Download MSVC compiler/linker & Windows SDK without installing full Visual Studio

!README.md

This downloads standalone 64-bit MSVC compiler, linker & other tools, also headers/libraries from Windows SDK into portable folder, without installing Visual Studio. Has bare minimum components - no UWP/Store/WindowsRT stuff, just files & tools for 64-bit native desktop app development.

Run python.exe portable-msvc.py and it will download output into msvc folder. By default it will download latest available MSVC & Windows SDK - currently v14.32.17.2 and v10.0.22621.0.

You can list available versions with python.exe portable-msvc.py --show-versions and then pass versions you want with --msvc-version and --sdk-version arguments.

To use cl.exe/link.exe from output folder, first run setup.bat - after that PATH/INCLUDE/LIB env variables will be setup to use all the tools as usual. You can also use clang-cl.exe with these includes & libraries.

To use clang-cl.exe without running setup.bat, pass extra /winsysroot msvc argument (msvc is folder name where output is stored).

---

I more or less merged some quality of life features from CrendKing's fork and the comments.

portable-msvc.py

#!/usr/bin/env python3

import io
import os
import sys
import json
import shutil
import hashlib
import zipfile
import tempfile
import argparse
import subprocess
import urllib.request
import urllib.error
from pathlib import Path

OUTPUT = Path("MSVC") # output folder
TEMP = Path(OUTPUT).absolute()

# other architectures may work or may not - not really tested
HOST   = "x64" # or x86
TARGET = "x64" # or x86, arm, arm64

MANIFEST_URL = "https://aka.ms/vs/17/release/channel"

ssl_context = None

def download(url):
  with urllib.request.urlopen(url, context=ssl_context) as res:
    return res.read()

def download_progress(url, check, name, f):
  data = io.BytesIO()
  with urllib.request.urlopen(url, context=ssl_context) as res:
    total = int(res.headers["Content-Length"])
    size = 0
    while True:
      block = res.read(1<<20)
      if not block:
        break
      f.write(block)
      data.write(block)
      size += len(block)
      perc = size * 100 // total
      print(f"\r{name} ... {perc}%", end="")
  print()
  data = data.getvalue()
  digest = hashlib.sha256(data).hexdigest()
  if check.lower() != digest:
    sys.exit(f"Hash mismatch for f{pkg}")
  return data

# super crappy msi format parser just to find required .cab files
def get_msi_cabs(msi):
  index = 0
  while True:
    index = msi.find(b".cab", index+4)
    if index < 0:
      return
    yield msi[index-32:index+4].decode("ascii")

def first(items, cond):
  return next(item for item in items if cond(item))


### parse command-line arguments

ap = argparse.ArgumentParser()
ap.add_argument("--show-versions", const=True, action="store_const", help="Show available MSVC and Windows SDK versions")
ap.add_argument("--accept-license", const=True, action="store_const", help="Automatically accept license")
ap.add_argument("--msvc-version", help="Get specific MSVC version")
ap.add_argument("--sdk-version", help="Get specific Windows SDK version")
args = ap.parse_args()


### get main manifest

try:
  manifest = json.loads(download(MANIFEST_URL))
except urllib.error.URLError as err:
  import ssl
  if isinstance(err.args[0], ssl.SSLCertVerificationError):
    # for more info about Python & issues with Windows certificates see https://stackoverflow.com/a/52074591
    print("ERROR: ssl certificate verification error")
    try:
      import certifi
    except ModuleNotFoundError:
      print("ERROR: please install 'certifi' package to use Mozilla certificates")
      print("ERROR: or update your Windows certs, see instructions here: https://woshub.com/updating-trusted-root-certificates-in-windows-10/#h2_3")
      sys.exit()
    print("NOTE: retrying with certifi certificates")
    ssl_context = ssl.create_default_context(cafile=certifi.where())
    manifest = json.loads(download(MANIFEST_URL))
  else:
    raise


### download VS manifest

vs = first(manifest["channelItems"], lambda x: x["id"] == "Microsoft.VisualStudio.Manifests.VisualStudio")
payload = vs["payloads"][0]["url"]

vsmanifest = json.loads(download(payload))


### find MSVC & WinSDK versions

packages = {}
for p in vsmanifest["packages"]:
  packages.setdefault(p["id"].lower(), []).append(p)

msvc = {}
sdk = {}

for pid,p in packages.items():
  if pid.startswith("Microsoft.VisualStudio.Component.VC.".lower()) and pid.endswith(".x86.x64".lower()):
    pver = ".".join(pid.split(".")[4:6])
    if pver[0].isnumeric():
      msvc[pver] = pid
  elif pid.startswith("Microsoft.VisualStudio.Component.Windows10SDK.".lower()) or \
       pid.startswith("Microsoft.VisualStudio.Component.Windows11SDK.".lower()):
    pver = pid.split(".")[-1]
    if pver.isnumeric():
      sdk[pver] = pid

if args.show_versions:
  print("MSVC versions:", " ".join(sorted(msvc.keys())))
  print("Windows SDK versions:", " ".join(sorted(sdk.keys())))
  sys.exit(0)

msvc_ver = args.msvc_version or max(sorted(msvc.keys()))
sdk_ver = args.sdk_version or max(sorted(sdk.keys()))

if msvc_ver in msvc:
  msvc_pid = msvc[msvc_ver]
  msvc_ver = ".".join(msvc_pid.split(".")[4:-2])
else:
  sys.exit(f"Unknown MSVC version: f{args.msvc_version}")

if sdk_ver in sdk:
  sdk_pid = sdk[sdk_ver]
else:
  sys.exit(f"Unknown Windows SDK version: f{args.sdk_version}")

print(f"Downloading MSVC v{msvc_ver} and Windows SDK v{sdk_ver}")


### agree to license

tools = first(manifest["channelItems"], lambda x: x["id"] == "Microsoft.VisualStudio.Product.BuildTools")
resource = first(tools["localizedResources"], lambda x: x["language"] == "en-us")
license = resource["license"]

if not args.accept_license:
  accept = input(f"Do you accept Visual Studio license at {license} [Y/N] ? ")
  if not accept or accept[0].lower() != "y":
    sys.exit(0)

OUTPUT.mkdir(exist_ok=True)
total_download = 0

### download MSVC

msvc_packages = [
  # MSVC binaries
  f"microsoft.vc.{msvc_ver}.tools.host{HOST}.target{TARGET}.base",
  f"microsoft.vc.{msvc_ver}.tools.host{HOST}.target{TARGET}.res.base",
  # MSVC headers
  f"microsoft.vc.{msvc_ver}.crt.headers.base",
  # MSVC libs
  f"microsoft.vc.{msvc_ver}.crt.{TARGET}.desktop.base",
  f"microsoft.vc.{msvc_ver}.crt.{TARGET}.store.base",
  # MSVC runtime source
  f"microsoft.vc.{msvc_ver}.crt.source.base",
  # ASAN
  f"microsoft.vc.{msvc_ver}.asan.headers.base",
  f"microsoft.vc.{msvc_ver}.asan.{TARGET}.base",
  # MSVC redist
  #f"microsoft.vc.{msvc_ver}.crt.redist.x64.base",
]

for pkg in msvc_packages:
  p = first(packages[pkg], lambda p: p.get("language") in (None, "en-US"))
  for payload in p["payloads"]:
    with tempfile.TemporaryFile(dir=TEMP) as f:
      data = download_progress(payload["url"], payload["sha256"], pkg, f)
      total_download += len(data)
      with zipfile.ZipFile(f) as z:
        for name in z.namelist():
          if name.startswith("Contents/"):
            out = OUTPUT / Path(name).relative_to("Contents")
            out.parent.mkdir(parents=True, exist_ok=True)
            out.write_bytes(z.read(name))


### download Windows SDK

sdk_packages = [
  # Windows SDK tools (like rc.exe & mt.exe)
  f"Windows SDK for Windows Store Apps Tools-x86_en-us.msi",
  # Windows SDK headers
  f"Windows SDK for Windows Store Apps Headers-x86_en-us.msi",
  f"Windows SDK Desktop Headers x86-x86_en-us.msi",
  # Windows SDK libs
  f"Windows SDK for Windows Store Apps Libs-x86_en-us.msi",
  f"Windows SDK Desktop Libs {TARGET}-x86_en-us.msi",
  # CRT headers & libs
  f"Universal CRT Headers Libraries and Sources-x86_en-us.msi",
  # CRT redist
  #"Universal CRT Redistributable-x86_en-us.msi",
]

with tempfile.TemporaryDirectory(dir=TEMP) as d:
  dst = Path(d)

  sdk_pkg = packages[sdk_pid][0]
  sdk_pkg = packages[first(sdk_pkg["dependencies"], lambda x: True).lower()][0]

  msi = []
  cabs = []

  # download msi files
  for pkg in sdk_packages:
    payload = first(sdk_pkg["payloads"], lambda p: p["fileName"] == f"Installers\\{pkg}")
    msi.append(dst / pkg)
    with open(dst / pkg, "wb") as f:
      data = download_progress(payload["url"], payload["sha256"], pkg, f)
      total_download += len(data)
      cabs += list(get_msi_cabs(data))

  # download .cab files
  for pkg in cabs:
    payload = first(sdk_pkg["payloads"], lambda p: p["fileName"] == f"Installers\\{pkg}")
    with open(dst / pkg, "wb") as f:
      data = download_progress(payload["url"], payload["sha256"], pkg, f)
      total_download += len(data)

  print("Unpacking msi files...")

  # run msi installers
  for m in msi:
    subprocess.check_call(["msiexec.exe", "/a", m, "/quiet", "/qn", f"TARGETDIR={OUTPUT.resolve()}"])


### versions

msvcv = list((OUTPUT / "VC/Tools/MSVC").glob("*"))[0].name
sdkv = list((OUTPUT / "Windows Kits/10/bin").glob("*"))[0].name


# place debug CRT runtime files into MSVC folder (not what real Visual Studio installer does... but is reasonable)

dst = OUTPUT / "VC/Tools/MSVC" / msvcv / f"bin/Host{HOST}/{TARGET}"

with tempfile.TemporaryDirectory(dir=TEMP) as d:
  d = Path(d)
  pkg = "microsoft.visualcpp.runtimedebug.14"
  dbg = first(packages[pkg], lambda p: p["chip"] == HOST)
  for payload in dbg["payloads"]:
    name = payload["fileName"]
    with open(d / name, "wb") as f:
      data = download_progress(payload["url"], payload["sha256"], f"{pkg}/{name}", f)
      total_download += len(data)
  msi = d / first(dbg["payloads"], lambda p: p["fileName"].endswith(".msi"))["fileName"]

  with tempfile.TemporaryDirectory(dir=TEMP) as d2:
    subprocess.check_call(["msiexec.exe", "/a", str(msi), "/quiet", "/qn", f"TARGETDIR={d2}"])
    for f in first(Path(d2).glob("System*"), lambda x: True).iterdir():
      f.replace(dst / f.name)

# download DIA SDK and put msdia140.dll file into MSVC folder

with tempfile.TemporaryDirectory(dir=TEMP) as d:
  d = Path(d)
  pkg = "microsoft.visualc.140.dia.sdk.msi"
  dia = packages[pkg][0]
  for payload in dia["payloads"]:
    name = payload["fileName"]
    with open(d / name, "wb") as f:
      data = download_progress(payload["url"], payload["sha256"], f"{pkg}/{name}", f)
      total_download += len(data)
  msi = d / first(dia["payloads"], lambda p: p["fileName"].endswith(".msi"))["fileName"]

  with tempfile.TemporaryDirectory(dir=TEMP) as d2:
    subprocess.check_call(["msiexec.exe", "/a", str(msi), "/quiet", "/qn", f"TARGETDIR={d2}"])

    if HOST == "x86": msdia = "msdia140.dll"
    elif HOST == "x64": msdia = "amd64/msdia140.dll"
    else: sys.exit("unknown")

    src = Path(d2) / "Program Files" / "Microsoft Visual Studio 14.0" / "DIA SDK" / "bin" / msdia
    src.replace(dst / "msdia140.dll")


### cleanup

shutil.rmtree(OUTPUT / "Common7", ignore_errors=True)
for f in ["Auxiliary", f"lib/{TARGET}/store", f"lib/{TARGET}/uwp"]:
  shutil.rmtree(OUTPUT / "VC/Tools/MSVC" / msvcv / f)
for f in OUTPUT.glob("*.msi"):
  f.unlink()
for f in ["Catalogs", "DesignTime", f"bin/{sdkv}/chpe", f"Lib/{sdkv}/ucrt_enclave"]:
  shutil.rmtree(OUTPUT / "Windows Kits/10" / f, ignore_errors=True)
for arch in ["x86", "x64", "arm", "arm64"]:
  if arch != TARGET:
    shutil.rmtree(OUTPUT / "Windows Kits/10/Lib" / sdkv / "ucrt" / arch)
    shutil.rmtree(OUTPUT / "Windows Kits/10/Lib" / sdkv / "um" / arch)
  if arch != HOST:
    shutil.rmtree(OUTPUT / "Windows Kits/10/bin" / sdkv / arch)
# executable that is collecting & sending telemetry every time cl/link runs
(OUTPUT / "VC/Tools/MSVC" / msvcv / f"bin/Host{HOST}/{TARGET}/vctip.exe").unlink(missing_ok=True)


### setup.bat

SETUP_BAT = f"""@echo off

set ROOT=%~dp0

set MSVC_VERSION={msvcv}
set MSVC_HOST=Host{HOST}
set MSVC_ARCH={TARGET}
set SDK_VERSION={sdkv}
set SDK_ARCH={TARGET}
set VSCMD_ARG_TGT_ARCH={TARGET}

set MSVC_ROOT=%ROOT%VC\\Tools\\MSVC\\%MSVC_VERSION%
set SDK_INCLUDE=%ROOT%Windows Kits\\10\\Include\\%SDK_VERSION%
set SDK_LIBS=%ROOT%Windows Kits\\10\\Lib\\%SDK_VERSION%

set VCToolsInstallDir=%MSVC_ROOT%\\
set PATH=%MSVC_ROOT%\\bin\\%MSVC_HOST%\\%MSVC_ARCH%;%ROOT%Windows Kits\\10\\bin\\%SDK_VERSION%\\%SDK_ARCH%;%ROOT%Windows Kits\\10\\bin\\%SDK_VERSION%\\%SDK_ARCH%\\ucrt;%PATH%
set INCLUDE=%MSVC_ROOT%\\include;%SDK_INCLUDE%\\ucrt;%SDK_INCLUDE%\\shared;%SDK_INCLUDE%\\um;%SDK_INCLUDE%\\winrt;%SDK_INCLUDE%\\cppwinrt
set LIB=%MSVC_ROOT%\\lib\\%MSVC_ARCH%;%SDK_LIBS%\\ucrt\\%SDK_ARCH%;%SDK_LIBS%\\um\\%SDK_ARCH%

set WindowsSDKVersion=%SDK_VERSION%
set WindowsSdkDir=%ROOT%Windows Kits\\10\\
cmd
"""

(OUTPUT / "setup.bat").write_text(SETUP_BAT)

### setup.ps1

SETUP_PS1 = f"""$MSVC_VERSION = '{msvcv}'
$MSVC_HOST = 'Host{HOST}'
$MSVC_ARCH = '{TARGET}'
$SDK_VERSION = '{sdkv}'
$SDK_ARCH = '{TARGET}'
$env:VSCMD_ARG_TGT_ARCH = '{TARGET}'

$MSVC_ROOT = "${{PSScriptRoot}}\\VC\\Tools\\MSVC\\${{MSVC_VERSION}}"
$SDK_INCLUDE = "${{PSScriptRoot}}\\Windows Kits\\10\\Include\\${{SDK_VERSION}}"
$SDK_LIBS = "${{PSScriptRoot}}\\Windows Kits\\10\\Lib\\${{SDK_VERSION}}"

$env:VCToolsInstallDir = "${{MSVC_ROOT}}\\"
$env:PATH = "${{MSVC_ROOT}}\\bin\\${{MSVC_HOST}}\\${{MSVC_ARCH}};${{PSScriptRoot}}\\Windows Kits\\10\\bin\\${{SDK_VERSION}}\\${{SDK_ARCH}};${{PSScriptRoot}}\\Windows Kits\\10\\bin\\${{SDK_VERSION}}\\${{SDK_ARCH}}\\ucrt;${{env:PATH}}"
$env:INCLUDE = "${{MSVC_ROOT}}\\include;${{SDK_INCLUDE}}\\ucrt;${{SDK_INCLUDE}}\\shared;${{SDK_INCLUDE}}\\um;${{SDK_INCLUDE}}\\winrt;${{SDK_INCLUDE}}\\cppwinrt"
$env:LIB = "${{MSVC_ROOT}}\\lib\\${{MSVC_ARCH}};${{SDK_LIBS}}\\ucrt\\${{SDK_ARCH}};${{SDK_LIBS}}\\um\\${{SDK_ARCH}}"

$env:WindowsSDKVersion = "${{SDK_VERSION}}"
$env:WindowsSdkDir = "${{PSScriptRoot}}\\Windows Kits\\10\\"
"""

(OUTPUT / "setup.ps1").write_text(SETUP_PS1)

### setup.sh

SETUP_SH = f"""export MY_ROOT="$PWD"

export MSVC_VERSION={msvcv}
export MSVC_HOST=Host{HOST}
export MSVC_ARCH={TARGET}
export SDK_VERSION={sdkv}
export SDK_ARCH={TARGET}
export VSCMD_ARG_TGT_ARCH={TARGET}

export MSVC_ROOT="${{MY_ROOT}}/VC/Tools/MSVC/${{MSVC_VERSION}}"
export SDK_INCLUDE="${{MY_ROOT}}/Windows Kits/10/Include/${{SDK_VERSION}}"
export SDK_LIBS="${{MY_ROOT}}/Windows Kits/10/Lib/${{SDK_VERSION}}"

export VCToolsInstallDir="${{MSVC_ROOT}}/"
export PATH="${{MSVC_ROOT}}/bin/${{MSVC_HOST}}/${{MSVC_ARCH}};${{MY_ROOT}}/Windows Kits/10/bin/${{SDK_VERSION}}/${{SDK_ARCH}};${{MY_ROOT}}/Windows Kits/10/bin/${{SDK_VERSION}}/${{SDK_ARCH}}/ucrt;${{PATH}}"
export INCLUDE="${{MSVC_ROOT}}/include;${{SDK_INCLUDE}}/ucrt;${{SDK_INCLUDE}}/shared;${{SDK_INCLUDE}}/um;${{SDK_INCLUDE}}/winrt;${{SDK_INCLUDE}}/cppwinrt"
export LIB="${{MSVC_ROOT}}/lib/${{MSVC_ARCH}};${{SDK_LIBS}}/ucrt/${{SDK_ARCH}};${{SDK_LIBS}}/um/${{SDK_ARCH}}"

export WindowsSDKVersion="${{SDK_VERSION}}"
export WindowsSdkDir="${{MY_ROOT}}/Windows Kits/10/"
"""

(OUTPUT / "setup.sh").write_text(SETUP_SH)

print(f"Total downloaded: {total_download>>20} MB")
print("Done!")