[libcxx-commits] [libcxx] [libc++] Fix std::make_exception_ptr interaction with ObjC (PR #135386)

Louis Dionne via libcxx-commits libcxx-commits at lists.llvm.org
Mon Jul 7 13:52:51 PDT 2025


https://github.com/ldionne updated https://github.com/llvm/llvm-project/pull/135386

>From 9f88c67d226864bd7df99a3e55d4a4790a8d69fa Mon Sep 17 00:00:00 2001
From: Ivan Trofimov <i.trofimow at yandex.ru>
Date: Fri, 11 Apr 2025 18:23:30 +0300
Subject: [PATCH 01/14] fix std::make_exception_ptr interaction with ObjC

---
 libcxx/include/__exception/exception_ptr.h | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/libcxx/include/__exception/exception_ptr.h b/libcxx/include/__exception/exception_ptr.h
index dac5b00b57fe3..8b90a6569d136 100644
--- a/libcxx/include/__exception/exception_ptr.h
+++ b/libcxx/include/__exception/exception_ptr.h
@@ -92,7 +92,7 @@ class _LIBCPP_EXPORTED_FROM_ABI exception_ptr {
 template <class _Ep>
 _LIBCPP_HIDE_FROM_ABI exception_ptr make_exception_ptr(_Ep __e) _NOEXCEPT {
 #  if _LIBCPP_HAS_EXCEPTIONS
-#    if _LIBCPP_AVAILABILITY_HAS_INIT_PRIMARY_EXCEPTION && __cplusplus >= 201103L
+#    if !defined(__OBJC__) && _LIBCPP_AVAILABILITY_HAS_INIT_PRIMARY_EXCEPTION && __cplusplus >= 201103L
   using _Ep2 = __decay_t<_Ep>;
 
   void* __ex = __cxxabiv1::__cxa_allocate_exception(sizeof(_Ep));

>From 764caba12345ab1bc626758d5052c4597cbade62 Mon Sep 17 00:00:00 2001
From: Ivan Trofimov <i.trofimow at yandex.ru>
Date: Mon, 14 Apr 2025 17:17:37 +0300
Subject: [PATCH 02/14] add a comment about __OBJC__ define

---
 libcxx/include/__exception/exception_ptr.h | 1 +
 1 file changed, 1 insertion(+)

diff --git a/libcxx/include/__exception/exception_ptr.h b/libcxx/include/__exception/exception_ptr.h
index 8b90a6569d136..167aa4d9b367a 100644
--- a/libcxx/include/__exception/exception_ptr.h
+++ b/libcxx/include/__exception/exception_ptr.h
@@ -92,6 +92,7 @@ class _LIBCPP_EXPORTED_FROM_ABI exception_ptr {
 template <class _Ep>
 _LIBCPP_HIDE_FROM_ABI exception_ptr make_exception_ptr(_Ep __e) _NOEXCEPT {
 #  if _LIBCPP_HAS_EXCEPTIONS
+  // Clang treats throwing ObjC types differently, and we have to preserve original throw-ing behavior
 #    if !defined(__OBJC__) && _LIBCPP_AVAILABILITY_HAS_INIT_PRIMARY_EXCEPTION && __cplusplus >= 201103L
   using _Ep2 = __decay_t<_Ep>;
 

>From 6e108eb698cccec4202d711ae9795fffb53d5ec8 Mon Sep 17 00:00:00 2001
From: Ivan Trofimov <i.trofimow at yandex.ru>
Date: Wed, 14 May 2025 01:11:01 +0300
Subject: [PATCH 03/14] remove the __OBJC__ usage in favor of checking whether
 the type thrown is a pointer

---
 libcxx/include/__exception/exception_ptr.h | 52 +++++++++++++---------
 1 file changed, 32 insertions(+), 20 deletions(-)

diff --git a/libcxx/include/__exception/exception_ptr.h b/libcxx/include/__exception/exception_ptr.h
index 167aa4d9b367a..e0c6fc48b1333 100644
--- a/libcxx/include/__exception/exception_ptr.h
+++ b/libcxx/include/__exception/exception_ptr.h
@@ -15,6 +15,7 @@
 #include <__memory/addressof.h>
 #include <__memory/construct_at.h>
 #include <__type_traits/decay.h>
+#include <__type_traits/is_pointer.h>
 #include <cstdlib>
 #include <typeinfo>
 
@@ -92,39 +93,50 @@ class _LIBCPP_EXPORTED_FROM_ABI exception_ptr {
 template <class _Ep>
 _LIBCPP_HIDE_FROM_ABI exception_ptr make_exception_ptr(_Ep __e) _NOEXCEPT {
 #  if _LIBCPP_HAS_EXCEPTIONS
+#    if _LIBCPP_AVAILABILITY_HAS_INIT_PRIMARY_EXCEPTION && __cplusplus >= 201703L
   // Clang treats throwing ObjC types differently, and we have to preserve original throw-ing behavior
-#    if !defined(__OBJC__) && _LIBCPP_AVAILABILITY_HAS_INIT_PRIMARY_EXCEPTION && __cplusplus >= 201103L
-  using _Ep2 = __decay_t<_Ep>;
-
-  void* __ex = __cxxabiv1::__cxa_allocate_exception(sizeof(_Ep));
+  // to not break some ObjC invariants. ObjC types are thrown by a pointer, hence the condition;
+  // although it does also trigger for some valid c++ usages, this should be a case rare enough to
+  // not complicate the condition any further
+  if constexpr (std::is_pointer_v<_Ep>) {
+    try {
+      throw __e;
+    } catch (...) {
+      return current_exception();
+    }
+  } else {
+    using _Ep2 = __decay_t<_Ep>;
+
+    void* __ex = __cxxabiv1::__cxa_allocate_exception(sizeof(_Ep));
 #      ifdef __wasm__
-  // In Wasm, a destructor returns its argument
-  (void)__cxxabiv1::__cxa_init_primary_exception(
-      __ex, const_cast<std::type_info*>(&typeid(_Ep)), [](void* __p) -> void* {
+    // In Wasm, a destructor returns its argument
+    (void)__cxxabiv1::__cxa_init_primary_exception(
+        __ex, const_cast<std::type_info*>(&typeid(_Ep)), [](void* __p) -> void* {
 #      else
-  (void)__cxxabiv1::__cxa_init_primary_exception(__ex, const_cast<std::type_info*>(&typeid(_Ep)), [](void* __p) {
+    (void)__cxxabiv1::__cxa_init_primary_exception(__ex, const_cast<std::type_info*>(&typeid(_Ep)), [](void* __p) {
 #      endif
-        std::__destroy_at(static_cast<_Ep2*>(__p));
+          std::__destroy_at(static_cast<_Ep2*>(__p));
 #      ifdef __wasm__
-        return __p;
+          return __p;
 #      endif
-      });
-
-  try {
-    ::new (__ex) _Ep2(__e);
-    return exception_ptr::__from_native_exception_pointer(__ex);
-  } catch (...) {
-    __cxxabiv1::__cxa_free_exception(__ex);
-    return current_exception();
+        });
+
+    try {
+      ::new (__ex) _Ep2(__e);
+      return exception_ptr::__from_native_exception_pointer(__ex);
+    } catch (...) {
+      __cxxabiv1::__cxa_free_exception(__ex);
+      return current_exception();
+    }
   }
-#    else
+#    else // !(_LIBCPP_AVAILABILITY_HAS_INIT_PRIMARY_EXCEPTION && __cplusplus >= 201703L)
   try {
     throw __e;
   } catch (...) {
     return current_exception();
   }
 #    endif
-#  else
+#  else // !LIBCPP_HAS_EXCEPTIONS
   ((void)__e);
   std::abort();
 #  endif

>From a1e858653db7c21dc3ff5ff5ba887d72c6dc1942 Mon Sep 17 00:00:00 2001
From: Ivan Trofimov <i.trofimow at yandex.ru>
Date: Tue, 20 May 2025 14:23:10 +0300
Subject: [PATCH 04/14] relax the c++-standard requirement

---
 libcxx/include/__exception/exception_ptr.h | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/libcxx/include/__exception/exception_ptr.h b/libcxx/include/__exception/exception_ptr.h
index eb791d739e4b6..d38bec7720a5f 100644
--- a/libcxx/include/__exception/exception_ptr.h
+++ b/libcxx/include/__exception/exception_ptr.h
@@ -96,7 +96,7 @@ class _LIBCPP_EXPORTED_FROM_ABI exception_ptr {
 template <class _Ep>
 _LIBCPP_HIDE_FROM_ABI exception_ptr make_exception_ptr(_Ep __e) _NOEXCEPT {
 #  if _LIBCPP_HAS_EXCEPTIONS
-#    if _LIBCPP_AVAILABILITY_HAS_INIT_PRIMARY_EXCEPTION && __cplusplus >= 201703L
+#    if _LIBCPP_AVAILABILITY_HAS_INIT_PRIMARY_EXCEPTION && __cplusplus >= 201103L
   // Clang treats throwing ObjC types differently, and we have to preserve original throw-ing behavior
   // to not break some ObjC invariants. ObjC types are thrown by a pointer, hence the condition;
   // although it does also trigger for some valid c++ usages, this should be a case rare enough to

>From ec0735c8b312bfc89e2bd4c37ba089548619d1be Mon Sep 17 00:00:00 2001
From: Ivan Trofimov <i.trofimow at yandex.ru>
Date: Tue, 10 Jun 2025 16:18:38 +0300
Subject: [PATCH 05/14] fix the closing #else comment typo

---
 libcxx/include/__exception/exception_ptr.h | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/libcxx/include/__exception/exception_ptr.h b/libcxx/include/__exception/exception_ptr.h
index 1142866548e52..485f3a80c13fc 100644
--- a/libcxx/include/__exception/exception_ptr.h
+++ b/libcxx/include/__exception/exception_ptr.h
@@ -131,7 +131,7 @@ _LIBCPP_HIDE_FROM_ABI exception_ptr make_exception_ptr(_Ep __e) _NOEXCEPT {
       return current_exception();
     }
   }
-#    else // !(_LIBCPP_AVAILABILITY_HAS_INIT_PRIMARY_EXCEPTION && __cplusplus >= 201703L)
+#    else // !(_LIBCPP_AVAILABILITY_HAS_INIT_PRIMARY_EXCEPTION && __cplusplus >= 201103L)
   try {
     throw __e;
   } catch (...) {

>From 985f7a602695f4dda168ae011cd0274f59c2a356 Mon Sep 17 00:00:00 2001
From: Louis Dionne <ldionne.2 at gmail.com>
Date: Tue, 1 Jul 2025 13:58:52 -0400
Subject: [PATCH 06/14] Add test

---
 .../function.objects/exceptions.pass.mm       | 42 +++++++++++++++++++
 1 file changed, 42 insertions(+)
 create mode 100644 libcxx/test/libcxx/utilities/function.objects/exceptions.pass.mm

diff --git a/libcxx/test/libcxx/utilities/function.objects/exceptions.pass.mm b/libcxx/test/libcxx/utilities/function.objects/exceptions.pass.mm
new file mode 100644
index 0000000000000..6a737525bb8ce
--- /dev/null
+++ b/libcxx/test/libcxx/utilities/function.objects/exceptions.pass.mm
@@ -0,0 +1,42 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+// This test ensures that we can catch an Objective-C++ exception by type when
+// throwing via `std::rethrow_exception`. See http://llvm.org/PR135089.
+
+// UNSUPPORTED: c++03
+
+// This test requires the Objective-C ARC, which is (only?) available on Darwin
+// out-of-the-box.
+// REQUIRES: has-fobjc-arc && darwin
+
+// ADDITIONAL_COMPILE_FLAGS: -fobjc-arc
+
+#include <cassert>
+#include <exception>
+
+#import <Foundation/Foundation.h>
+
+NSError* RecoverException(const std::exception_ptr& exc) {
+  try {
+    std::rethrow_exception(exc);
+  } catch (NSError* error) {
+    return error;
+  } catch (...) {
+  }
+  return nullptr;
+}
+
+int main(int, char**) {
+  NSError* error         = [NSError errorWithDomain:NSPOSIXErrorDomain code:EPERM userInfo:nil];
+  std::exception_ptr exc = std::make_exception_ptr(error);
+  NSError* recov         = RecoverException(exc);
+  assert(recov != nullptr);
+
+  return 0;
+}

>From e647f47ba7ce400c902841ac107185e111d26e56 Mon Sep 17 00:00:00 2001
From: Louis Dionne <ldionne.2 at gmail.com>
Date: Tue, 1 Jul 2025 14:29:16 -0400
Subject: [PATCH 07/14] Move test to proper location

---
 .../propagation/make_exception_ptr.objc.pass.mm}               | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)
 rename libcxx/test/{libcxx/utilities/function.objects/exceptions.pass.mm => std/language.support/support.exception/propagation/make_exception_ptr.objc.pass.mm} (92%)

diff --git a/libcxx/test/libcxx/utilities/function.objects/exceptions.pass.mm b/libcxx/test/std/language.support/support.exception/propagation/make_exception_ptr.objc.pass.mm
similarity index 92%
rename from libcxx/test/libcxx/utilities/function.objects/exceptions.pass.mm
rename to libcxx/test/std/language.support/support.exception/propagation/make_exception_ptr.objc.pass.mm
index 6a737525bb8ce..3752f1aa7ac83 100644
--- a/libcxx/test/libcxx/utilities/function.objects/exceptions.pass.mm
+++ b/libcxx/test/std/language.support/support.exception/propagation/make_exception_ptr.objc.pass.mm
@@ -7,7 +7,8 @@
 //===----------------------------------------------------------------------===//
 
 // This test ensures that we can catch an Objective-C++ exception by type when
-// throwing via `std::rethrow_exception`. See http://llvm.org/PR135089.
+// throwing an exception created via `std::make_exception_ptr`.
+// See http://llvm.org/PR135089.
 
 // UNSUPPORTED: c++03
 

>From ca8f571a1e93642ac638c3836d817ebdec7c2133 Mon Sep 17 00:00:00 2001
From: Louis Dionne <ldionne.2 at gmail.com>
Date: Wed, 2 Jul 2025 08:38:38 -0400
Subject: [PATCH 08/14] Use is_pointer instead of is_pointer_v

---
 libcxx/include/__exception/exception_ptr.h | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/libcxx/include/__exception/exception_ptr.h b/libcxx/include/__exception/exception_ptr.h
index 485f3a80c13fc..3da194af5b4db 100644
--- a/libcxx/include/__exception/exception_ptr.h
+++ b/libcxx/include/__exception/exception_ptr.h
@@ -100,7 +100,7 @@ _LIBCPP_HIDE_FROM_ABI exception_ptr make_exception_ptr(_Ep __e) _NOEXCEPT {
   // to not break some ObjC invariants. ObjC types are thrown by a pointer, hence the condition;
   // although it does also trigger for some valid c++ usages, this should be a case rare enough to
   // not complicate the condition any further
-  if constexpr (std::is_pointer_v<_Ep>) {
+  if constexpr (is_pointer<_Ep>::value) {
     try {
       throw __e;
     } catch (...) {

>From ddbbe9795fe7a516099908881d14ebe36d8fb429 Mon Sep 17 00:00:00 2001
From: Louis Dionne <ldionne.2 at gmail.com>
Date: Wed, 2 Jul 2025 09:21:08 -0400
Subject: [PATCH 09/14] Refactor the function to be easier to understand

---
 libcxx/include/__exception/exception_ptr.h | 86 ++++++++++++----------
 1 file changed, 48 insertions(+), 38 deletions(-)

diff --git a/libcxx/include/__exception/exception_ptr.h b/libcxx/include/__exception/exception_ptr.h
index 3da194af5b4db..e076fdf4ddb54 100644
--- a/libcxx/include/__exception/exception_ptr.h
+++ b/libcxx/include/__exception/exception_ptr.h
@@ -93,51 +93,61 @@ class _LIBCPP_EXPORTED_FROM_ABI exception_ptr {
 };
 
 template <class _Ep>
-_LIBCPP_HIDE_FROM_ABI exception_ptr make_exception_ptr(_Ep __e) _NOEXCEPT {
-#  if _LIBCPP_HAS_EXCEPTIONS
-#    if _LIBCPP_AVAILABILITY_HAS_INIT_PRIMARY_EXCEPTION && __cplusplus >= 201103L
-  // Clang treats throwing ObjC types differently, and we have to preserve original throw-ing behavior
-  // to not break some ObjC invariants. ObjC types are thrown by a pointer, hence the condition;
-  // although it does also trigger for some valid c++ usages, this should be a case rare enough to
-  // not complicate the condition any further
-  if constexpr (is_pointer<_Ep>::value) {
-    try {
-      throw __e;
-    } catch (...) {
-      return current_exception();
-    }
-  } else {
-    using _Ep2 = __decay_t<_Ep>;
-
-    void* __ex = __cxxabiv1::__cxa_allocate_exception(sizeof(_Ep));
-#      ifdef __wasm__
-    // In Wasm, a destructor returns its argument
-    (void)__cxxabiv1::__cxa_init_primary_exception(
-        __ex, const_cast<std::type_info*>(&typeid(_Ep)), [](void* __p) -> void* {
-#      else
-    (void)__cxxabiv1::__cxa_init_primary_exception(__ex, const_cast<std::type_info*>(&typeid(_Ep)), [](void* __p) {
-#      endif
-          std::__destroy_at(static_cast<_Ep2*>(__p));
-#      ifdef __wasm__
-          return __p;
-#      endif
-        });
-
-    try {
-      ::new (__ex) _Ep2(__e);
-      return exception_ptr::__from_native_exception_pointer(__ex);
-    } catch (...) {
-      __cxxabiv1::__cxa_free_exception(__ex);
-      return current_exception();
-    }
+_LIBCPP_HIDE_FROM_ABI exception_ptr __make_exception_ptr_explicit(_Ep& __e) _NOEXCEPT {
+  using _Ep2 = __decay_t<_Ep>;
+  void* __ex = __cxxabiv1::__cxa_allocate_exception(sizeof(_Ep));
+#  ifdef __wasm__
+  auto __cleanup = [](void* __p) -> void* {
+    std::__destroy_at(static_cast<_Ep2*>(__p));
+    return __p;
+  };
+#  else
+  auto __cleanup = [](void* __p) { std::__destroy_at(static_cast<_Ep2*>(__p)); };
+#  endif
+  (void)__cxxabiv1::__cxa_init_primary_exception(__ex, const_cast<std::type_info*>(&typeid(_Ep)), __cleanup);
+
+  try {
+    ::new (__ex) _Ep2(__e);
+    return exception_ptr::__from_native_exception_pointer(__ex);
+  } catch (...) {
+    __cxxabiv1::__cxa_free_exception(__ex);
+    return current_exception();
   }
-#    else // !(_LIBCPP_AVAILABILITY_HAS_INIT_PRIMARY_EXCEPTION && __cplusplus >= 201103L)
+}
+
+template <class _Ep>
+_LIBCPP_HIDE_FROM_ABI exception_ptr __make_exception_ptr_via_throw(_Ep& __e) _NOEXCEPT {
   try {
     throw __e;
   } catch (...) {
     return current_exception();
   }
+}
+
+template <class _Ep>
+_LIBCPP_HIDE_FROM_ABI exception_ptr make_exception_ptr(_Ep __e) _NOEXCEPT {
+#  if _LIBCPP_HAS_EXCEPTIONS
+  // Objective-C exceptions are thrown via pointer. When throwing an Objective-C exception,
+  // Clang generates a call to `objc_exception_throw` instead of the usual `__cxa_throw`.
+  // That function creates an exception with a special Objective-C typeinfo instead of
+  // the usual C++ typeinfo, since that is needed to implement the behavior documented
+  // at [1]).
+  //
+  // Because of this special behavior, we can't create an exception via `__cxa_init_primary_exception`
+  // for Objective-C exceptions, otherwise we'd bypass `objc_exception_throw`. See https://llvm.org/PR135089.
+  //
+  // [1]:
+  // https://developer.apple.com/library/archive/documentation/Cocoa/Conceptual/Exceptions/Articles/Exceptions64Bit.html
+  if constexpr (is_pointer<_Ep>::value) {
+    return std::__make_exception_ptr_via_throw(__e);
+  }
+
+#    if _LIBCPP_AVAILABILITY_HAS_INIT_PRIMARY_EXCEPTION && __cplusplus >= 201103L
+  return std::__make_exception_ptr_explicit(__e);
+#    else
+  return std::__make_exception_ptr_via_throw(__e);
 #    endif
+
 #  else // !LIBCPP_HAS_EXCEPTIONS
   ((void)__e);
   std::abort();

>From 3808d880070affebdb2b03fbdf8dc49289fb99e0 Mon Sep 17 00:00:00 2001
From: Louis Dionne <ldionne.2 at gmail.com>
Date: Wed, 2 Jul 2025 09:23:08 -0400
Subject: [PATCH 10/14] Fix broken friend

---
 libcxx/include/__exception/exception_ptr.h | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/libcxx/include/__exception/exception_ptr.h b/libcxx/include/__exception/exception_ptr.h
index e076fdf4ddb54..f287c05b33dc7 100644
--- a/libcxx/include/__exception/exception_ptr.h
+++ b/libcxx/include/__exception/exception_ptr.h
@@ -63,7 +63,7 @@ class _LIBCPP_EXPORTED_FROM_ABI exception_ptr {
   static exception_ptr __from_native_exception_pointer(void*) _NOEXCEPT;
 
   template <class _Ep>
-  friend _LIBCPP_HIDE_FROM_ABI exception_ptr make_exception_ptr(_Ep) _NOEXCEPT;
+  friend _LIBCPP_HIDE_FROM_ABI exception_ptr __make_exception_ptr_explicit(_Ep&) _NOEXCEPT;
 
 public:
   // exception_ptr is basically a COW string so it is trivially relocatable.

>From f587c7191b0c14a1ca8ab5b572f40a1af4abb397 Mon Sep 17 00:00:00 2001
From: Louis Dionne <ldionne.2 at gmail.com>
Date: Wed, 2 Jul 2025 09:35:54 -0400
Subject: [PATCH 11/14] Fix C++03

---
 libcxx/include/__exception/exception_ptr.h | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/libcxx/include/__exception/exception_ptr.h b/libcxx/include/__exception/exception_ptr.h
index f287c05b33dc7..ddf1271a734b2 100644
--- a/libcxx/include/__exception/exception_ptr.h
+++ b/libcxx/include/__exception/exception_ptr.h
@@ -138,7 +138,7 @@ _LIBCPP_HIDE_FROM_ABI exception_ptr make_exception_ptr(_Ep __e) _NOEXCEPT {
   //
   // [1]:
   // https://developer.apple.com/library/archive/documentation/Cocoa/Conceptual/Exceptions/Articles/Exceptions64Bit.html
-  if constexpr (is_pointer<_Ep>::value) {
+  if _LIBCPP_CONSTEXPR (is_pointer<_Ep>::value) {
     return std::__make_exception_ptr_via_throw(__e);
   }
 

>From 860bec26c216299e74ca7d37b585e43d2f0b7d80 Mon Sep 17 00:00:00 2001
From: Louis Dionne <ldionne.2 at gmail.com>
Date: Wed, 2 Jul 2025 09:38:24 -0400
Subject: [PATCH 12/14] More C++03

---
 libcxx/include/__exception/exception_ptr.h | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/libcxx/include/__exception/exception_ptr.h b/libcxx/include/__exception/exception_ptr.h
index ddf1271a734b2..25cda11af4747 100644
--- a/libcxx/include/__exception/exception_ptr.h
+++ b/libcxx/include/__exception/exception_ptr.h
@@ -142,7 +142,7 @@ _LIBCPP_HIDE_FROM_ABI exception_ptr make_exception_ptr(_Ep __e) _NOEXCEPT {
     return std::__make_exception_ptr_via_throw(__e);
   }
 
-#    if _LIBCPP_AVAILABILITY_HAS_INIT_PRIMARY_EXCEPTION && __cplusplus >= 201103L
+#    if _LIBCPP_AVAILABILITY_HAS_INIT_PRIMARY_EXCEPTION && !defined(_LIBCPP_CXX03_LANG)
   return std::__make_exception_ptr_explicit(__e);
 #    else
   return std::__make_exception_ptr_via_throw(__e);

>From 455abac62421992aa083aca5e64dea57bc7933e8 Mon Sep 17 00:00:00 2001
From: Louis Dionne <ldionne.2 at gmail.com>
Date: Wed, 2 Jul 2025 12:22:03 -0400
Subject: [PATCH 13/14] Fix issue with -fno-exceptions

---
 libcxx/include/__exception/exception_ptr.h      | 17 +++++++++--------
 .../propagation/make_exception_ptr.objc.pass.mm |  1 +
 2 files changed, 10 insertions(+), 8 deletions(-)

diff --git a/libcxx/include/__exception/exception_ptr.h b/libcxx/include/__exception/exception_ptr.h
index 25cda11af4747..1256a2de2395b 100644
--- a/libcxx/include/__exception/exception_ptr.h
+++ b/libcxx/include/__exception/exception_ptr.h
@@ -92,18 +92,19 @@ class _LIBCPP_EXPORTED_FROM_ABI exception_ptr {
   friend _LIBCPP_EXPORTED_FROM_ABI void rethrow_exception(exception_ptr);
 };
 
+#  if _LIBCPP_HAS_EXCEPTIONS
 template <class _Ep>
 _LIBCPP_HIDE_FROM_ABI exception_ptr __make_exception_ptr_explicit(_Ep& __e) _NOEXCEPT {
   using _Ep2 = __decay_t<_Ep>;
   void* __ex = __cxxabiv1::__cxa_allocate_exception(sizeof(_Ep));
-#  ifdef __wasm__
+#    ifdef __wasm__
   auto __cleanup = [](void* __p) -> void* {
     std::__destroy_at(static_cast<_Ep2*>(__p));
     return __p;
   };
-#  else
+#    else
   auto __cleanup = [](void* __p) { std::__destroy_at(static_cast<_Ep2*>(__p)); };
-#  endif
+#    endif
   (void)__cxxabiv1::__cxa_init_primary_exception(__ex, const_cast<std::type_info*>(&typeid(_Ep)), __cleanup);
 
   try {
@@ -126,7 +127,6 @@ _LIBCPP_HIDE_FROM_ABI exception_ptr __make_exception_ptr_via_throw(_Ep& __e) _NO
 
 template <class _Ep>
 _LIBCPP_HIDE_FROM_ABI exception_ptr make_exception_ptr(_Ep __e) _NOEXCEPT {
-#  if _LIBCPP_HAS_EXCEPTIONS
   // Objective-C exceptions are thrown via pointer. When throwing an Objective-C exception,
   // Clang generates a call to `objc_exception_throw` instead of the usual `__cxa_throw`.
   // That function creates an exception with a special Objective-C typeinfo instead of
@@ -147,12 +147,13 @@ _LIBCPP_HIDE_FROM_ABI exception_ptr make_exception_ptr(_Ep __e) _NOEXCEPT {
 #    else
   return std::__make_exception_ptr_via_throw(__e);
 #    endif
-
-#  else // !LIBCPP_HAS_EXCEPTIONS
-  ((void)__e);
+}
+#  else  // !_LIBCPP_HAS_EXCEPTIONS
+template <class _Ep>
+_LIBCPP_HIDE_FROM_ABI exception_ptr make_exception_ptr(_Ep) _NOEXCEPT {
   std::abort();
-#  endif
 }
+#  endif // _LIBCPP_HAS_EXCEPTIONS
 
 #else // _LIBCPP_ABI_MICROSOFT
 
diff --git a/libcxx/test/std/language.support/support.exception/propagation/make_exception_ptr.objc.pass.mm b/libcxx/test/std/language.support/support.exception/propagation/make_exception_ptr.objc.pass.mm
index 3752f1aa7ac83..05a6698ea1a59 100644
--- a/libcxx/test/std/language.support/support.exception/propagation/make_exception_ptr.objc.pass.mm
+++ b/libcxx/test/std/language.support/support.exception/propagation/make_exception_ptr.objc.pass.mm
@@ -10,6 +10,7 @@
 // throwing an exception created via `std::make_exception_ptr`.
 // See http://llvm.org/PR135089.
 
+// UNSUPPORTED: no-exceptions
 // UNSUPPORTED: c++03
 
 // This test requires the Objective-C ARC, which is (only?) available on Darwin

>From d8d66b9437ba901dcdaf43b877e34da38c696c6a Mon Sep 17 00:00:00 2001
From: Louis Dionne <ldionne.2 at gmail.com>
Date: Mon, 7 Jul 2025 16:52:30 -0400
Subject: [PATCH 14/14] Fix forgotten conditional for back-deployment

---
 libcxx/include/__exception/exception_ptr.h | 8 +++++---
 1 file changed, 5 insertions(+), 3 deletions(-)

diff --git a/libcxx/include/__exception/exception_ptr.h b/libcxx/include/__exception/exception_ptr.h
index 1256a2de2395b..796fa924be121 100644
--- a/libcxx/include/__exception/exception_ptr.h
+++ b/libcxx/include/__exception/exception_ptr.h
@@ -93,18 +93,19 @@ class _LIBCPP_EXPORTED_FROM_ABI exception_ptr {
 };
 
 #  if _LIBCPP_HAS_EXCEPTIONS
+#    if _LIBCPP_AVAILABILITY_HAS_INIT_PRIMARY_EXCEPTION
 template <class _Ep>
 _LIBCPP_HIDE_FROM_ABI exception_ptr __make_exception_ptr_explicit(_Ep& __e) _NOEXCEPT {
   using _Ep2 = __decay_t<_Ep>;
   void* __ex = __cxxabiv1::__cxa_allocate_exception(sizeof(_Ep));
-#    ifdef __wasm__
+#      ifdef __wasm__
   auto __cleanup = [](void* __p) -> void* {
     std::__destroy_at(static_cast<_Ep2*>(__p));
     return __p;
   };
-#    else
+#      else
   auto __cleanup = [](void* __p) { std::__destroy_at(static_cast<_Ep2*>(__p)); };
-#    endif
+#      endif
   (void)__cxxabiv1::__cxa_init_primary_exception(__ex, const_cast<std::type_info*>(&typeid(_Ep)), __cleanup);
 
   try {
@@ -115,6 +116,7 @@ _LIBCPP_HIDE_FROM_ABI exception_ptr __make_exception_ptr_explicit(_Ep& __e) _NOE
     return current_exception();
   }
 }
+#    endif
 
 template <class _Ep>
 _LIBCPP_HIDE_FROM_ABI exception_ptr __make_exception_ptr_via_throw(_Ep& __e) _NOEXCEPT {



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