Build Zig with previous Zig version by parsing devkit.

bZig.ps1

# powershell script to parse devkit version and install Zig
# assume: 1. devkit in dir devkit, zig in dir zig in same dir
#         2. powershell scripts executable (execution in shell):
#         Get-Content bZig.ps1 | PowerShell.exe -noprofile -

# parse pip install
$draftpathninja = pip show ninja
$pathninja = $draftpathninja[7].Split(" ")[1]
$joinpath = -join($pathninja, "\ninja\data\bin")
$env:Path += $joinpath
$joinpath
$env:Path

function CheckLastExitCode {
    if (!$?) {
        exit 1
    }
    return 0
}

# replace with other dir, if needed
$COMMON_DIR = -join('C:\Users\', $env:UserName, '\Desktop')
Set-Location -Path $COMMON_DIR
$line = Get-ChildItem -Path .\zig\ci\x86_64-windows.ps1 -Recurse | Select-String -Pattern 'ZIG_LLVM_CLANG_LLD_NAME ='
$splitted = $line -split "-"
$version_raw = -join($splitted[3], "-", $splitted[4])
$VERSION = $version_raw.Substring(0,$version_raw.Length-1)
$TARGET = "x86_64-windows-gnu"
$ZIG_LLVM_CLANG_LLD_NAME = "zig+llvm+lld+clang-$TARGET-$VERSION"
$MCPU = "baseline"
$DEVKIT = "$(Get-Location)\devkit\$ZIG_LLVM_CLANG_LLD_NAME"
$ZIG = "$PREFIX_PATH\bin\zig.exe"
$ZIG_LIB_DIR = "$(Get-Location)\zig\lib"

Set-Location -Path 'zig'
& $DEVKIT\bin\zig.exe build -p stage3 --search-prefix $DEVKIT --zig-lib-dir lib -Dstatic-llvm -Duse-zig-libcxx -Dtarget=x86_64-windows-gnu
CheckLastExitCode

TODO: fixup overly long default zig paths for devkit to prevent too long lines.
Could be thats the reason why compilation doesnt work.