I know how intrinsic work, thanks. Use them a lot in C++. C99 language spec says nothing about the things you’re talking about. It only specifies the language,

I know how intrinsic work, thanks. Use them a lot in C++. C99 language spec says nothing about the things you’re talking about. It only specifies the language, not how C compilers implement various features. From the programmer’s point of view (except when the programmer works on the compiler itself), intrinsics are just C library functions, only inline, and very performant if done right. Fully compliant with C99 and C++ language specs.