added [[noreturn]] attribute to pybind11_fail

Author: wjakob

example/example12.cpp

@@ -56,7 +56,6 @@ class PyExample12 : public Example12 {
                           /* This function has no arguments. The trailing comma
                              in the previous line is needed for some compilers */
         );
-        throw std::runtime_error("this will never be reached");
     }
 
     virtual void pure_virtual() {

include/pybind11/common.h

@@ -324,7 +324,7 @@ struct error_already_set : public std::runtime_error { public: error_already_set
 /// Thrown when pybind11::cast or handle::call fail due to a type casting error
 struct cast_error        : public std::runtime_error { public: cast_error(const std::string &w = "") : std::runtime_error(w)     {} };
 
-PYBIND11_NOINLINE inline void pybind11_fail(const char *reason) { throw std::runtime_error(reason); }
-PYBIND11_NOINLINE inline void pybind11_fail(const std::string &reason) { throw std::runtime_error(reason); }
+[[noreturn]] PYBIND11_NOINLINE inline void pybind11_fail(const char *reason) { throw std::runtime_error(reason); }
+[[noreturn]] PYBIND11_NOINLINE inline void pybind11_fail(const std::string &reason) { throw std::runtime_error(reason); }
 
 NAMESPACE_END(pybind11)