C++20 features are available since GCC 8.
To enable C++20 support, add the command-line parameter
-std=c++20
For G++ 9 and earlier use
-std=c++2a
Or, to enable GNU extensions in addition to C++20 features, add
-std=gnu++20
C++20 features are available since GCC 8.
To enable C++20 support, add the command-line parameter
-std=c++20
For G++ 9 and earlier use
-std=c++2a
Or, to enable GNU extensions in addition to C++20 features, add
-std=gnu++20