Why would you need to? Build your binary, test it, give it to your customers. Why do you have to test every compiler?
For example your carefully written C++ code with gcc, might crash and burn with the TI compiler that is the only way to target a specific SOC.
Or maybe that other customer doing HPC only accepts your code if compiled with Intel or IBM compilers.
Then you build it, test it and deploy it. No clue what you are on about.
Check Boost's codebase as an example of such portability efforts.
Why would you need to? Build your binary, test it, give it to your customers. Why do you have to test every compiler?