Compile using cpp backend

[jerous86]

I want to use pixie in a nim program that can only be compiled with the cpp backend.
However, pixie cannot be compiled using this cpp backend on my system (mac OS 12).

For example,
nim cpp --gc:orc -d:release -r tests/all.nim
results in multiple errors like

.cache/nim/all_r/@m..@ssrc@spixie@[email protected]:197:5: error: no matching function for call to '_mm256_store_si256'
                                _mm256_store_si256(((void*) (p)), colorVec);
                                ^~~~~~~~~~~~~~~~~~
/Library/Developer/CommandLineTools/usr/lib/clang/12.0.0/include/avxintrin.h:3277:1: note: candidate function not viable: cannot convert argument of incomplete type
      'void *' to '__m256i *' for 1st argument
_mm256_store_si256(__m256i *__p, __m256i __a)

Anyway to get it compiling using nim cpp?

[iffy]

Try nim cpp -d:pixieNoSimd -d:zippyNoSimd -r tests/all.nim

[amaank404]

Why wouldn't SIMD instructions work on C++? Just Curious

[guzba]

We run all of our tests using nim cpp for every commit so I can be confident C++ is not the issue here. The real question is why does it not work on your computer which is unfortunately much harder to answer from far away.

[guzba]

Yeah this is something Mac specific.

[guzba]

It appears clang on Mac requires pointers to be cast to something like const __m128i_u *. This is a made-up requirement, serves no purpose and is dumb. Fortunately no other compilers require it so I'm not eager to do anything here.