The application of constexpr to __construct_at triggers weird linker
errors when building LLVM with modules enabled and C++ < 20.
> ld.lld: error: undefined hidden symbol: void*
std::__1::__voidify[abi:nn190000]<llvm::sys::ProcessStatistics>(llvm::sys::ProcessStatistics&)
>>>> referenced by construct_at.h:52
(/usr/local/bin/../include/c++/v1/__memory/construct_at.h:52)
>>>> Program.cpp.o:(llvm::sys::Wait(llvm::sys::ProcessInfo const&,
std::__1::optional<unsigned int>, std::__1::basic_string<char,
std::__1::char_traits<char>, std::__1::allocator<char>>*,
std::__1::optional<llvm::sys::ProcessStatistics>*, bool)) in archive
lib/libLLVMSupport.a
I suspect this is related to undefined behavior caused by the fact that
construct_at is never really constexpr (which is UB NDR).
I'm unsure how to meaningfully write a test for this, as I haven't been
able to trigger it in smaller unit tests
The exposition-only type trait `pair-like` includes `ranges::subrange`,
but in every single case excludes `ranges::subrange` from the list. This
patch introduces two new traits `__tuple_like_no_subrange` and
`__pair_like_no_subrange`, which exclude `ranges::subrange` from the
possible matches. `__pair_like` is no longer required, and thus removed.
`__tuple_like` is implemented as `__tuple_like_no_subrange` or a
`ranges::subrange` specialization.
Fixes#75975.
Remove `_LIBCPP_ENABLE_CXX20_REMOVED_ALLOCATOR_MEMBERS` for the LLVM 19
release, it was previously marked as deprecated in LLVM 18.
I believe that
`_LIBCPP_ENABLE_CXX20_REMOVED_ALLOCATOR_VOID_SPECIALIZATION` was only
used by Google in conjunction with
`_LIBCPP_ENABLE_CXX20_REMOVED_ALLOCATOR_MEMBERS`.
Removing both macros together should not cause any issues in practice,
even though we did not announce the removal of
`_LIBCPP_ENABLE_CXX20_REMOVED_ALLOCATOR_VOID_SPECIALIZATION` before.
These headers have become very small by using compiler builtins, often
containing only two declarations. This merges these headers, since
there doesn't seem to be much of a benefit keeping them separate.
Specifically, `is_{,_nothrow,_trivially}{assignable,constructible}` are
kept and the `copy`, `move` and `default` versions of these type traits
are moved in to the respective headers.
#80558 introduced code that assumed that the element type of `vector` is
never const. This fixes it and adds a test. Eventually we should remove
the `allocator<const T>` extension.
This patch introduces a new trait to represent whether a type is
trivially
relocatable, and uses that trait to optimize the growth of a std::vector
of trivially relocatable objects.
```
--------------------------------------------------
Benchmark old new
--------------------------------------------------
bm_grow<int> 1354 ns 1301 ns
bm_grow<std::string> 5584 ns 3370 ns
bm_grow<std::unique_ptr<int>> 3506 ns 1994 ns
bm_grow<std::deque<int>> 27114 ns 27209 ns
```
This also changes to order of moving and destroying the objects when
growing the vector. This should not affect our conformance.
We recently noticed that the unwrap_iter.h file was pushing macros, but
it was pushing them again instead of popping them at the end of the
file. This led to libc++ basically swallowing any custom definition of
these macros in user code:
#define min HELLO
#include <algorithm>
// min is not HELLO anymore, it's not defined
While investigating this issue, I noticed that our push/pop pragmas were
actually entirely wrong too. Indeed, instead of pushing macros like
`move`, we'd push `move(int, int)` in the pragma, which is not a valid
macro name. As a result, we would not actually push macros like `move`
-- instead we'd simply undefine them. This led to the following code not
working:
#define move HELLO
#include <algorithm>
// move is not HELLO anymore
Fixing the pragma push/pop incantations led to a cascade of issues
because we use identifiers like `move` in a large number of places, and
all of these headers would now need to do the push/pop dance.
This patch fixes all these issues. First, it adds a check that we don't
swallow important names like min, max, move or refresh as explained
above. This is done by augmenting the existing
system_reserved_names.gen.py test to also check that the macros are what
we expect after including each header.
Second, it fixes the push/pop pragmas to work properly and adds missing
pragmas to all the files I could detect a failure in via the newly added
test.
rdar://121365472
Introduce a new `argument-within-domain` category that covers cases
where the given arguments make it impossible to produce a correct result
(or create a valid object in case of constructors). While the incorrect
result doesn't create an immediate problem within the library (like e.g.
a null pointer dereference would), it always indicates a logic error in
user code and is highly likely to lead to a bug in the program once the
value is used.
As described in #69994, using the escape hatch makes us non-conforming
in C++20 due to incorrect constexpr-ness. It also leads to bad
diagnostics as reported by #63900. We discussed the issue in the libc++
monthly meeting and we agreed that we should deprecate the macro in LLVM
18, and then remove it in LLVM 19 since it causes too many problems.
This patch does the first part of this -- it deprecates the macro.
Fixes#69994Fixes#63900
Partially addresses #75975
This was causing compilation errors when attempting to compare a
`shared_ptr<T[]>` with `nullptr`, as `get()` returns `T*` rather than `T
(*)[]`. `unique_ptr` did not have this issue, but I've added tests to
make sure.
The status table incorrectly marks P0521R0 as nothing to do. This is not
correct the function should be deprecated.
During our latest monthly meeting we argreed to remove the
_LIBCPP_ENABLE_CXXyy_REMOVED_FEATURES macros, therefore the new macro is
not
added to that global list.
Implements
- P0521R0 Proposed Resolution for CA 14 (shared_ptr use_count/unique)
Implements parts of
- P0619R4 Reviewing Deprecated Facilities of C++17 for C++20
---------
Co-authored-by: Nikolas Klauser <nikolasklauser@berlin.de>
This patch runs clang-format on all of libcxx/include and libcxx/src, in
accordance with the RFC discussed at [1]. Follow-up patches will format
the benchmarks, the test suite and remaining parts of the code. I'm
splitting this one into its own patch so the diff is a bit easier to
review.
This patch was generated with:
find libcxx/include libcxx/src -type f \
| grep -v 'module.modulemap.in' \
| grep -v 'CMakeLists.txt' \
| grep -v 'README.txt' \
| grep -v 'libcxx.imp' \
| grep -v '__config_site.in' \
| xargs clang-format -i
A Git merge driver is available in libcxx/utils/clang-format-merge-driver.sh
to help resolve merge and rebase issues across these formatting changes.
[1]: https://discourse.llvm.org/t/rfc-clang-formatting-all-of-libc-once-and-for-all
In preparation for running clang-format on the whole code base, we are
also removing mentions of the legacy _LIBCPP_INLINE_VISIBILITY macro in
favor of the newer _LIBCPP_HIDE_FROM_ABI.
We're still leaving the definition of _LIBCPP_INLINE_VISIBILITY to avoid
creating needless breakage in case some older patches are checked-in
with mentions of the old macro. After we branch for LLVM 18, we can do
another pass to clean up remaining uses of the macro that might have
gotten introduced by mistake (if any) and remove the macro itself at the
same time. This is just a minor convenience to smooth out the transition
as much as possible.
See
https://discourse.llvm.org/t/rfc-clang-formatting-all-of-libc-once-and-for-all
for the clang-format proposal.
This commit removes checks like `_LIBCPP_CLANG_VER >= 1600` related to
ASan annotations. As only 2 previous versions are supported, it's a TODO
for LLVM 18.
Before this patch, we would fail to implicitly convert the result of
predicates to bool, which means we'd potentially perform a copy or move
construction of the boolean-testable, which isn't allowed. The same
holds true for comparing iterators against sentinels, which is allowed
to return a boolean-testable type.
We already had tests aiming to ensure correct handling of these types,
but they failed to provide appropriate coverage in several cases due to
guaranteed RVO. This patch fixes the tests, adds tests for missing
algorithms and views, and fixes the actual problems in the code.
Fixes#69074
According to https://developer.apple.com/support/xcode/, quite a few of
our availability macros don't do anything anymore, so we might as well
remove them to clean up the code a bit.
There is no reason to use `alignment_of<T>` instead of `alignof(T)` or
`_LIBCPP_ALIGNOF(T)`. It only makes the code more verbose and results in
slightly worse compile times.
If an iterator passed to std::uninitialized_copy & friends provided an
unconstrained comparison operator, we would trigger an ambiguous
overload resolution because we used to compare against
__unreachable_sentinel in our implementation.
This patch fixes that by only comparing the output iterator when it is
actually required, i.e. in the <ranges> versions of the algorithms.
Fixes#69334
Fixes#68051.
Current implementation passes the number of `_AlignedStorage` objects
when it calls to `allocate` and the number of **bytes** on `deallocate`.
This only applies to allocations that allocate control block and the
storage together, i.e. `make_shared` and `allocate_shared`.
Found by ASan under Clang combined with `-fsized-deallocation`.
When we implemented C++20's P0674R1, we didn't enable the part of
P0674R1 that was resolving LWG2070 as a DR. This patch fixes that and
makes sure that we consistently go through the allocator when
constructing and destroying the underlying object in
std::allocate_shared.
Fixes#54365.
This brings most of the enable_ifs in libc++ to the same style.
Reviewed By: #libc, ldionne
Spies: ldionne, libcxx-commits
Differential Revision: https://reviews.llvm.org/D157753
This brings most of the enable_ifs in libc++ to the same style. It also has the nice side-effect of reducing the size of names of these symbols, since the arguments don't get mangled anymore.
Reviewed By: #libc, Mordante
Spies: Mordante, libcxx-commits
Differential Revision: https://reviews.llvm.org/D157748
This brings most of the enable_ifs in libc++ to the same style. It also has the nice side-effect of reducing the size of names of these symbols, since the depedent return type is shorter.
Reviewed By: #libc, ldionne
Spies: ldionne, libcxx-commits
Differential Revision: https://reviews.llvm.org/D157736
When inserting nodes into a forward list, each new node is allocated but
not constructed. The constructor was being called explicitly on the node
`value_` but the `next_` pointer remained uninitialized rather than
being set to null. This bug is only triggered in the cleanup code if an
exception is thrown -- upon successful creation of new nodes, the last
incorrect "next" value is overwritten to a correct pointer.
This issue was found due to new tests added in
https://reviews.llvm.org/D149830.
Differential Revision: https://reviews.llvm.org/D152327
POSIX allows certain macros to exist with generic names (i.e. refresh(), move(), and erase()) to exist in `curses.h` which conflict with functions found in std::filesystem, among others. This patch undefs the macros in question and adds them to LIBCPP_PUSH_MACROS and LIBCPP_POP_MACROS.
Reviewed By: #libc, philnik, ldionne
Differential Revision: https://reviews.llvm.org/D147356
This patch reverts the following commits:
015cd317ea (add missing HIDE_FROM_ABI)
420a204d52 (add _LIBCPP_NO_CFI)
31eeba3f7c (add __uninitialized_buffer)
It also reverts a small part of b935ab8e74
which is required to make the stable_partition.pass.cpp test pass on GCC.
Some issues were pointed out in https://reviews.llvm.org/D152208 and
in https://reviews.llvm.org/D154017, so I am reverting this patch
until we have time to weigh the various solutions and get consensus
on the design of the API.
Differential Revision: https://reviews.llvm.org/D154161
Some modules export modules that they don't import (i.e. that their header doesn't directly include). That sometimes works when the exported submodule is in the same module, but when the `std` mega module is broken up (D144322), some of the exports stop working. Make the exports and includes consistent, either by adding includes for the exports, or by removing exports for missing includes.
The `concepts.equality_comparable` export in `std.iterator.__iterator.concepts` isn't doing anything because 1) it's resolved as `std.iterator.__iterator.concepts.equality_comparable` and 2) there's a `__concepts` submodule in between `std.concepts` and `equality_comparable`. Fix it to be `std.concepts.__concepts.equality_comparable`.
<span> is listed in both `std.span` and `std.experimental.span`. Delete the latter module.
There is no `__errc` module or header, so remove that export from `std.system_error`.
Reviewed By: ldionne, #libc
Differential Revision: https://reviews.llvm.org/D153211
Replace most uses of `_LIBCPP_ASSERT` with
`_LIBCPP_ASSERT_UNCATEGORIZED`.
This is done as a prerequisite to introducing hardened mode to libc++.
The idea is to make enabling assertions an opt-in with (somewhat)
fine-grained controls over which categories of assertions are enabled.
The vast majority of assertions are currently uncategorized; the new
macro will allow turning on `_LIBCPP_ASSERT` (the underlying mechanism
for all kinds of assertions) without enabling all the uncategorized
assertions (in the future; this patch preserves the current behavior).
Differential Revision: https://reviews.llvm.org/D153816
