From 39e7f60c5a5ba71a0605dedd676efcb15bb9770d Mon Sep 17 00:00:00 2001
From: Nick Bolton <nick@symless.com>
Date: Tue, 11 Mar 2025 16:48:39 +0000
Subject: [PATCH] build: Get minor MSVC version from host registry

---
 CMakeLists.txt                         | 18 ++++++++++++++++--
 src/lib/arch/win32/ArchMiscWindows.cpp | 17 ++---------------
 2 files changed, 18 insertions(+), 17 deletions(-)

diff --git a/CMakeLists.txt b/CMakeLists.txt
index fb2be894d..9acd2c10d 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -94,8 +94,22 @@ set(REQUIRED_OPENSSL_VERSION 3.0)
 set(REQUIRED_LIBEI_VERSION 1.3)
 set(REQUIRED_LIBPORTAL_VERSION 0.8)
 set(REQUIRED_QT_VERSION 6.7.0)
-set(REQUIRED_MSVC_RUNTIME_MAJOR 14)
-set(REQUIRED_MSVC_RUNTIME_MINOR 42)
+
+if (MSVC)
+  # On Windows, require that the same MSVC runtime is used as on the host.
+  # Mitigates things like access violations caused by accidental ABI-compatibility breakage.
+  set(REQUIRED_MSVC_RUNTIME_MAJOR 14)
+  cmake_host_system_information(
+    RESULT REQUIRED_MSVC_RUNTIME_MINOR
+    QUERY WINDOWS_REGISTRY
+    "HKLM/SOFTWARE/Microsoft/VisualStudio/${REQUIRED_MSVC_RUNTIME_MAJOR}.0/VC/Runtimes/x64"
+    VALUE "Minor")
+  if (REQUIRED_MSVC_RUNTIME_MINOR)
+    message(STATUS "MSVC runtime: ${REQUIRED_MSVC_RUNTIME_MAJOR}.${REQUIRED_MSVC_RUNTIME_MINOR}")
+  else()
+    message(FATAL_ERROR "MSVC runtime registry entry not found")
+  endif()
+endif()
 
 # Control debug item visibility
 # When not set logging is forced to DEBUG and show code locations
diff --git a/src/lib/arch/win32/ArchMiscWindows.cpp b/src/lib/arch/win32/ArchMiscWindows.cpp
index 33fd3ff77..80efd379a 100644
--- a/src/lib/arch/win32/ArchMiscWindows.cpp
+++ b/src/lib/arch/win32/ArchMiscWindows.cpp
@@ -17,19 +17,6 @@
 #include <array>
 #include <filesystem>
 
-// See table of the compiler versions and the matching runtime DLL versions:
-// https://dev.to/yumetodo/list-of-mscver-and-mscfullver-8nd
-#if _MSC_VER >= 1942 // Visual Studio 2022 Update 12 (v17.12.4)
-const auto kRequiredMajor = kWindowsRuntimeMajor;
-const auto kRequiredMinor = kWindowsRuntimeMinor;
-#elif _MSC_VER >= 1920 // Visual Studio 2019 Update 7 (v16.7)
-const auto kRequiredMajor = 14;
-const auto kRequiredMinor = 27;
-#else
-#pragma message("MSC version: " STRINGIFY(_MSC_VER))
-#error "Unsupported MSC version"
-#endif
-
 // Useful for debugging Windows specific bootstrapping code before the logging system is initialized.
 // This output can be viewed by attaching a Microsoft debugger or by using the DebugView program.
 #define MS_LOG_DEBUG(message, ...)                                                                                     \
@@ -606,12 +593,12 @@ void ArchMiscWindows::guardRuntimeVersion() // NOSONAR - `noreturn` is not avail
 
   MS_LOG_DEBUG("msvc runtime dll version: %d.%d.%d", currentMajor, currentMinor, currentBuild);
 
-  if (currentMajor < kRequiredMajor || currentMinor < kRequiredMinor) {
+  if (currentMajor < kWindowsRuntimeMajor || currentMinor < kWindowsRuntimeMinor) {
     const auto message = deskflow::string::sprintf(
         "Installed Microsoft Visual C++ Runtime v%d.%d.%d is outdated.\n\n"
         "Minimum required version: v%d.%d\n\n"
         "Please update to the latest Microsoft Visual C++ Redistributable.",
-        currentMajor, currentMinor, currentBuild, kRequiredMajor, kRequiredMinor
+        currentMajor, currentMinor, currentBuild, kWindowsRuntimeMajor, kWindowsRuntimeMinor
     );
     MessageBoxA(nullptr, message.c_str(), "Dependency Error", MB_ICONERROR | MB_OK);
     exit(1);