So very recently Intel seems to be making ALL of their compiler FREE.
I reference these too links:
https://community.intel.com/t5/Intel-Fortran-Compiler/Webinar-Nov-11th-9am-PST-oneAPI-Compilers-discussed/td-p/1227214
and
https://fortran-lang.discourse.group/t/intel-releases-oneapi-toolkit-free-fortran-2018/471
Now the last link is FORTRAN I know but Steve Lionel is a FORTRAN legend having worked for DEC/COMPAQ/HP/Intel following the course of the compiler.
The webinar talks as much or more about C/C++ as it does anything else so it is a good fit. This release should be for Linux & Windows.
On a personal note having used a bunch o' compilers in 40 yrs Intel's have been VERY good.
I open the floor for discussion, (Grin)