[$] Compiling to BPF with GCC

The addition of extended BPF to the kernel has opened up a whole range ofuse cases, but few developers actually write BPF code. It is, like anyother assembly-level language, a tedious pain to work with; developerswould rather use a higher-level language. For BPF, the language of choiceis C, which is compiled to BPF with the LLVM compiler. But, as JoseMarchesi described during the Toolchainsmicroconference at the 2019 LinuxPlumbers Conference, LLVM will soon have company, as he has just addedsupport for a BPF back-end to the GCC compiler.