title: how to use llvm+clang to compile for stm32
body: <p>Has someone infos how to build a llvm+clang toolchain using binutils and newlib and how to use it?</p>
  
  <ul>
  <li>host: Linux, AMD64</li>
  <li>target: cortex-m3, stm32</li>
  <li>c-lib: newlib </li>
  <li>assembler: gnu as</li>
  </ul>