[libcxx][NFC] Use macros for functions that support overriding detection (#133876)

We plan to replace the existing mechanism for overriding detection with
one that doesn't require the use of a special section as an alternative
to llvm/llvm-project#120805 which had other downsides.

This change is a pure refactoring that lays the foundation for a
subsequent change that will introduce the new detection mechanism.

GitOrigin-RevId: 25a03c1c7cec62ad7b6ed7a176df4e91ba968332
diff --git a/src/stdlib_new_delete.cpp b/src/stdlib_new_delete.cpp
index f386b28..b5ed599 100644
--- a/src/stdlib_new_delete.cpp
+++ b/src/stdlib_new_delete.cpp
@@ -63,7 +63,7 @@
   return p;
 }
 
-_LIBCPP_MAKE_OVERRIDABLE_FUNCTION_DETECTABLE _LIBCPP_WEAK void* operator new(std::size_t size) _THROW_BAD_ALLOC {
+_LIBCPP_OVERRIDABLE_FUNCTION(void*, operator new, (std::size_t size)) _THROW_BAD_ALLOC {
   void* p = operator_new_impl(size);
   if (p == nullptr)
     __throw_bad_alloc_shim();
@@ -74,7 +74,7 @@
 #if !_LIBCPP_HAS_EXCEPTIONS
 #  if _LIBCPP_CAN_DETECT_OVERRIDDEN_FUNCTION
   _LIBCPP_ASSERT_SHIM(
-      !std::__is_function_overridden(static_cast<void* (*)(std::size_t)>(&operator new)),
+      (!std::__is_function_overridden < void*(std::size_t), &operator new>()),
       "libc++ was configured with exceptions disabled and `operator new(size_t)` has been overridden, "
       "but `operator new(size_t, nothrow_t)` has not been overridden. This is problematic because "
       "`operator new(size_t, nothrow_t)` must call `operator new(size_t)`, which will terminate in case "
@@ -94,15 +94,13 @@
 #endif
 }
 
-_LIBCPP_MAKE_OVERRIDABLE_FUNCTION_DETECTABLE _LIBCPP_WEAK void* operator new[](size_t size) _THROW_BAD_ALLOC {
-  return ::operator new(size);
-}
+_LIBCPP_OVERRIDABLE_FUNCTION(void*, operator new[], (size_t size)) _THROW_BAD_ALLOC { return ::operator new(size); }
 
 _LIBCPP_WEAK void* operator new[](size_t size, const std::nothrow_t&) noexcept {
 #if !_LIBCPP_HAS_EXCEPTIONS
 #  if _LIBCPP_CAN_DETECT_OVERRIDDEN_FUNCTION
   _LIBCPP_ASSERT_SHIM(
-      !std::__is_function_overridden(static_cast<void* (*)(std::size_t)>(&operator new[])),
+      (!std::__is_function_overridden < void*(std::size_t), &operator new[]>()),
       "libc++ was configured with exceptions disabled and `operator new[](size_t)` has been overridden, "
       "but `operator new[](size_t, nothrow_t)` has not been overridden. This is problematic because "
       "`operator new[](size_t, nothrow_t)` must call `operator new[](size_t)`, which will terminate in case "
@@ -156,8 +154,7 @@
   return p;
 }
 
-_LIBCPP_MAKE_OVERRIDABLE_FUNCTION_DETECTABLE _LIBCPP_WEAK void*
-operator new(std::size_t size, std::align_val_t alignment) _THROW_BAD_ALLOC {
+_LIBCPP_OVERRIDABLE_FUNCTION(void*, operator new, (std::size_t size, std::align_val_t alignment)) _THROW_BAD_ALLOC {
   void* p = operator_new_aligned_impl(size, alignment);
   if (p == nullptr)
     __throw_bad_alloc_shim();
@@ -168,7 +165,7 @@
 #  if !_LIBCPP_HAS_EXCEPTIONS
 #    if _LIBCPP_CAN_DETECT_OVERRIDDEN_FUNCTION
   _LIBCPP_ASSERT_SHIM(
-      !std::__is_function_overridden(static_cast<void* (*)(std::size_t, std::align_val_t)>(&operator new)),
+      (!std::__is_function_overridden < void*(std::size_t, std::align_val_t), &operator new>()),
       "libc++ was configured with exceptions disabled and `operator new(size_t, align_val_t)` has been overridden, "
       "but `operator new(size_t, align_val_t, nothrow_t)` has not been overridden. This is problematic because "
       "`operator new(size_t, align_val_t, nothrow_t)` must call `operator new(size_t, align_val_t)`, which will "
@@ -188,8 +185,7 @@
 #  endif
 }
 
-_LIBCPP_MAKE_OVERRIDABLE_FUNCTION_DETECTABLE _LIBCPP_WEAK void*
-operator new[](size_t size, std::align_val_t alignment) _THROW_BAD_ALLOC {
+_LIBCPP_OVERRIDABLE_FUNCTION(void*, operator new[], (size_t size, std::align_val_t alignment)) _THROW_BAD_ALLOC {
   return ::operator new(size, alignment);
 }
 
@@ -197,14 +193,13 @@
 #  if !_LIBCPP_HAS_EXCEPTIONS
 #    if _LIBCPP_CAN_DETECT_OVERRIDDEN_FUNCTION
   _LIBCPP_ASSERT_SHIM(
-      !std::__is_function_overridden(static_cast<void* (*)(std::size_t, std::align_val_t)>(&operator new[])),
+      (!std::__is_function_overridden < void*(std::size_t, std::align_val_t), &operator new[]>()),
       "libc++ was configured with exceptions disabled and `operator new[](size_t, align_val_t)` has been overridden, "
       "but `operator new[](size_t, align_val_t, nothrow_t)` has not been overridden. This is problematic because "
       "`operator new[](size_t, align_val_t, nothrow_t)` must call `operator new[](size_t, align_val_t)`, which will "
       "terminate in case it fails to allocate, making it impossible for `operator new[](size_t, align_val_t, "
       "nothrow_t)` to fulfill its contract (since it should return nullptr upon failure). Please make sure you "
-      "override "
-      "`operator new[](size_t, align_val_t, nothrow_t)` as well.");
+      "override `operator new[](size_t, align_val_t, nothrow_t)` as well.");
 #    endif
 
   return operator_new_aligned_impl(size, alignment);