[libc++abi][NFCI] Consistently group new_handler, unexpected_handler …

…and terminate_handler

Previously, the definitions of __cxa_terminate_handler and __cxa_unexpected_handler
(and their set_xxx_handler functions) were grouped together, but the
definition of __cxa_new_handler wasn't. This commit simply moves those
to the same file to treat all handlers consistently.

libcxxabi/src/cxa_default_handlers.cpp

@@ -5,7 +5,8 @@
 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
 //
 //
-// This file implements the default terminate_handler and unexpected_handler.
+// This file implements the default terminate_handler, unexpected_handler and
+// new_handler.
 //===----------------------------------------------------------------------===//
 
 #include <exception>
@@ -104,6 +105,8 @@ _LIBCPP_SAFE_STATIC std::terminate_handler __cxa_terminate_handler = default_ter
 _LIBCXXABI_DATA_VIS
 _LIBCPP_SAFE_STATIC std::unexpected_handler __cxa_unexpected_handler = default_unexpected_handler;
 
+std::new_handler __cxa_new_handler = 0;
+
 namespace std
 {
 
@@ -125,4 +128,10 @@ set_terminate(terminate_handler func) noexcept
                                     _AO_Acq_Rel);
 }
 
+new_handler
+set_new_handler(new_handler handler) noexcept
+{
+    return __libcpp_atomic_exchange(&__cxa_new_handler, handler, _AO_Acq_Rel);
+}
+
 }

libcxxabi/src/cxa_handlers.cpp

@@ -6,7 +6,7 @@
 //
 //
 // This file implements the functionality associated with the terminate_handler,
-//   unexpected_handler, and new_handler.
+// unexpected_handler, and new_handler.
 //===----------------------------------------------------------------------===//
 
 #include <stdexcept>
@@ -92,16 +92,6 @@ terminate() noexcept
     __terminate(get_terminate());
 }
 
-extern "C" {
-new_handler __cxa_new_handler = 0;
-}
-
-new_handler
-set_new_handler(new_handler handler) noexcept
-{
-    return __libcpp_atomic_exchange(&__cxa_new_handler, handler, _AO_Acq_Rel);
-}
-
 new_handler
 get_new_handler() noexcept
 {