>>x1f604+(OP)
I did a double take on this because I wrote a blog post about this topic a few months ago and came to a very different conclusion, that the results are effectively identical on clang and gcc is just weird.
Then I realized that I was writing about compiling for ARM and this post is about x86. Which is extra weird! Why is the compiler better tuned for ARM than x86 in this case?
Never did figure out what gcc's problem was.
https://godbolt.org/z/Y75qnTGdr