c++版本判断

c++ 版本

如何在代码中判断c++版本
使用 __cplusplus

#include  
#include  
using namespace std;
int main(int argc, char** argv)
{
    cout << __GNUC__ << endl;
    cout << __cplusplus << endl;
    return 0;
}

结果如下:

$g++ test.cpp  -o test && ./test
4
199711

$g++ test.cpp  --std=c++14 -o test && ./test 
4
201300

$g++ test.cpp  --std=c++11 -o test && ./test  
4
201103

$g++ test.cpp  --std=c++17 -o test && ./test  
g++: error: unrecognized command line option '--std=c++17'

$g++ --version
g++ (GCC) 4.9.2
Copyright (C) 2014 Free Software Foundation, Inc.
This is free software; see the source for copying conditions.  There is NO
warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.

---

Ref:

• https://stackoverflow.com/questions/38456127/what-is-the-value-of-cplusplus-for-c17