[llvm-branch-commits] [libcxx] Prepare libcxx and libcxxabi for pointer field protection. (PR #151651)

[Peter Collingbourne via llvm-branch-commits]

https://github.com/pcc updated https://github.com/llvm/llvm-project/pull/151651

>From 7820ec4faa7ecb99217569794db9328211a61553 Mon Sep 17 00:00:00 2001
From: Peter Collingbourne <pcc at google.com>
Date: Fri, 10 Oct 2025 16:11:52 -0700
Subject: [PATCH] Address review comments

Created using spr 1.3.6-beta.1
---
 libcxx/CMakeLists.txt   |  6 +++++-
 libcxx/include/__config | 15 +--------------
 2 files changed, 6 insertions(+), 15 deletions(-)

diff --git a/libcxx/CMakeLists.txt b/libcxx/CMakeLists.txt
index a119850cd808e..3a87029b52980 100644
--- a/libcxx/CMakeLists.txt
+++ b/libcxx/CMakeLists.txt
@@ -201,7 +201,11 @@ set(LIBCXX_LIBRARY_VERSION "${LIBCXX_ABI_VERSION}.0" CACHE STRING
    For example, -DLIBCXX_LIBRARY_VERSION=x.y will result in the library being named
    libc++.x.y.dylib, along with the usual symlinks pointing to that. On Apple platforms,
    this also controls the linker's 'current_version' property.")
-set(LIBCXX_ABI_NAMESPACE "__${LIBCXX_ABI_VERSION}" CACHE STRING "The inline ABI namespace used by libc++. It defaults to __n where `n` is the current ABI version.")
+set(default_abi_namespace "__${LIBCXX_ABI_VERSION}")
+if(NOT LIBCXX_PFP STREQUAL "none")
+  set(default_abi_namespace "${default_abi_namespace}_pfp_${LIBCXX_PFP}")
+endif()
+set(LIBCXX_ABI_NAMESPACE "${default_abi_namespace}" CACHE STRING "The inline ABI namespace used by libc++. It defaults to __n where `n` is the current ABI version.")
 if (NOT LIBCXX_ABI_NAMESPACE MATCHES "__.*")
   message(FATAL_ERROR "LIBCXX_ABI_NAMESPACE must be a reserved identifier, got '${LIBCXX_ABI_NAMESPACE}'.")
 endif()
diff --git a/libcxx/include/__config b/libcxx/include/__config
index 63e6eceabd5ec..7e996bbf92ba0 100644
--- a/libcxx/include/__config
+++ b/libcxx/include/__config
@@ -484,21 +484,8 @@ typedef __char32_t char32_t;
 #    define _LIBCPP_EXCEPTIONS_SIG e
 #  endif
 
-#  if !_LIBCPP_HAS_EXCEPTIONS
-#    define _LIBCPP_EXCEPTIONS_SIG n
-#  else
-#    define _LIBCPP_EXCEPTIONS_SIG e
-#  endif
-
-#  if defined(__POINTER_FIELD_PROTECTION__)
-#    define _LIBCPP_PFP_SIG p
-#  else
-#    define _LIBCPP_PFP_SIG
-#  endif
-
 #  define _LIBCPP_ODR_SIGNATURE                                                                                        \
-    _LIBCPP_CONCAT(_LIBCPP_CONCAT(_LIBCPP_CONCAT(_LIBCPP_HARDENING_SIG, _LIBCPP_EXCEPTIONS_SIG), _LIBCPP_PFP_SIG),     \
-                   _LIBCPP_VERSION)
+    _LIBCPP_CONCAT(_LIBCPP_CONCAT(_LIBCPP_HARDENING_SIG, _LIBCPP_EXCEPTIONS_SIG), _LIBCPP_VERSION)
 
 // This macro marks a symbol as being hidden from libc++'s ABI. This is achieved
 // on two levels: