIR 'System32\OpenSSH\ssh.exe'))
+ 'nasm.exe' = @()
+ 'iperf3.exe' = @()
+ 'OpenCppCoverage.exe' = @((Join-Path $env:ProgramFiles 'OpenCppCoverage\OpenCppCoverage.exe'), (Join-Path ${env:ProgramFiles(x86)} 'OpenCppCoverage\OpenCppCoverage.exe'))
+ 'vswhere.exe' = @($vsWhereExe)
+ 'xperf.exe' = @((Join-Path ${env:ProgramFiles(x86)} 'Windows Kits\10\Windows Performance Toolkit\xperf.exe'))
+ }
+ if ($vs) {
+ $targets['MSBuild.exe'] = @((Join-Path $vs 'MSBuild\Current\Bin\arm64\MSBuild.exe'), (Join-Path $vs 'MSBuild\Current\Bin\MSBuild.exe'))
+ # The MSVC and VS-Clang compilers, under whichever MSVC version is present.
+ $msvc = Get-ChildItem (Join-Path $vs 'VC\Tools\MSVC') -Directory -ErrorAction SilentlyContinue |
+ Sort-Object Name | Select-Object -Last 1
+ if ($msvc) {
+ $hostDir = if ($IsArm64) { 'Hostarm64\arm64' } else { 'Hostx64\x64' }
+ $targets['cl.exe (MSVC)'] = @((Join-Path $msvc.FullName "bin\$hostDir\cl.exe"))
+ }
+ $llvmHost = if ($IsArm64) { 'ARM64\bin' } else { 'x64\bin' }
+ $targets['clang-cl.exe (VS)'] = @((Join-Path $vs "VC\Tools\Llvm\$llvmHost\clang-cl.exe"))
+ }
+
+ # Tools this box does not provision on ARM64. Dropped from the audit rather
+ # than left to print "- not installed", because that line reads as a gap in
+ # the provisioning when it is the provisioning working as intended - and a
+ # dull audit is one you keep reading.
+ #
+ # The rows survive on x64, where all of these are installed and expected.
+ # Anything still on disk from before the split shows up in the winget list,
+ # not here.
+ if ($IsArm64) {
+ foreach ($gone in 'WinMergeU.exe', 'BinSkim.exe', 'nasm.exe',
+ 'OpenCppCoverage.exe', 'clang-cl.exe', 'clang-cl.exe (VS)') {
+ $targets.Remove($gone)
+ }
+ }
+
+ $native = if ($IsArm64) { 'ARM64' } else { 'x64' }
+ $unexpected = @()
+ foreach ($name in $targets.Keys) {
+ # A LABELLED entry - "clang-cl.exe (VS)" - names one specific copy, so it
+ # is resolved ONLY from its explicit candidates. Falling back to the PATH
+ # there would silently answer with a different installation of the same
+ # tool: with upstream LLVM on the PATH, the "(VS)" row reported the
+ # upstream compiler and so claimed Visual Studio's was present when it was
+ # not. Unlabelled entries still resolve PATH-first, because for those the
+ # question is which binary a build would actually invoke.
+ $exe = ($name -split ' ')[0]
+ $isPinned = $name -ne $exe
+ if ($isPinned) {
+ $path = $targets[$name] | Where-Object { $_ -and (Test-Path $_) } | Select-Object -First 1
+ } else {
+ $path = Resolve-OnPath $exe
+ if (-not $path) { $path = $targets[$name] | Where-Object { $_ -and (Test-Path $_) } | Select-Object -First 1 }
+ }
+ if (-not $path) { Write-Host (" {0,-22} {1}" -f $name, '- not installed') -ForegroundColor DarkGray; continue }
+
+ $mach = Get-PEMachine $path
+ if (-not $mach) { continue }
+ if ($mach -eq $native) {
+ Write-Host (" {0,-22} {1,-6} native" -f $name, $mach) -ForegroundColor Green
+ } elseif ($KnownEmulated.ContainsKey($exe)) {
+ Write-Host (" {0,-22} {1,-6} expected: {2}" -f $name, $mach, $KnownEmulated[$exe]) -ForegroundColor DarkGray
+ } else {
+ Write-Host (" {0,-22} {1,-6} NOT NATIVE - $path" -f $name, $mach) -ForegroundColor Yellow
+ if ($Remedies.ContainsKey($exe)) {
+ Write-Host (" {0,-22} {1,-6} -> {2}" -f '', '', $Remedies[$exe]) -ForegroundColor Yellow
+ }
+ $unexpected += "$name ($mach)"
+ }
+ }
+
+ if ($unexpected) {
+ Write-Warning "Running under emulation with no listed reason: $($unexpected -join ', ')."
+ Write-Warning 'If a native build exists, prefer it (see the -> lines above); otherwise add it to $KnownEmulated with the reason.'
+ } else {
+ Write-Host ' Everything resolved to a native build, or to a listed exception.' -ForegroundColor Green
+ }
+}
+