Lots of changes for Intel/AMD/ARM/MIPS/PowerPC, eg AMD Rhyzen support. And new PDB tool. Clang has new diagnostic/”lint” abilities. The static analyzer uses Microsoft’s Z3 solver. New C and C++ features (wow, C++ is at C++17 already!). Many other changes! I wish I had time to look at it more detail today… 😦
http://releases.llvm.org/5.0.0/docs/ReleaseNotes.html
http://releases.llvm.org/5.0.0/tools/clang/docs/ReleaseNotes.html
http://releases.llvm.org/5.0.0/tools/clang/tools/extra/docs/ReleaseNotes.html
http://lists.llvm.org/pipermail/llvm-announce/2017-September/000075.html