Add [[noreturn]] to 1 file inc gloo/transport/tcp/pair.cc

Summary: LLVM-15 has a warning `-Wno-return` which can be used to identify functions that do not return. Qualifying these functions with `[[noreturn]]` is a perf optimization.

Reviewed By: meyering

Differential Revision: D53815466

fbshipit-source-id: 02f0b2e4d33ff118c55d285a4e623574c13e378f

Author: r-barnes

gloo/transport/tcp/pair.cc

@@ -1080,11 +1080,11 @@ void Pair::signalException(std::exception_ptr ex) {
   changeState(CLOSED);
 }
 
-void Pair::signalAndThrowException(const std::string& msg) {
+[[noreturn]] void Pair::signalAndThrowException(const std::string& msg) {
   signalAndThrowException(std::make_exception_ptr(::gloo::IoException(msg)));
 }
 
-void Pair::signalAndThrowException(std::exception_ptr ex) {
+[[noreturn]] void Pair::signalAndThrowException(std::exception_ptr ex) {
   signalException(ex);
   std::rethrow_exception(ex);
 }

gloo/transport/tcp/pair.h

@@ -325,8 +325,8 @@ class Pair : public ::gloo::transport::Pair, public Handler {
   void signalException(std::exception_ptr);
 
   // Like signalException, but throws exception as well.
-  void signalAndThrowException(const std::string& msg);
-  void signalAndThrowException(std::exception_ptr ex);
+  [[noreturn]] void signalAndThrowException(const std::string& msg);
+  [[noreturn]] void signalAndThrowException(std::exception_ptr ex);
 
   // Cache exception such that it can be rethrown if any function on
   // this instance is called again when it is in an error state.