From f62f43c0dae041b1a7dd282d3f1c055fa7038649 Mon Sep 17 00:00:00 2001
From: Morph <39850852+Morph1984@users.noreply.github.com>
Date: Tue, 6 Jun 2023 20:19:44 -0400
Subject: [PATCH] CMakeLists: Force C++20 on MSVC due to conflicts with C++23
modules
The latest version of MSVC STL brings C++23 standard library modules, which conflict with precompiled headers.
Disabling with /experimental:module- has no effect, so force C++20 in the meantime while we wait for module support in other compilers.
---
CMakeLists.txt | 2 +-
src/CMakeLists.txt | 6 ++++--
2 files changed, 5 insertions(+), 3 deletions(-)
diff --git a/CMakeLists.txt b/CMakeLists.txt
index 30a3c939e..3d03bbf94 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -255,7 +255,7 @@ endif()
# boost asio's concept usage doesn't play nicely with some compilers yet.
add_definitions(-DBOOST_ASIO_DISABLE_CONCEPTS)
if (MSVC)
- add_compile_options($<$<COMPILE_LANGUAGE:CXX>:/std:c++latest>)
+ add_compile_options($<$<COMPILE_LANGUAGE:CXX>:/std:c++20>)
# boost still makes use of deprecated result_of.
add_definitions(-D_HAS_DEPRECATED_RESULT_OF)
diff --git a/src/CMakeLists.txt b/src/CMakeLists.txt
index 55b113297..0696201df 100644
--- a/src/CMakeLists.txt
+++ b/src/CMakeLists.txt
@@ -43,7 +43,7 @@ if (MSVC)
/Zo
/permissive-
/EHsc
- /std:c++latest
+ /std:c++20
/utf-8
/volatile:iso
/Zc:externConstexpr
@@ -51,8 +51,10 @@ if (MSVC)
/Zc:throwingNew
/GT
+ # Modules
+ /experimental:module- # Disable module support explicitly due to conflicts with precompiled headers
+
# External headers diagnostics
- /experimental:external # Enables the external headers options. This option isn't required in Visual Studio 2019 version 16.10 and later
/external:anglebrackets # Treats all headers included by #include <header>, where the header file is enclosed in angle brackets (< >), as external headers
/external:W0 # Sets the default warning level to 0 for external headers, effectively turning off warnings for external headers