cmake 项目。qt5升级 qt6 报错 error: “Qt requires a C++17 compiler 已解决

 

  

  日常项目开发中。需要对qt5升级到qt6 做cmake兼容配置，在编译中发现，有c++ 编译环境 报错

2>C:\Qt\6.5.3\msvc2019_64\include\QtCore/qcompilerdetection.h(1226,1): fatal error C1189: #error:  "Qt requires a C++17 compiler, and a suitable value for __cplusplus. On MSVC, you must pass the /Zc:__cplusplus option to the compiler."
2>CFrameworkMainWidget.cpp
2>C:\Qt\6.5.3\msvc2019_64\include\QtCore/qcompilerdetection.h(1226,1): fatal error C1189: #error:  "Qt requires a C++17 compiler, and a suitable value for __cplusplus. On MSVC, you must pass the /Zc:__cplusplus option to the compiler."
2>CSliderBar.cpp
2>C:\Qt\6.5.3\msvc2019_64\include\QtCore/qcompilerdetection.h(1226,1): fatal error C1189: #error:  "Qt requires a C++17 compiler, and a suitable value for __cplusplus. On MSVC, you must pass the /Zc:__cplusplus option to the compiler."

解决办法

# 设置msvc运行库 需设置在 project 之前
# https://cmake.org/cmake/help/latest/variable/CMAKE_MSVC_RUNTIME_LIBRARY.html
set(CMAKE_MSVC_RUNTIME_LIBRARY "MultiThreaded$<$<CONFIG:Debug>:Debug>DLL")# 设置c++标准为17 需设置在 project 之前
set(CMAKE_CXX_STANDARD 17)
set(CMAKE_CXX_STANDARD_REQUIRED ON)
set(CMAKE_CXX_EXTENSIONS OFF)# 增加编译选项
add_compile_options("/permissive-")
add_compile_options("/Zc:__cplusplus")