How to use _CRT_SECURE_NO_WARNINGS
C++Visual C++Visual Studio-2012WarningsC++ Problem Overview
I have compile error in my simple MFC window application generated from wizard with several lines of code:
> error C4996: 'strncpy': This function or variable may be unsafe. Consider using strncpy_s instead. To disable deprecation, use _CRT_SECURE_NO_WARNINGS. See online help for details.
I set Configuration Properties>>C/C++>>Preporocessor>>Preprocessor Definitions>> _CRT_NONSTDC_NO_WARNINGS
But this does't helped. I have another very close project that generates only warning in this place and it has no _CRT_NONSTDC_NO_WARNINGS
definition.
Only difference between projects is several different options in wizard.
Why _CRT_NONSTDC_NO_WARNINGS does not helps in first project and why second project compiles without problems without this definition?
C++ Solutions
Solution 1 - C++
Add by
> Configuration Properties>>C/C++>>Preporocessor>>Preprocessor > Definitions>> _CRT_SECURE_NO_WARNINGS
Solution 2 - C++
Under "Project -> Properties -> C/C++ -> Preprocessor -> Preprocessor Definitions" add _CRT_SECURE_NO_WARNINGS
Solution 3 - C++
If your are in Visual Studio 2012 or later this has an additional setting 'SDL checks' Under Property Pages -> C/C++ -> General
> Additional Security Development Lifecycle (SDL) recommended checks; includes enabling additional secure code generation features and extra security-relevant warnings as errors.
It defaults to YES - For a reason, I.E you should use the secure version of the strncpy. If you change this to NO you will not get a error when using the insecure version.
Solution 4 - C++
For a quick fix or test, I find it handy just adding #define _CRT_SECURE_NO_WARNINGS
to the top of the file before all #include
#define _CRT_SECURE_NO_WARNINGS
#include ...
int main(){
//...
}
Solution 5 - C++
Adding _CRT_SECURE_NO_WARNINGS
to Project -> Properties -> C/C++ -> Preprocessor -> Preprocessor Definitions didn't work for me, don't know why.
The following hint works: In stdafx.h file, please add
#define _CRT_SECURE_NO_DEPRECATE
before include other header files.
Solution 6 - C++
Visual Studio 2019 with CMake
Add the following to CMakeLists.txt
:
add_definitions(-D_CRT_SECURE_NO_WARNINGS)
Solution 7 - C++
I was getting the same error in Visual Studio 2017 and to fix it just added #define _CRT_SECURE_NO_WARNINGS
after #include "pch.h"
#include "pch.h"
#define _CRT_SECURE_NO_WARNINGS
....