From 3ce596a9567ac3944a783f24903af3ad6bbe1ba1 Mon Sep 17 00:00:00 2001
From: Viktor Szakats <commit@vsz.me>
Date: Thu, 12 Feb 2026 17:59:18 +0100
Subject: [PATCH] msvc: VS2026: unlock picky warning in cmake, test in CI

Upgrade a GHA/windows job to VS2026 (from VS2022), using a runner image
released a week ago. It also comes with the same Windows SDK as VS2022:
v10.0.26100.0.

The runner image uses Windows 2025 unfortunately, which makes the job
run significantly slower than before this patch:
- configure: 49s -> 1m10s
- build: 3s -> 5s
- install test prereqs: 23s -> 27s
- run tests: 3m18s -> 4m11s
- build examples: 15s -> 25s

It's a shame.

Also:
- cmake: enable picky warnings for VS2026 internal version 19.50.
  Build is clean with existing options.
- GHA/windows: make the built-in OpenSSH intall path recognize
  the windows-2025-vs2026 image as windows-2025.
- windows-2025-vs2026 is able to load the cached stunnel made on
  the windows-2022 runner.
- disk use of the build is almost identical to VS2022.

Before: https://github.com/curl/curl/actions/runs/21955482367/job/63418133880
After: https://github.com/curl/curl/actions/runs/21957589847/job/63426546943

Ref: https://github.com/actions/runner-images/blob/71f0157880be328a2b0a4dc81cda61735ba6c45d/images/windows/Windows2025-VS2026-Readme.md
Ref: #20575

Closes #20577
---
 .github/workflows/windows.yml | 9 +++++++--
 CMake/PickyWarnings.cmake     | 2 +-
 2 files changed, 8 insertions(+), 3 deletions(-)

diff --git a/.github/workflows/windows.yml b/.github/workflows/windows.yml
index de6bc75575..eecc91eca1 100644
--- a/.github/workflows/windows.yml
+++ b/.github/workflows/windows.yml
@@ -808,6 +808,7 @@ jobs:
             env: 'ucrt-x86_64'
             plat: 'windows'
             type: 'Debug'
+            image: 'windows-2025-vs2026'
             chkprefill: '_chkprefill'
             config: >-
               -DENABLE_DEBUG=ON
@@ -910,9 +911,11 @@ jobs:
               # Officially this requires the vcvarsall.bat MS-DOS batch file (as of
               # VS2022). Since it integrates badly with CI steps and shell scripts,
               # reproduce the necessary build configuration manually, without envs.
+              MSVC_EDITION='2022/Enterprise/vc/tools/msvc'
+              [[ "${MATRIX_IMAGE}" = *'vs2026'* ]] && MSVC_EDITION='18/Enterprise/vc/tools/msvc'
               [[ "$(uname -s)" = *'ARM64'* ]] && MSVC_HOST='arm64' || MSVC_HOST='x64'  # x86
               MSVC_ROOTD="$(cygpath --mixed --short-name "$PROGRAMFILES/Microsoft Visual Studio")"  # to avoid spaces in directory names
-              MSVC_ROOTU="$(/usr/bin/find "$(cygpath --unix "$MSVC_ROOTD/2022/Enterprise/vc/tools/msvc")" -mindepth 1 -maxdepth 1 -type d -name '*.*' | sort | tail -n 1)"
+              MSVC_ROOTU="$(/usr/bin/find "$(cygpath --unix "$MSVC_ROOTD/$MSVC_EDITION")" -mindepth 1 -maxdepth 1 -type d -name '*.*' | sort | tail -n 1)"
               MSVC_ROOTW="$(cygpath --mixed "$MSVC_ROOTU")"
               MSVC_ROOTU="$(cygpath --unix "$MSVC_ROOTW")"
               MSVC_BINU="$MSVC_ROOTU/bin/Host$MSVC_HOST/$MATRIX_ARCH"
@@ -938,6 +941,8 @@ jobs:
               options+=" -DCMAKE_MT=$MSDK_BINU/mt.exe"
               options+=" -DCMAKE_C_COMPILER=$MSVC_BINU/cl.exe"
               export CMAKE_GENERATOR='Ninja Multi-Config'  # pass it via env to avoid space issues
+              echo "Using MSVC: ${MSVC_ROOTW}"
+              echo "Using Windows SDK: ${MSDK_VER}"
             fi
             [ "${_chkprefill}" = '_chkprefill' ] && options+=' -D_CURL_PREFILL=OFF'
             if [ -n "${MATRIX_INSTALL_VCPKG}" ]; then
@@ -1009,7 +1014,7 @@ jobs:
             /usr/bin/pacman --noconfirm --noprogressbar --sync --needed openssh
           elif [ "${MATRIX_OPENSSH}" = 'OpenSSH-Windows-builtin' ]; then
             # https://learn.microsoft.com/windows-server/administration/openssh/openssh_install_firstuse
-            if [ "${MATRIX_IMAGE}" != 'windows-2025' ]; then
+            if [[ "${MATRIX_IMAGE}" = *'windows-2025'* ]]; then
               pwsh -Command 'Add-WindowsCapability -Online -Name OpenSSH.Client~~~~0.0.1.0'
               pwsh -Command 'Add-WindowsCapability -Online -Name OpenSSH.Server~~~~0.0.1.0'
             fi
diff --git a/CMake/PickyWarnings.cmake b/CMake/PickyWarnings.cmake
index 980e017f30..fff4deddc9 100644
--- a/CMake/PickyWarnings.cmake
+++ b/CMake/PickyWarnings.cmake
@@ -395,7 +395,7 @@ if(PICKY_COMPILER)
         list(APPEND _picky "-Wno-conversion")  # Avoid false positives
       endif()
     endif()
-  elseif(MSVC AND MSVC_VERSION LESS_EQUAL 1944)  # Skip for untested/unreleased newer versions
+  elseif(MSVC AND MSVC_VERSION LESS_EQUAL 1950)  # Skip for untested/unreleased newer versions
     list(APPEND _picky "-Wall")
     list(APPEND _picky "-wd4061")  # enumerator 'A' in switch of enum 'B' is not explicitly handled by a case label
     list(APPEND _picky "-wd4191")  # 'type cast': unsafe conversion from 'FARPROC' to 'void (__cdecl *)(void)'