Improve attribute parsing & tests.
 - Support noreturn on function-typed variables.

 - Extend isFunctionOrMethod to return true for K&R functions and
   provide hasFunctionProto to check if a decl has information about
   its arguments. This code needs some serious cleaning, but works.

 - Add/improve test cases for noreturn and unused.


git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@57778 91177308-0d34-0410-b5e6-96231b3b80d8
4 files changed