Build options for C++ projects

I am building a custom C++ package using cmake no Jetson Nano.
I want to know what values should be set for the following variables;

-mfpu
-march

What purpose for these flag?
I didn’t set any of them at all.

I think mfpu is from 32-bit builds to set which FPU type an older ARMv7 is using (e.g., hardware floating point is armhf). I have not checked, but I doubt it exists for ARMv8-a since all of the ARMv8 32-bit compatibility must have hardware floating point…basically it was an option in the past, but no longer is.

The march might have optimizations for different subsets of the ARMv8-a architecture, e.g., ARMv8.1-a versus ARMv8.2-a. Not sure what applies to the different Jetsons.

@ShaneCCC I am not quite sure about the flags. But I was able to build the code successfully by removing these from Cmakelists.

@linuxdev That clarifies their use. Thanks a lot!