Did you check out the clang vector extensions? And before "but that's not standard C!": in the C world, the interesting stuff happens outside the standard in language extensions, the standard is mostly irrelevant for real world code. What counts is what specific compilers have to offer.
To the point that Linux, probably the most important C project in the world, was written in the GCC dialect for many many years. I think it's no longer the case.
AFAIK the only reason why Linux compiles on Clang now too is because Clang tries to emulate GCC behaviour as closely as possible? I doubt that the Linux kernel would compile out of the box with Microsoft's C compiler for instance ;)
How is it special at all?
> you have full control on low level details.
Yeah, if you add random attributes to the language and control the compiler. C still can’t properly do vector instructions, while even Java can, but so can C#, Rust, C++. It’s simply not a low-level language.