[libcxx-commits] [libcxx] [libc++][NFC] Use [[deprecated]] for __grow_by (PR #209126)

[Nikolas Klauser via libcxx-commits]

https://github.com/philnik777 created https://github.com/llvm/llvm-project/pull/209126

`__grow_by` is an internal function, and we deprecated it to avoid accidental use of it inside the library. `_LIBCPP_DEPRECATED_` is meant for user-configuration, which doesn't apply here.

Fixes #124940


>From fd74a816f4c012ad5ebd066c025e3e614356a778 Mon Sep 17 00:00:00 2001
From: Nikolas Klauser <nikolasklauser at berlin.de>
Date: Mon, 13 Jul 2026 11:53:06 +0200
Subject: [PATCH] [libc++][NFC] Use [[deprecated]] for __grow_by

---
 libcxx/include/string | 17 ++++++++---------
 1 file changed, 8 insertions(+), 9 deletions(-)

diff --git a/libcxx/include/string b/libcxx/include/string
index a297a05813cee..39de836dbcf85 100644
--- a/libcxx/include/string
+++ b/libcxx/include/string
@@ -2343,17 +2343,16 @@ private:
   _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 void
   __init_with_size(_InputIterator __first, _Sentinel __last, size_type __sz);
 
-  _LIBCPP_CONSTEXPR_SINCE_CXX20
+  [[__deprecated__("use __grow_by_without_replace")]] _LIBCPP_CONSTEXPR_SINCE_CXX20
 #  if _LIBCPP_ABI_VERSION >= 2 //  We want to use the function in the dylib in ABIv1
   _LIBCPP_HIDE_FROM_ABI
 #  endif
-  _LIBCPP_DEPRECATED_("use __grow_by_without_replace") void __grow_by(
-      size_type __old_cap,
-      size_type __delta_cap,
-      size_type __old_sz,
-      size_type __n_copy,
-      size_type __n_del,
-      size_type __n_add = 0);
+  void __grow_by(size_type __old_cap,
+                 size_type __delta_cap,
+                 size_type __old_sz,
+                 size_type __n_copy,
+                 size_type __n_del,
+                 size_type __n_add = 0);
   _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI void __grow_by_without_replace(
       size_type __old_cap,
       size_type __delta_cap,
@@ -2682,7 +2681,7 @@ void _LIBCPP_CONSTEXPR_SINCE_CXX20
 #  if _LIBCPP_ABI_VERSION >= 2 // We want to use the function in the dylib in ABIv1
 _LIBCPP_HIDE_FROM_ABI
 #  endif
-_LIBCPP_DEPRECATED_("use __grow_by_without_replace") basic_string<_CharT, _Traits, _Allocator>::__grow_by(
+basic_string<_CharT, _Traits, _Allocator>::__grow_by(
     size_type __old_cap,
     size_type __delta_cap,
     size_type __old_sz,