reviewing project state, doing some tests.

scripts/build.ci.ps1

@@ -10,7 +10,57 @@ $vendor_toolchain   = Join-Path $PSScriptRoot 'helpers/vendor_toolchain.ps1'
 
 Import-Module $misc
 
-$path_root = Get-ScriptRepoRoot
+function stop-stage {
+    param([string]$stage, [int]$code_exit = 1)
+    Write-Host "FAILED: $stage" -ForegroundColor Red
+    exit $code_exit
+}
+
+function invoke-stageTool {
+    param(
+        [string]$stage,
+        [bool]$compiled,
+        [string]$executable,
+        [string]$path_work
+    )
+    if (-not $compiled) {
+        stop-stage "$stage compile/link"
+    }
+    if (-not (Test-Path -LiteralPath $executable)) {
+        stop-stage "$stage missing output $executable"
+    }
+    $code_exit = 1
+    push-location $path_work
+    try {
+        & $executable
+        $code_exit = $LASTEXITCODE
+    }
+    finally {
+        pop-location
+    }
+    if ($code_exit -ne 0) {
+        stop-stage "$stage run" $code_exit
+    }
+    Write-Host "PASSED: $stage"
+}
+
+if ($env:GENCPP_SOURCE_ROOT) {
+    $path_root = (Resolve-Path -LiteralPath $env:GENCPP_SOURCE_ROOT).Path
+    $probe = Join-Path $path_root "base\base.cpp"
+    if (-not (Test-Path -LiteralPath $probe)) {
+        stop-stage "GENCPP_SOURCE_ROOT is not a gencpp tree: $path_root"
+    }
+}
+else {
+    $path_root = Get-ScriptRepoRoot
+}
+Write-Host "SOURCE_ROOT: $path_root"
+if ($null -eq $is_windows) {
+    $is_windows = [System.Environment]::OSVersion.Platform -eq 'Win32NT'
+}
+if ($null -eq $is_linux) {
+    $is_linux = [System.Environment]::OSVersion.Platform -eq 'Unix'
+}
 
 Push-Location $path_root
 
@@ -50,7 +100,7 @@ if ( $args ) { $args | ForEach-Object {
 #endregion Arguments
 
 #region Configuration
-if ($IsWindows) {
+if ($is_windows) {
 	# This library was really designed to only run on 64-bit systems.
 	# (Its a development tool after all)
     & $devshell -arch amd64
@@ -81,7 +131,7 @@ $cannot_build = $cannot_build -and  $c_lib_dyn    -eq $false
 $cannot_build = $cannot_build -and  $unreal       -eq $false
 $cannot_build = $cannot_build -and  $test         -eq $false
 if ( $cannot_build ) {
-	throw "No build target specified. One must be specified, this script will not assume one"
+	Stop-stage "No build target specified"
 }
 
 . $vendor_toolchain
@@ -125,18 +175,7 @@ if ( $base )
 	$executable = join-path $path_build "base.exe"
 
 	$result = build-simple $path_build $includes $compiler_args $linker_args $unit $executable
-
-	Push-Location $path_base
-		if ( Test-Path( $executable ) ) {
-			write-host "`nRunning base"
-			$time_taken = Measure-Command { & $executable
-					| ForEach-Object {
-						write-host `t $_ -ForegroundColor Green
-					}
-				}
-			write-host "`nbase completed in $($time_taken.TotalMilliseconds) ms"
-		}
-	Pop-Location
+	invoke-stageTool -stage "base" -compiled $result -executable $executable -path_work $path_base
 }
 
 if ( $segmented )
@@ -163,18 +202,7 @@ if ( $segmented )
 	$executable = join-path $path_build     "segmented.exe"
 
 	$result = build-simple $path_build $includes $compiler_args $linker_args $unit $executable
-
-	Push-Location $path_segmented
-		if ( Test-Path( $executable ) ) {
-			write-host "`nRunning segmented"
-			$time_taken = Measure-Command { & $executable
-					| ForEach-Object {
-						write-host `t $_ -ForegroundColor Green
-					}
-				}
-			write-host "`nSegmented completed in $($time_taken.TotalMilliseconds) ms"
-		}
-	Pop-Location
+	invoke-stageTool -stage "segmented" -compiled $result -executable $executable -path_work $path_segmented
 }
 
 if ( $singleheader )
@@ -201,18 +229,7 @@ if ( $singleheader )
 	)
 
 	$result = build-simple $path_build $includes $compiler_args $linker_args $unit $executable
-
-	Push-Location $path_singleheader
-		if ( Test-Path( $executable ) ) {
-			write-host "`nRunning singleheader generator"
-			$time_taken = Measure-Command { & $executable
-					| ForEach-Object {
-						write-host `t $_ -ForegroundColor Green
-					}
-				}
-			write-host "`nSingleheader generator completed in $($time_taken.TotalMilliseconds) ms"
-		}
-	Pop-Location
+	invoke-stageTool -stage "singleheader" -compiled $result -executable $executable -path_work $path_singleheader
 }
 
 if ( $c_lib -or $c_lib_static -or $c_lib_dyn )
@@ -239,18 +256,7 @@ if ( $c_lib -or $c_lib_static -or $c_lib_dyn )
 	)
 
 	$result = build-simple $path_build $includes $compiler_args $linker_args $unit $executable
-
-	Push-Location $path_c_library
-		if ( Test-Path( $executable ) ) {
-			write-host "`nRunning c_library generator"
-			$time_taken = Measure-Command { & $executable
-					| ForEach-Object {
-						write-host `t $_ -ForegroundColor Green
-					}
-				}
-			write-host "`nc_library generator completed in $($time_taken.TotalMilliseconds) ms"
-		}
-	Pop-Location
+	invoke-stageTool -stage "c_lib" -compiled $result -executable $executable -path_work $path_c_library
 }
 
 if ( $c_lib_static )
@@ -267,6 +273,7 @@ if ( $c_lib_static )
 
 	$linker_args = @()
 	$result = build-simple $path_build $includes $compiler_args $linker_args $unit $path_lib
+	if (-not $result) { Stop-stage "c_lib_static compile/link" }
 }
 
 if ( $c_lib_dyn )
@@ -285,6 +292,7 @@ if ( $c_lib_dyn )
  
 	$linker_args = @()
 	$result = build-simple $path_build $includes $compiler_args $linker_args $unit $path_dll
+	if (-not $result) { Stop-stage "c_lib_dyn compile/link" }
 }
 
 if ( $unreal )
@@ -311,23 +319,27 @@ if ( $unreal )
 	)
 
 	$result = build-simple $path_build $includes $compiler_args $linker_args $unit $executable
-
-	Push-Location $path_unreal
-		if ( Test-Path( $executable ) ) {
-			write-host "`nRunning unreal variant generator"
-			$time_taken = Measure-Command { & $executable
-					| ForEach-Object {
-						write-host `t $_ -ForegroundColor Green
-					}
-				}
-			write-host "`n Unreal variant generator completed in $($time_taken.TotalMilliseconds) ms"
-		}
-	Pop-Location
+	invoke-stageTool -stage "unreal" -compiled $result -executable $executable -path_work $path_unreal
 
 	. $refactor_unreal
 }
 
 # C Library testing
+if ($test) {
+    $consumer_headers = @(
+        (Join-Path $path_c_library 'gen\gen_singleheader.h'),
+        (Join-Path $path_singleheader 'gen\gen.hpp')
+    )
+    $header_hashes_before = @{}
+    foreach ($header in $consumer_headers) {
+        if (-not (Test-Path -LiteralPath $header -PathType Leaf)) {
+            Stop-stage "test missing generated header $header"
+        }
+        $header_hashes_before[$header] = (Get-FileHash -LiteralPath $header -Algorithm SHA256).Hash
+        Write-Host "HEADER_SHA256_GENERATED: $($header_hashes_before[$header]) $header"
+    }
+}
+
 if ( $test -and $true )
 {
 	$path_test_c = join-path $path_test   c_library
@@ -350,24 +362,14 @@ if ( $test -and $true )
 	$compiler_args += $flag_all_c
 	$compiler_args += $flag_updated_cpp_macro
 	$compiler_args += $flag_c11
+	$compiler_args += "-H"
 
 	$linker_args   = @(
 		$flag_link_win_subsystem_console
 	)
 
 	$result = build-simple $path_build $includes $compiler_args $linker_args $unit $executable
-
-	Push-Location $path_test_c
-		if ( Test-Path( $executable ) ) {
-			write-host "`nRunning c_library test"
-			$time_taken = Measure-Command { & $executable
-					| ForEach-Object {
-						write-host `t $_ -ForegroundColor Green
-					}
-				}
-			write-host "`nc_library generator completed in $($time_taken.TotalMilliseconds) ms"
-		}
-	Pop-Location
+	invoke-stageTool -stage "test-c11" -compiled $result -executable $executable -path_work $path_test_c
 }
 
 if ( $test -and $false )
@@ -398,30 +400,18 @@ if ( $test -and $false )
 	)
 
 	$result = build-simple $path_build $includes $compiler_args $linker_args $unit $executable
-
-	Push-Location $path_test_c
-		if ( Test-Path( $executable ) ) {
-			write-host "`nRunning c_library test"
-			$time_taken = Measure-Command { & $executable
-					| ForEach-Object {
-						write-host `t $_ -ForegroundColor Green
-					}
-				}
-			write-host "`nc_library generator completed in $($time_taken.TotalMilliseconds) ms"
-		}
-	Pop-Location
 }
 
-if ($test -and $false)
+if ($test)
 {
 	$path_test_cpp = join-path $path_test     cpp_library
 	$path_build    = join-path $path_test_cpp build
 	$path_gen      = join-path $path_test_cpp gen
 	if ( -not(Test-Path($path_build) )) {
-		New-Item -ItemType Directory -Path $path_build
+		new-item -ItemType Directory -Path $path_build
 	}
 	if ( -not(Test-Path($path_gen) )) {
-		New-Item -ItemType Directory -Path $path_gen
+		new-item -ItemType Directory -Path $path_gen
 	}
 
 	$path_singleheader_include = join-path $path_singleheader gen
@@ -431,25 +421,29 @@ if ($test -and $false)
 
 	$compiler_args = @()
 	$compiler_args += ( $flag_define + 'GEN_TIME' )
+	$compiler_args += @("-x", "c++")
+	$compiler_args += "-std=c++17"
+	$compiler_args += ($flag_define + "GEN_BUILD_DEBUG=1")
+	$compiler_args += "-H"
 
 	$linker_args   = @(
 		$flag_link_win_subsystem_console
 	)
 
 	$result = build-simple $path_build $includes $compiler_args $linker_args $unit $executable
-
-	Push-Location $path_test_cpp
-		if ( Test-Path( $executable ) ) {
-			write-host "`nRunning cpp_library test"
-			$time_taken = Measure-Command { & $executable
-					| ForEach-Object {
-						write-host `t $_ -ForegroundColor Green
-					}
-				}
-			write-host "`nc_library generator completed in $($time_taken.TotalMilliseconds) ms"
-		}
-	Pop-Location
+	invoke-stageTool -stage "test-cpp" -compiled $result -executable $executable -path_work $path_test_cpp
+}
+if ($test) {
+    foreach ($header in $consumer_headers) {
+        $hash = (Get-FileHash -LiteralPath $header -Algorithm SHA256).Hash
+        write-host "HEADER_SHA256_CONSUMED: $hash $header"
+        if ($hash -ne $header_hashes_before[$header]) {
+            Stop-stage "test header changed after generation $header"
+        }
+    }
 }
 #endregion Building
 
-Pop-Location # $path_root
+pop-location # $path_root
+write-host "PASSED: build.ci.ps1"
+exit 0

scripts/build.ps1

@@ -1,3 +1,3 @@
-cls
 $build = Join-Path $PSScriptRoot 'build.ci.ps1'
 & $build @args
+exit $LASTEXITCODE

scripts/helpers/vendor_toolchain.ps1

@@ -3,7 +3,7 @@
 
   import-module $target_arch
 
-if ($IsWindows) {
+if ($is_windows) {
 	# This HandmadeHero implementation is only designed for 64-bit systems
     & $devshell -arch amd64
 }
@@ -27,6 +27,12 @@ function run-archiver
 {
     param( $archiver, $library, $lib_args )
 
+    if (-not (Get-Command $archiver -ErrorAction SilentlyContinue)) {
+        Write-Host "FAILED: archiver launch $archiver" -ForegroundColor Red
+        return $false
+    }
+    Write-Host ("ARCHIVER_ARGV: " + ($lib_args -join " "))
+
     write-host "`Creating library $library"
     if ( $verbose ) {
         write-host "Lib manager config:"
@@ -60,9 +66,15 @@ function run-compiler
 {
 	param( $compiler, $unit, $compiler_args )
 
+	if (-not (Get-Command $compiler -ErrorAction SilentlyContinue)) {
+		Write-Host "FAILED: compiler launch $compiler" -ForegroundColor Red
+		return $false
+	}
+
 	if ( $analysis ) {
 		$compiler_args += $flag_syntax_only
 	}
+	Write-Host ("COMPILER_ARGV: " + ($compiler_args -join " "))
 
 	write-host "`Compiling $unit"
 	if ( $verbose ) {
@@ -97,6 +109,12 @@ function run-linker
 {
 	param( $linker, $binary, $linker_args )
 
+	if (-not (Get-Command $linker -ErrorAction SilentlyContinue)) {
+		Write-Host "FAILED: linker launch $linker" -ForegroundColor Red
+		return $false
+	}
+	Write-Host ("LINKER_ARGV: " + ($linker_args -join " "))
+
 	write-host "`Linking $binary"
 	if ( $verbose ) {
 		write-host "Linker config:"
@@ -147,12 +165,12 @@ if ( $vendor -match "clang" )
 	$flag_library					   = '-l'
 	$flag_library_path				   = '-L'
 	$flag_linker                       = '-Wl,'
-	if ( $IsWindows ) {
+	if ( $is_windows ) {
 		$flag_link_dll                 = '/DLL'
 		$flag_link_mapfile 		       = '/MAP:'
 		$flag_link_optimize_references = '/OPT:REF'
 	}
-	if ( $IsLinux ) {
+	if ( $is_linux ) {
 		$flag_link_mapfile              = '--Map='
 		$flag_link_optimize_references  = '--gc-sections'
 	}
@@ -191,7 +209,7 @@ if ( $vendor -match "clang" )
 	)
 
 	# https://learn.microsoft.com/en-us/cpp/c-runtime-library/crt-library-features?view=msvc-170
-	if ( $IsWindows ) {
+	if ( $is_windows ) {
 		$libraries = @(
 			'Kernel32' # For Windows API
 			# 'msvcrt', # For the C Runtime (Dynamically Linked)

scripts/verify_baseline.ps1

@@ -0,0 +1,267 @@
+param(
+    [Parameter(Mandatory = $true)][Alias('MirrorRoot')][string]$path_mirror,
+    [ValidateSet(
+		"measure",
+		"positive",
+		"negative-compile",
+		"negative-link",
+		"negative-launch",
+		"negative-stale",
+		"negative-stale-header",
+		"negative-format",
+		"negative-refactor",
+		"negative-assert"
+	)]
+    [string]$mode = "positive",
+    [Alias('SourceRoot')][string]$path_source_root = "C:\projects\gencpp",
+    [Alias('ReuseMirror')][switch]$reuse_mirror
+)
+
+$ErrorActionPreference = "Stop"
+$path_source           = (Resolve-Path -LiteralPath $path_source_root).Path
+$path_mirror           = [System.IO.Path]::GetFullPath($path_mirror)
+$path_verification_root = Join-Path $path_mirror 'test\verification'
+if ($path_mirror -eq $path_source) { throw "MirrorRoot must not be the project checkout" }
+$prefix_source = $path_source.TrimEnd('\') + '\'
+$prefix_mirror = $path_mirror.TrimEnd('\') + '\'
+if ($path_source.StartsWith($prefix_mirror, [System.StringComparison]::OrdinalIgnoreCase) -or
+    $path_mirror.StartsWith($prefix_source, [System.StringComparison]::OrdinalIgnoreCase)) {
+    throw "path_mirror and path_source_root must not overlap"
+}
+if ($reuse_mirror -and $mode -ne "positive") { throw "reuse_mirror is for the positive mode only" }
+if ($reuse_mirror -and -not (Test-Path -LiteralPath (Join-Path $path_mirror 'base\base.cpp'))) {
+    throw "reuse_mirror needs an existing baseline mirror"
+}
+
+function Copy-Snapshot([string]$path_destination) 
+{
+    if (Test-Path -LiteralPath $path_destination) { Remove-Item -LiteralPath $path_destination -Recurse -Force }
+    New-Item -ItemType Directory -Path $path_destination | Out-Null
+    & robocopy $path_source $path_destination /E /NFL /NDL /NJH /NJS /XD .git
+    if ($LASTEXITCODE -ge 8) { throw "robocopy failed: $LASTEXITCODE" }
+    $global:LASTEXITCODE = 0
+    @(
+        "gen_segmented\gen",
+		"gen_segmented\build",
+        "gen_singleheader\gen",
+		"gen_singleheader\build",
+        "gen_c_library\gen",
+		"gen_c_library\build",
+        "gen_unreal_engine\gen",
+		"gen_unreal_engine\build",
+        "test\c_library\build",
+		"test\c_library\gen",
+        "test\cpp_library\build",
+		"test\cpp_library\gen",
+        "base\build"
+    ) | ForEach-Object {
+        $path_item = Join-Path $path_destination $_
+        if (Test-Path -LiteralPath $path_item) { Remove-Item -LiteralPath $path_item -Recurse -Force }
+    }
+}
+
+function Copy-VerificationFixture([string]$name_fixture, [string]$path_destination) {
+    $path_fixture = Join-Path $path_verification_root $name_fixture
+    if (-not (Test-Path -LiteralPath $path_fixture -PathType Leaf)) {
+        throw "Missing verification fixture: $path_fixture"
+    }
+    Copy-Item -LiteralPath $path_fixture -Destination $path_destination -Force
+}
+
+function Invoke-Driver([string]$path_tree, [string[]]$list_targets) {
+    $path_driver = Join-Path $path_tree "scripts\build.ci.ps1"
+    $name_log = if ($reuse_mirror) { 'verify_driver.repeat.log' } else { 'verify_driver.log' }
+    $path_log = Join-Path $path_tree $name_log
+    $path_previous_root = $env:GENCPP_SOURCE_ROOT
+    $env:GENCPP_SOURCE_ROOT = $path_tree
+    $line_args = $list_targets -join ' '
+    try {
+        $text_output = & powershell.exe -NoProfile -Command "& '$path_driver' clang debug $line_args; exit `$LASTEXITCODE" *>&1
+        $code_exit = $LASTEXITCODE
+    }
+    finally {
+        $env:GENCPP_SOURCE_ROOT = $path_previous_root
+    }
+    $text_output | Tee-Object -FilePath $path_log | Out-Host
+    $script:path_last_driver_log  = $path_log
+    $script:code_last_driver = $code_exit
+    return $code_exit
+}
+
+function Get-DriverLogText {
+    if (-not $script:path_last_driver_log) { return "" }
+    if (-not (Test-Path -LiteralPath $script:path_last_driver_log)) { return "" }
+    return Get-Content -LiteralPath $script:path_last_driver_log -Raw
+}
+
+function Assert-PositiveOutputs([string]$path_tree) {
+    $list_outputs = @(
+        'base\components\gen\ecodetypes.hpp', 
+		'base\components\gen\eoperator.hpp',
+        'base\components\gen\especifier.hpp', 
+		'base\components\gen\etoktype.hpp',
+        'base\components\gen\ast_inlines.hpp',
+        'gen_segmented\gen\gen.hpp',
+		'gen_segmented\gen\gen.cpp',
+        'gen_segmented\gen\gen.dep.hpp',
+		'gen_segmented\gen\gen.dep.cpp',
+        'gen_segmented\gen\gen.builder.hpp',
+		'gen_segmented\gen\gen.builder.cpp',
+        'gen_segmented\gen\gen.scanner.hpp',
+		'gen_segmented\gen\gen.scanner.cpp',
+        'gen_singleheader\gen\gen.hpp',
+        'gen_c_library\gen\gen.h',
+		'gen_c_library\gen\gen.c',
+        'gen_c_library\gen\gen.dep.h',
+		'gen_c_library\gen\gen.dep.c',
+        'gen_c_library\gen\gen_singleheader.h'
+    )
+    $list_hashes = foreach ($path_relative in $list_outputs) {
+        $path_output = Join-Path $path_tree $path_relative
+        if (-not (Test-Path -LiteralPath $path_output -PathType Leaf)) { throw "Missing output: $path_output" }
+        if ((Get-Item -LiteralPath $path_output).Length -eq 0) { throw "Empty output: $path_output" }
+        "{0}  {1}" -f (Get-FileHash -LiteralPath $path_output -Algorithm SHA256).Hash, $path_relative
+    }
+    $text_log = (Get-DriverLogText).Replace('\\', '\')
+    foreach ($path_relative in @('gen_singleheader\gen\gen.hpp', 'gen_c_library\gen\gen_singleheader.h')) {
+        $path_header = Join-Path $path_tree $path_relative
+        if ($text_log -notmatch [regex]::Escape($path_header)) { throw "Compiler trace missing $path_header" }
+    }
+    $name_hash_file = if ($reuse_mirror) { 'verify_outputs.repeat.sha256' } else { 'verify_outputs.sha256' }
+    $list_hashes | Set-Content -LiteralPath (Join-Path $path_tree $name_hash_file)
+    Write-Host "PASSED: outputs and consumer header traces ($name_hash_file)"
+}
+
+$list_targets = @("base", "segmented", "singleheader", "c_lib", "test")
+if (-not $reuse_mirror) { Copy-Snapshot $path_mirror }
+
+if ($mode -eq "measure" -or $mode -eq "positive") {
+    $code_exit = Invoke-Driver $path_mirror $list_targets
+    if ($mode -eq "positive" -and $code_exit -ne 0) { exit $code_exit }
+    if ($mode -eq "positive") { Assert-PositiveOutputs $path_mirror }
+    exit $code_exit
+}
+
+if ($mode -eq "negative-compile") {
+    Copy-VerificationFixture 'failure_compile.cpp' (Join-Path $path_mirror 'base\base.cpp')
+    $code_exit = Invoke-Driver $path_mirror @("base")
+    if ($code_exit -eq 0) { throw "negative-compile returned 0" }
+    exit 0
+}
+
+if ($mode -eq "negative-link") {
+    Copy-VerificationFixture 'failure_link.cpp' (Join-Path $path_mirror 'base\base.cpp')
+    $code_exit = Invoke-Driver $path_mirror @("base")
+    $text_log = Get-DriverLogText
+    if ($code_exit -eq 0 -or $text_log -notmatch "Linking failed") {
+        throw "negative-link did not fail at the linker"
+    }
+    exit 0
+}
+
+if ($mode -eq "negative-launch") {
+    $path_toolchain = Join-Path $path_mirror "scripts\helpers\vendor_toolchain.ps1"
+    $text_toolchain = Get-Content -LiteralPath $path_toolchain -Raw
+    $text_patched   = $text_toolchain.Replace(
+		"`$linker = 'lld-link'",
+		"`$linker = 'gencpp-missing-linker'"
+	)
+    if ($text_patched -eq $text_toolchain) { throw "negative-launch could not replace the linker path" }
+
+    Set-Content -LiteralPath $path_toolchain -Value $text_patched -NoNewline
+    $code_exit = Invoke-Driver $path_mirror @("base")
+    $text_log  = Get-DriverLogText
+    if ($code_exit -eq 0 -or $text_log -notmatch "FAILED: linker launch gencpp-missing-linker") {
+        throw "negative-launch did not report a missing linker"
+    }
+    exit 0
+}
+
+if ($mode -eq "negative-stale") {
+    $path_stale_source     = Join-Path $path_mirror "stale_marker.c"
+    $path_stale_executable = Join-Path $path_mirror "stale_marker.exe"
+    Copy-VerificationFixture 'stale_executable.c' $path_stale_source
+
+    & clang -o $path_stale_executable $path_stale_source
+    if ($LASTEXITCODE -ne 0) { throw "failed to compile stale marker" }
+
+    $path_base_build = Join-Path $path_mirror "base\build"
+    New-Item -ItemType Directory -Path $path_base_build -Force | Out-Null
+    Copy-Item -LiteralPath $path_stale_executable -Destination (Join-Path $path_base_build "base.exe") -Force
+    Copy-VerificationFixture 'failure_compile.cpp' (Join-Path $path_mirror 'base\base.cpp')
+
+    $code_exit = Invoke-Driver $path_mirror @("base")
+    if ($code_exit -eq 0)  { throw "negative-stale returned 0" }
+    if ($code_exit -eq 73) { throw "negative-stale ran the stale executable" }
+    exit 0
+}
+
+if ($mode -eq "negative-stale-header") {
+    $code_exit = Invoke-Driver $path_mirror @("base", "segmented", "singleheader", "c_lib")
+    if ($code_exit -ne 0) { throw "negative-stale-header setup generation failed: $code_exit" }
+
+    Copy-Item -LiteralPath $script:path_last_driver_log -Destination (Join-Path $path_mirror 'verify_driver.setup.log')
+    $path_header = Join-Path $path_mirror 'gen_c_library\gen\gen_singleheader.h'
+    if (-not (Test-Path -LiteralPath $path_header)) { throw 'negative-stale-header missing setup header' }
+
+    Copy-VerificationFixture 'failure_compile.cpp' (Join-Path $path_mirror 'gen_c_library\c_library.cpp')
+    $code_exit = Invoke-Driver $path_mirror @('c_lib', 'test')
+    $text_log  = Get-DriverLogText
+    if ($code_exit -eq 0 -or $text_log -notmatch 'FAILED: c_lib compile/link') {
+        throw 'negative-stale-header did not fail at c_lib'
+    }
+    if ($text_log -match 'Compiling .*test[.]c|PASSED: test-c11|PASSED: test-cpp') {
+        throw 'negative-stale-header consumed a prior header'
+    }
+    exit 0
+}
+
+if ($mode -eq "negative-format") {
+    $path_fake_tools = Join-Path $path_mirror "fake-tools"
+    New-Item -ItemType Directory -Path $path_fake_tools -Force | Out-Null
+    Copy-VerificationFixture 'failure_format.cmd' (Join-Path $path_fake_tools 'clang-format.cmd')
+    $path_saved = $env:PATH
+    $env:PATH   = "$path_fake_tools;$env:PATH"
+    try {
+        $code_exit = Invoke-Driver $path_mirror @("base")
+    }
+    finally {
+        $env:PATH = $path_saved
+    }
+    $text_log = Get-DriverLogText
+    if ($code_exit -eq 0)                          { throw "negative-format returned 0" }
+    if ($text_log -notmatch "clang-format failed") { throw "negative-format log missing clang-format failed" }
+    exit 0
+}
+
+if ($mode -eq "negative-refactor") {
+    $path_fake_source     = Join-Path $path_mirror 'failing_refactor.c'
+    $path_fake_executable = Join-Path $path_mirror 'scripts\helpers\refactor.exe'
+    Copy-VerificationFixture 'failure_refactor.c' $path_fake_source
+    & clang -o $path_fake_executable $path_fake_source
+    if ($LASTEXITCODE -ne 0) { throw 'negative-refactor failed to compile the stub' }
+
+    $code_exit = Invoke-Driver $path_mirror @('c_lib')
+    $text_log  = Get-DriverLogText
+    if ($code_exit -eq 0 -or $text_log -notmatch 'refactor failed') {
+        throw 'negative-refactor did not propagate subprocess failure'
+    }
+    exit 0
+}
+
+if ($mode -eq "negative-assert") {
+    $path_header = Join-Path $path_mirror "gen_singleheader\gen\gen.hpp"
+    if (-not (Test-Path -LiteralPath $path_header)) {
+        $code_exit = Invoke-Driver $path_mirror $list_targets
+        if ($code_exit -ne 0) { throw "negative-assert setup generation failed: $code_exit" }
+    }
+
+    Copy-VerificationFixture 'failure_assert.cpp' (Join-Path $path_mirror 'test\cpp_library\test.cpp')
+    $code_exit = Invoke-Driver $path_mirror @("test")
+    $text_log  = Get-DriverLogText
+    if ($code_exit -eq 0)                            { throw "negative-assert returned 0" }
+    if ($text_log -notmatch "FAIL forced assertion") { throw "negative-assert log missing forced assertion marker" }
+    exit 0
+}
+
+throw "unhandled mode $mode"