SDL: cmake: remove /RTC1 from CXX flags when building with SDL_LIBC=OFF

SDL Commits
1 
From cfb8e591cb99068a39f834900863610ba3780553 Mon Sep 17 00:00:00 2001
From: Anonymous Maarten <[EMAIL REDACTED]>
Date: Thu, 10 Jul 2025 22:52:56 +0200
Subject: [PATCH] cmake: remove /RTC1 from CXX flags when building with
 SDL_LIBC=OFF

---
 CMakeLists.txt | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/CMakeLists.txt b/CMakeLists.txt
index 8898be36a2d2f..b891873c655aa 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -189,9 +189,12 @@ if(MSVC)
     # Make sure /RTC1 is disabled, otherwise it will use functions from the CRT
     foreach(flag_var
         CMAKE_C_FLAGS CMAKE_C_FLAGS_DEBUG CMAKE_C_FLAGS_RELEASE
-        CMAKE_C_FLAGS_MINSIZEREL CMAKE_C_FLAGS_RELWITHDEBINFO)
+        CMAKE_C_FLAGS_MINSIZEREL CMAKE_C_FLAGS_RELWITHDEBINFO
+        CMAKE_CXX_FLAGS CMAKE_CXX_FLAGS_DEBUG CMAKE_CXX_FLAGS_RELEASE
+        CMAKE_CXX_FLAGS_MINSIZEREL CMAKE_CXX_FLAGS_RELWITHDEBINFO)
       string(REGEX REPLACE "/RTC(su|[1su])" "" ${flag_var} "${${flag_var}}")
     endforeach(flag_var)
+    set(CMAKE_MSVC_RUNTIME_CHECKS "")
   endif()
 
   if(MSVC_CLANG)