[libcxx] Annotate c++17 aligned new/delete operators with availability attribute

[ahatanak]

Summary

This is needed because older versions of libc++ do not have these operators. If users target an older deployment target and try to compile programs in which these operators are explicitly called, the compiler will complain.

The following is the list of minimum deployment targets for the four OSes:

macosx: 10.13
ios: 11.0
tvos: 11.0
watchos: 4.0

I followed the other availability macros in using "strict", but I'm not sure this was the right decision. The documentation seems to recommend not using "strict" (it says that weakly-linking is almost always a better API choice).

rdar://problem/32664169

[erik.pilkington]

test/std/language.support/support.dynamic/new.delete/new.delete.placement/new_deployment.fail.cpp

35 ↗

(On Diff #103693)

You probably shouldn't include the line numbers here, it makes the test fragile. Ie, do expected-note@new:*

[dexonsmith]

I followed the other availability macros in using "strict", but I'm not sure this was the right decision. The documentation seems to recommend not using "strict" (it says that weakly-linking is almost always a better API choice).

libc++ is one of the exceptions. Use strict.

[dexonsmith]

test/std/language.support/support.dynamic/new.delete/new.delete.placement/new_deployment.fail.cpp

12–16 ↗

(On Diff #103693)

There is a lit configuration to choose whether to run with availability or not. We should just mark the test unsupported when we don't want it to run.

It's also important to run the rest of the suite with availability turned on, to see which other tests start to fail.

21–26 ↗

(On Diff #103693)

Similarly here, we can just mark the test unsupported when we don't have availability turned on or we're targeting 10.13 or later.

[ahatanak]

Address review comments.

test/std/language.support/support.dynamic/new.delete/new.delete.placement/new_deployment.fail.cpp

12–16 ↗

(On Diff #103693)

I added "REQUIRES: availability=macosx10.12" to avoid running this test when availability is turned off or we are targeting 10.13 or later.

I ran the tests with availability turned on and they all passed.

[ahatanak]

Fix line number and remove #else.

[dexonsmith]

LGTM.

[mclow.lists]

This doesn't work when running the libc++ tests against a non-system libc++. (which is what all the libc++ developers and AND all the test bots do)

[ahatanak]

I'm not exactly sure why the test failed, but the patch was reverted in r306859.

[mclow.lists]

I'm not exactly sure why the test failed, but the patch was reverted in r306859.

My bad, since the tests are failing due to clang whining about the system dylib not supporting aligned new/delete on 10.12, I meant to post this on D34574

libcxx/trunk/include/__config

#define _LIBCPP_AVAILABILITY_TYPEINFO_VTABLE                                   \
   __attribute__((availability(macosx,strict,introduced=10.9)))                 \
   __attribute__((availability(ios,strict,introduced=7.0)))
 #define _LIBCPP_AVAILABILITY_LOCALE_CATEGORY                                   \
   __attribute__((availability(macosx,strict,introduced=10.9)))                 \
   __attribute__((availability(ios,strict,introduced=7.0)))
 #define _LIBCPP_AVAILABILITY_ATOMIC_SHARED_PTR                                 \
   __attribute__((availability(macosx,strict,introduced=10.9)))                 \
   __attribute__((availability(ios,strict,introduced=7.0)))
+#define _LIBCPP_AVAILABILITY_ALIGNED_ALLOCATION                                \
+  __attribute__((availability(macosx,strict,introduced=10.13)))                \
+  __attribute__((availability(ios,strict,introduced=11.0)))                    \
+  __attribute__((availability(tvos,strict,introduced=11.0)))                   \
+  __attribute__((availability(watchos,strict,introduced=4.0)))
 #else
 #define _LIBCPP_AVAILABILITY_SHARED_MUTEX
 #define _LIBCPP_AVAILABILITY_BAD_OPTIONAL_ACCESS
 #define _LIBCPP_AVAILABILITY_BAD_ARRAY_LENGTH
 #define _LIBCPP_AVAILABILITY_BAD_ANY_CAST
 #define _LIBCPP_AVAILABILITY_UNCAUGHT_EXCEPTIONS
 #define _LIBCPP_AVAILABILITY_SIZED_NEW_DELETE
 #define _LIBCPP_AVAILABILITY_FUTURE_ERROR
 #define _LIBCPP_AVAILABILITY_TYPEINFO_VTABLE
 #define _LIBCPP_AVAILABILITY_LOCALE_CATEGORY
 #define _LIBCPP_AVAILABILITY_ATOMIC_SHARED_PTR
+#define _LIBCPP_AVAILABILITY_ALIGNED_ALLOCATION
 #endif
 
 // Define availability that depends on _LIBCPP_NO_EXCEPTIONS.
 #ifdef _LIBCPP_NO_EXCEPTIONS
 #define _LIBCPP_AVAILABILITY_DYNARRAY
 #define _LIBCPP_AVAILABILITY_FUTURE
 #define _LIBCPP_AVAILABILITY_THROW_BAD_ANY_CAST
 #else

libcxx/trunk/include/new

 _LIBCPP_OVERRIDABLE_FUNC_VIS void* operator new[](std::size_t __sz, const std::nothrow_t&) _NOEXCEPT _NOALIAS;
 _LIBCPP_OVERRIDABLE_FUNC_VIS void  operator delete[](void* __p) _NOEXCEPT;
 _LIBCPP_OVERRIDABLE_FUNC_VIS void  operator delete[](void* __p, const std::nothrow_t&) _NOEXCEPT;
 #ifndef _LIBCPP_HAS_NO_SIZED_DEALLOCATION
 _LIBCPP_OVERRIDABLE_FUNC_VIS _LIBCPP_AVAILABILITY_SIZED_NEW_DELETE void  operator delete[](void* __p, std::size_t __sz) _NOEXCEPT;
 #endif
 
 #ifndef _LIBCPP_HAS_NO_ALIGNED_ALLOCATION
-_LIBCPP_OVERRIDABLE_FUNC_VIS void* operator new(std::size_t __sz, std::align_val_t) _THROW_BAD_ALLOC;
-_LIBCPP_OVERRIDABLE_FUNC_VIS void* operator new(std::size_t __sz, std::align_val_t, const std::nothrow_t&) _NOEXCEPT _NOALIAS;
-_LIBCPP_OVERRIDABLE_FUNC_VIS void  operator delete(void* __p, std::align_val_t) _NOEXCEPT;
-_LIBCPP_OVERRIDABLE_FUNC_VIS void  operator delete(void* __p, std::align_val_t, const std::nothrow_t&) _NOEXCEPT;
+_LIBCPP_OVERRIDABLE_FUNC_VIS _LIBCPP_AVAILABILITY_ALIGNED_ALLOCATION void* operator new(std::size_t __sz, std::align_val_t) _THROW_BAD_ALLOC;
+_LIBCPP_OVERRIDABLE_FUNC_VIS _LIBCPP_AVAILABILITY_ALIGNED_ALLOCATION void* operator new(std::size_t __sz, std::align_val_t, const std::nothrow_t&) _NOEXCEPT _NOALIAS;
+_LIBCPP_OVERRIDABLE_FUNC_VIS _LIBCPP_AVAILABILITY_ALIGNED_ALLOCATION void  operator delete(void* __p, std::align_val_t) _NOEXCEPT;
+_LIBCPP_OVERRIDABLE_FUNC_VIS _LIBCPP_AVAILABILITY_ALIGNED_ALLOCATION void  operator delete(void* __p, std::align_val_t, const std::nothrow_t&) _NOEXCEPT;
 #ifndef _LIBCPP_HAS_NO_SIZED_DEALLOCATION
-_LIBCPP_OVERRIDABLE_FUNC_VIS _LIBCPP_AVAILABILITY_SIZED_NEW_DELETE void  operator delete(void* __p, std::size_t __sz, std::align_val_t) _NOEXCEPT;
+_LIBCPP_OVERRIDABLE_FUNC_VIS _LIBCPP_AVAILABILITY_ALIGNED_ALLOCATION void  operator delete(void* __p, std::size_t __sz, std::align_val_t) _NOEXCEPT;
 #endif
 
-_LIBCPP_OVERRIDABLE_FUNC_VIS void* operator new[](std::size_t __sz, std::align_val_t) _THROW_BAD_ALLOC;
-_LIBCPP_OVERRIDABLE_FUNC_VIS void* operator new[](std::size_t __sz, std::align_val_t, const std::nothrow_t&) _NOEXCEPT _NOALIAS;
-_LIBCPP_OVERRIDABLE_FUNC_VIS void  operator delete[](void* __p, std::align_val_t) _NOEXCEPT;
-_LIBCPP_OVERRIDABLE_FUNC_VIS void  operator delete[](void* __p, std::align_val_t, const std::nothrow_t&) _NOEXCEPT;
+_LIBCPP_OVERRIDABLE_FUNC_VIS _LIBCPP_AVAILABILITY_ALIGNED_ALLOCATION void* operator new[](std::size_t __sz, std::align_val_t) _THROW_BAD_ALLOC;
+_LIBCPP_OVERRIDABLE_FUNC_VIS _LIBCPP_AVAILABILITY_ALIGNED_ALLOCATION void* operator new[](std::size_t __sz, std::align_val_t, const std::nothrow_t&) _NOEXCEPT _NOALIAS;
+_LIBCPP_OVERRIDABLE_FUNC_VIS _LIBCPP_AVAILABILITY_ALIGNED_ALLOCATION void  operator delete[](void* __p, std::align_val_t) _NOEXCEPT;
+_LIBCPP_OVERRIDABLE_FUNC_VIS _LIBCPP_AVAILABILITY_ALIGNED_ALLOCATION void  operator delete[](void* __p, std::align_val_t, const std::nothrow_t&) _NOEXCEPT;
 #ifndef _LIBCPP_HAS_NO_SIZED_DEALLOCATION
-_LIBCPP_OVERRIDABLE_FUNC_VIS _LIBCPP_AVAILABILITY_SIZED_NEW_DELETE void  operator delete[](void* __p, std::size_t __sz, std::align_val_t) _NOEXCEPT;
+_LIBCPP_OVERRIDABLE_FUNC_VIS _LIBCPP_AVAILABILITY_ALIGNED_ALLOCATION void  operator delete[](void* __p, std::size_t __sz, std::align_val_t) _NOEXCEPT;
 #endif
 #endif
 
 inline _LIBCPP_INLINE_VISIBILITY void* operator new  (std::size_t, void* __p) _NOEXCEPT {return __p;}
 inline _LIBCPP_INLINE_VISIBILITY void* operator new[](std::size_t, void* __p) _NOEXCEPT {return __p;}
 inline _LIBCPP_INLINE_VISIBILITY void  operator delete  (void*, void*) _NOEXCEPT {}
 inline _LIBCPP_INLINE_VISIBILITY void  operator delete[](void*, void*) _NOEXCEPT {}
 

libcxx/trunk/test/std/language.support/support.dynamic/new.delete/new.delete.placement/new_deployment.fail.cpp

+//===----------------------------------------------------------------------===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is dual licensed under the MIT and the University of Illinois Open
+// Source Licenses. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+
+// UNSUPPORTED: c++98, c++03, c++11, c++14
+// REQUIRES: availability=macosx10.12
+
+// test availability of new/delete operators introduced in c++17.
+
+#include <new>
+
+int main () {
+  int *p0 = new ((std::align_val_t)16) int(1);
+  (void)p0;
+  int *p1 = new ((std::align_val_t)16) int[1];
+  (void)p1;
+  // expected-error@-4 {{call to unavailable function 'operator new': introduced in macOS 10.13}}
+  // expected-note@new:* {{candidate function has been explicitly made unavailable}}
+  // expected-note@new:* {{candidate function not viable: no known conversion from 'std::align_val_t' to 'const std::nothrow_t' for 2nd argument}}
+  // expected-note@new:* {{candidate function not viable: no known conversion from 'std::align_val_t' to 'void *' for 2nd argument}}
+  // expected-note@new:* {{candidate function not viable: requires single argument '__sz', but 2 arguments were provided}}
+  // expected-note@new:* {{candidate function not viable: requires 3 arguments, but 2 were provided}}
+
+  // expected-error@-9 {{call to unavailable function 'operator new[]': introduced in macOS 10.13}}
+  // expected-note@new:* {{candidate function has been explicitly made unavailable}}
+  // expected-note@new:* {{candidate function not viable: no known conversion from 'std::align_val_t' to 'const std::nothrow_t' for 2nd argument}}
+  // expected-note@new:* {{candidate function not viable: no known conversion from 'std::align_val_t' to 'void *' for 2nd argument}}
+  // expected-note@new:* {{candidate function not viable: requires single argument '__sz', but 2 arguments were provided}}
+  // expected-note@new:* {{candidate function not viable: requires 3 arguments, but 2 were provided}}
+  return 0;
+}