Blank output when compiled with GCC and ASM is enabled

[shssoichiro]

Initially brought this up in #13 (comment), thought it made sense to create an issue to track this, even if there's no clue on a solution. Several others have reproduced it, so I wanted to document the workaround as well.

The workaround is to build this plugin with Clang or MSVC. You can use clang by prefixing CC=clang CXX=clang++ to the meson build step.

[Stefan-Olt]

Any idea what causes this issue? I have created a build repo for Linux (and macOS) that uses gcc, supporting another compiler is quite difficult (it's a custom build compiler using an old libc6 for compatibility with many Linux distributions).
So I would rather fix the issue here. Additionally this could be an issue that may not be GCC specific and could occur with newer clang versions or optimization options as well

[Stefan-Olt]

Investigation:
I started replacing all SSE2 functions with their C equivalent, I had to replace all functions used to make it work correctly. This told me it is a general issue, not a single line.
And I found it auto&causes the problem, if I just use auto everything is fine. Can someone test if changing that does brake Clang/MSVC support?

[Stefan-Olt]

Have now open a pull request for a fix (also including Neon optimizations)