Issue with rv64

[FantasqueX]

Hi, I noticed that #350 adds an exception for rv64 which solves the same issue with #370. I should apologize here because I didn't notice that PR when I created my PR. I think one PR should be reverted, two snippets of code which try to solve the same problem is bad.

[9600]

And a new issue raised? This is getting confusing :o) OK, hopefully @rjonaitis can resolve in the best way possible.

[FantasqueX]

I haven't noticed any new issue. It's just confusing

[9600]

I meant opening this new issue, instead of commenting on #370.

[FantasqueX]

It's a mistake actually. I should comment next time.

[rjonaitis]

#370 can stay as a protective measure against -march=native usage where it is not supported, although I tried to check the check_cxx_compiler_flag() even with faulty parameters, it did not report any issues with them, so results might vary depeding on compiler.
#350 can also stay, but kind of needs modification, it currently just defines set(DEFAULT_SIMD_FLAGS "rv64"), but this flag is not matched in CMakeLists.txt#L139-L157 so essentially it just avoids the '-march=native' case, but does not actually add definition to compile with -march=rv64

I don't have RISC-V board or cross compile tools setup right now, so can't actually verify what the compiler is doing then.

[FantasqueX]

#370 can stay as a protective measure against -march=native usage where it is not supported, although I tried to check the check_cxx_compiler_flag() even with faulty parameters, it did not report any issues with them, so results might vary depeding on compiler.

What faulty parameters did you try? I think it may relate to an issue with CMake. However, it works well -march=native.

#350 can also stay, but kind of needs modification, it currently just defines set(DEFAULT_SIMD_FLAGS "rv64"), but this flag is not matched in CMakeLists.txt#L139-L157 so essentially it just avoids the '-march=native' case, but does not actually add definition to compile with -march=rv64

I think those changes can be reverted. We (ArchLinux RISC-V) add compile flags -march=rv64gc when packaging. And gcc has a default march value when there is no explicit march argument. I'm quite sure LimeSuite can be built well when there is no match case.