184 Commits

Author SHA1 Message Date
Vinay Deshmukh
d286f2ef55
[libc++] Make std::__tree_node member private to prepare for UB removal (#154225)
Prepare for:
https://github.com/llvm/llvm-project/pull/153908#discussion_r2281756219
2025-08-19 11:27:56 +02:00
A. Jiang
7ae1424286
[libc++] Fix uses of non-empty transparent comparator in <map> (#152624)
The `__get_value()` member function was removed in LLVM 21, but the
calls in `<map>` weren't removed. This patch completes the removal and
adds regression test cases.

Fixes #152543.
2025-08-09 02:41:06 +08:00
Nikolas Klauser
6897ca460e
[libc++] Remove unnecessary friend declarations from <__tree> (#152133)
Removing the unnecessary friend declarations from `<__tree>` also
removes the need for forward declaration headers for `map` and `set`,
which this patch also removes.
2025-08-07 09:18:31 +02:00
Nikolas Klauser
1cac2be874
[libc++] Optimize copy construction and assignment of __tree (#151304)
```
----------------------------------------------------------------------------------------------------------
Benchmark                                                                              old             new
----------------------------------------------------------------------------------------------------------
std::map<int, int>::ctor(const&)/0                                                 15.5 ns         14.9 ns
std::map<int, int>::ctor(const&)/32                                                 474 ns          321 ns
std::map<int, int>::ctor(const&)/1024                                             24591 ns        11101 ns
std::map<int, int>::ctor(const&)/8192                                            236153 ns        98868 ns
std::map<std::string, int>::ctor(const&)/0                                         15.2 ns         14.9 ns
std::map<std::string, int>::ctor(const&)/32                                        2673 ns         2340 ns
std::map<std::string, int>::ctor(const&)/1024                                    115354 ns        86088 ns
std::map<std::string, int>::ctor(const&)/8192                                   1298510 ns       626876 ns
std::map<int, int>::operator=(const&) (into cleared Container)/0                   16.5 ns         16.1 ns
std::map<int, int>::operator=(const&) (into cleared Container)/32                   548 ns          323 ns
std::map<int, int>::operator=(const&) (into cleared Container)/1024               28418 ns        11026 ns
std::map<int, int>::operator=(const&) (into cleared Container)/8192              281827 ns        97113 ns
std::map<int, int>::operator=(const&) (into populated Container)/0                 2.42 ns         1.85 ns
std::map<int, int>::operator=(const&) (into populated Container)/32                 369 ns         73.0 ns
std::map<int, int>::operator=(const&) (into populated Container)/1024             24078 ns         2322 ns
std::map<int, int>::operator=(const&) (into populated Container)/8192            266537 ns        22963 ns
std::map<std::string, int>::operator=(const&) (into cleared Container)/0           16.6 ns         16.2 ns
std::map<std::string, int>::operator=(const&) (into cleared Container)/32          2614 ns         1622 ns
std::map<std::string, int>::operator=(const&) (into cleared Container)/1024      116826 ns        63281 ns
std::map<std::string, int>::operator=(const&) (into cleared Container)/8192     1316655 ns       649177 ns
std::map<std::string, int>::operator=(const&) (into populated Container)/0         2.42 ns         1.89 ns
std::map<std::string, int>::operator=(const&) (into populated Container)/32        1264 ns          581 ns
std::map<std::string, int>::operator=(const&) (into populated Container)/1024    238826 ns        39943 ns
std::map<std::string, int>::operator=(const&) (into populated Container)/8192   2412327 ns       379456 ns
```

Fixes #77658
Fixes #62571
2025-08-05 09:49:40 +02:00
Nikolas Klauser
afcf76bda1
[libc++] Fix insert() calling incorrect constructors (#146231)
This fixes `insert()` calling the wrong `allocator_traits::construct` in
the associative containers by removing the special handling that lead to
the inconsistencty inside `__tree` and `__hash_table`.
2025-07-10 09:24:15 +02:00
Nikolas Klauser
bdbac2bb49
[libc++] default some special members in map and set (#147081)
We don't actually do anything special in these special member functions,
so we can just `= default` them to save a bit of code.
2025-07-05 18:09:40 +02:00
Nikolas Klauser
be00098632
[libc++] Remove a bunch of now unnecessary indirections in __tree (#142397)
Most notably, this removes the notion of a distinct `value_type` and
`__container_value_type` from `__tree`, since these are now always the
same type. There are a few places we need to keep `__value_type` around,
since they are ABI visibile. In these cases `_Tp` is used directly. The
second simplification here is that we use `const value_type&` instead of
`const key_type&` in a few places and make use of the fact that the
comparator is capable of comparing any combination of `key_type` and
`value_type`.

This is a follow-up to #134819.
2025-06-23 10:47:47 +02:00
Hui
692c5cdb56
[libc++] Do not call reserve in flat containers if underlying container is user defined (#140379)
This is brought up in the LWG reflector. We currently call `reserve` if
the underlying container has one. But the spec does not specify what
`reserve` should do for Sequence Container. So in theory if the
underlying container is user defined type and it can have a function
called `reserve` which does something completely different.

The fix is to just call `reserve` for STL containers if it has one
2025-06-07 08:47:46 +01:00
Nikolas Klauser
a925e90ec2
[libc++][NFC] Remove some unused code from <map> (#142408) 2025-06-06 15:27:05 +02:00
Nikolas Klauser
962aa2666f
[libc++] Don't instantiate allocators in __tree on an incomplete type (#140225)
This causes a mismatch between `value_type` and
`allocator_type::value_type` in `__tree`, but I think that's acceptable.
`__tree` primarily gets a `__value_type` wrapper due to potential ABI
breaks and unwraps it to the same as `allocator_type::value_type` in the
end. A cleanup patch will also change `__tree::value_type` to be the
same as `allocator_type::value_type`, making the type mismatch only
visible where `__tree` is instantiated in `map`.
2025-05-18 12:38:06 +02:00
Christopher Di Bella
c41812e6ea
[libcxx] applies #134819 to insert_or_assign with const key_type& (#140124)
This was missed due to using prvalues in the test case, which were
picked up by the rvalue-reference overload instead.
2025-05-16 08:56:45 +02:00
Nikolas Klauser
53f11dd4d6
[libc++] Avoid type-punning between __value_type and pair (#134819)
Before this patch, we were dereferencing pointers to objects which were
never constructed. Now we always assume that nodes store `pair<const
KeyT, ValueT>` for maps instead, as they actually do. This patch also
allows for significant follow-up simplifications, since
`__node_value_type` and `__container_value_type` are the same type now.
2025-05-15 09:01:56 +02:00
Nikolas Klauser
af9c04fa68
[libc++] Remove _LIBCPP_TEMPLATE_VIS (#134885)
The need for `_LIBCPP_TEMPLATE_VIS` has been removed in #133233.
2025-04-09 23:47:57 +02:00
Mark de Wever
73cd84a90e
[NFC][libc++] Adds (multi|)(map|set) forward declarations. (#131541)
This removes duplicated forward declarations of these classes.

closes: #131518
2025-03-20 18:00:01 +01:00
Louis Dionne
5e26fb1699
[libc++] Qualify calls to nullary functions like __throw_foo (#122465)
This is technically not necessary in most cases to prevent issues with ADL,
but let's be consistent. This allows us to remove the libcpp-qualify-declval
clang-tidy check, which is now enforced by the robust-against-adl clang-tidy check.
2025-02-21 07:59:46 -05:00
Nikolas Klauser
b9a2658a3e
[libc++][C++03] Use __cxx03/ headers in C++03 mode (#109002)
This patch implements the forwarding to frozen C++03 headers as
discussed in
https://discourse.llvm.org/t/rfc-freezing-c-03-headers-in-libc. In the
RFC, we initially proposed selecting the right headers from the Clang
driver, however consensus seemed to steer towards handling this in the
library itself. This patch implements that direction.

At a high level, the changes basically amount to making each public
header look like this:

```
// inside <vector>
#ifdef _LIBCPP_CXX03_LANG
#  include <__cxx03/vector>
#else
  // normal <vector> content
#endif
```

In most cases, public headers are simple umbrella headers so there isn't
much code in the #else branch. In other cases, the #else branch contains
the actual implementation of the header.
2024-12-21 13:01:48 +01:00
Nikolas Klauser
59890c1334
[libc++] Granularize <new> includes (#119964) 2024-12-17 11:29:16 +01:00
Nikolas Klauser
c166a9c713
[libc++] Add #if 0 block to all the top-level headers (#119234)
Including The frozen C++03 headers results in a lot of formatting
changes in the main headers, so this splits these changes into a
separate commit instead.

This is part of
https://discourse.llvm.org/t/rfc-freezing-c-03-headers-in-libc.
2024-12-10 16:02:12 +01:00
Hui
8f9cce0bef
[libc++] Add container_traits (prework for std::flat_map) (#109578)
This PR is extracted from
https://github.com/llvm/llvm-project/pull/98643, as per code review
request
https://github.com/llvm/llvm-project/pull/98643#discussion_r1768967793
2024-10-12 18:29:59 +01:00
Louis Dionne
09e3a36058
[libc++][modules] Fix missing and incorrect includes (#108850)
This patch adds a large number of missing includes in the libc++ headers
and the test suite. Those were found as part of the effort to move
towards a mostly monolithic top-level std module.
2024-09-16 15:06:20 -04:00
Nikolas Klauser
17e0686ab1
[libc++][NFC] Use [[__nodiscard__]] unconditionally (#80454)
`__has_cpp_attribute(__nodiscard__)` is always true now, so we might as
well replace `_LIBCPP_NODISCARD`. It's one less macro that can result in
bad diagnostics.
2024-09-12 21:18:43 +02:00
Hristo Hristov
d043e4c322
[libc++] Restore __synth_three_way lambda (#90398)
Restore `__synth_three_way` lambda to match the Standard. 
GH-57222 is done, restoring the Standard wording implementation should
be possible.


df28d4412c/libcxx/include/__compare/synth_three_way.h (L28)

According to comment
https://github.com/llvm/llvm-project/issues/59513#issuecomment-2068338762,
GH-59513 is not a blocker.

Co-authored-by: Hristo Hristov <zingam@outlook.com>
2024-07-07 20:49:10 +03:00
Hui
79e8a59523
[libc++] Move allocator assertion into allocator_traits (#94750)
There is code duplication in all containers that static_assert the
allocator matches the allocator requirements in the spec. This check can
be moved into a more centralised place.
2024-06-25 10:13:48 -05:00
Nikolas Klauser
1f98ac095e
[libc++][NFC] Replace _NOEXCEPT and _LIBCPP_CONSTEXPR macros with the keywords in C++11 code (#96387) 2024-06-23 22:03:41 +02:00
Louis Dionne
e2c2ffbe7a
[libc++][NFC] Run clang-format on libcxx/include again (#95874)
As time went by, a few files have become mis-formatted w.r.t.
clang-format. This was made worse by the fact that formatting was not
being enforced in extensionless headers. This commit simply brings all
of libcxx/include in-line with clang-format again.

We might have to do this from time to time as we update our clang-format
version, but frankly this is really low effort now that we've formatted
everything once.
2024-06-18 09:13:45 -04:00
Nikolas Klauser
cb41740187
[libc++] Refactor<__type_traits/is_swappable.h> (#86822)
This changes the `is_swappable` implementation to use variable templates
first and basing the class templates on that. This avoids instantiating
them when the `_v` versions are used, which are generally less resource
intensive.
2024-06-18 11:01:43 +02:00
Nikolas Klauser
bbe4a80605
[libc++] Enable modernize-use-equals-delete (#93293)
Differential Revision: https://reviews.llvm.org/D121213
2024-06-18 10:51:57 +02:00
Nikolas Klauser
6b4b29f859
[libc++][NFC] Remove unnecessary parens in static_asserts (#95605)
These were required a long time ago due to `static_assert` not actually
being available in C++03. Now `static_assert` is simply mapped to
`_Static_assert` in C++03, making the additional parens unnecessary.
2024-06-18 10:45:30 +02:00
Louis Dionne
04f01a2b9c
[libc++] Make the __availability header a sub-header of __config (#93083)
In essence, this header has always been related to configuration of
the library but we didn't want to put it inside <__config> due to
complexity reasons. Now that we have sub-headers in <__config>, we
can move <__availability> to it and stop including it everywhere since
we already obtain the required macros via <__config>.
2024-05-28 18:29:11 -07:00
Nikolas Klauser
3aba4b5b4f
[libc++][NFC] Refactor __is_transparent to be a variable template (#90865) 2024-05-08 10:34:55 +02:00
Nikolas Klauser
83bc7b5771
[libc++] Remove _LIBCPP_DISABLE_NODISCARD_EXTENSIONS and refactor the tests (#87094)
This also adds a few tests that were missing.
2024-04-22 22:13:58 +02:00
Louis Dionne
37dca605c9
[libc++] Clean up includes of <__assert> (#80091)
Originally, we used __libcpp_verbose_abort to handle assertion failures.
That function was declared from all public headers. Since we don't use
that mechanism anymore, we don't need to declare __libcpp_verbose_abort
from all public headers, and we can clean up a lot of unnecessary
includes.

This patch also moves the definition of the various assertion categories
to the <__assert> header, since we now rely on regular IWYU for these
assertion macros.

rdar://105510916
2024-02-29 10:12:22 -05:00
Nikolas Klauser
76a2472715
[libc++] Refactor more __enable_ifs to the canonical style (#81457)
This brings the code base closer to having only a single style of
`enable_if`s.
2024-02-20 01:47:38 +01:00
Louis Dionne
7b4622514d
[libc++] Fix missing and incorrect push/pop macros (#79204)
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
2024-01-25 15:48:46 -05:00
Louis Dionne
5b57da32a8 [libc++] Fix nolint comment that became useless after running clang-format 2023-12-18 17:49:21 -05:00
Louis Dionne
9783f28cbb
[libc++] Format the code base (#74334)
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
2023-12-18 14:01:33 -05:00
Louis Dionne
77a00c0d54
[libc++] Replace uses of _VSTD:: by std:: (#74331)
As part of the upcoming clang-formatting of libc++, this patch performs
the long desired removal of the _VSTD macro.

See https://discourse.llvm.org/t/rfc-clang-formatting-all-of-libc-once-and-for-all
for the clang-format proposal.
2023-12-05 11:19:15 -05:00
Louis Dionne
4c19854222
[libc++] Rename _LIBCPP_INLINE_VISIBILITY to _LIBCPP_HIDE_FROM_ABI (#74095)
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.
2023-12-04 10:25:14 -05:00
Mark de Wever
7cc72a0a2e Implement syncstream (p0053)
This patch implements `std::basic_syncbuf` and `std::basic_osyncstream` as specified in paper p0053r7. ~~For ease of reviewing I am submitting this patch before submitting a patch for `std::basic_osyncstream`. ~~

~~Please note, this patch is not 100% complete. I plan on adding more tests (see comments), specifically I plan on adding tests for multithreading and synchronization.~~

Edit: I decided that it would be far easier for me to keep track of this and make changes that affect both `std::basic_syncbuf` and `std::basic_osyncstream` if both were in one patch.

The patch was originally written by @zoecarver

Implements
- P0053R7 - C++ Synchronized Buffered Ostream
- LWG-3127 basic_osyncstream::rdbuf needs a const_cast
- LWG-3334 basic_osyncstream move assignment and destruction calls basic_syncbuf::emit() twice
- LWG-3570 basic_osyncstream::emit should be an unformatted output function
- LWG-3867 Should std::basic_osyncstream's move assignment operator be noexcept?

Reviewed By: ldionne, #libc

Differential Revision: https://reviews.llvm.org/D67086
2023-11-08 17:45:06 +01:00
philnik777
a65070a76a
[libc++] Remove a few transitive includes (#70553) 2023-10-29 18:31:37 +01:00
Nikolas Klauser
9f3e3efd98 [libc++][NFC] Refactor __enable_if return types to defaulted template parameters
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/D157787
2023-09-01 17:52:31 -07:00
varconst
4122db1fbd [libc++][hardening] Categorize most assertions inside the container classes.
This introduces:
- `_LIBCPP_ASSERT_VALID_INPUT_RANGE`;
- `_LIBCPP_ASSERT_VALID_CONTAINER_ACCESS`;
- `_LIBCPP_ASSERT_VALID_ITERATOR_ACCESS`;
- `_LIBCPP_ASSERT_VALID_ALLOCATOR`;
- `_LIBCPP_ASSERT_INTERNAL`.

Differential Revision: https://reviews.llvm.org/D155349
2023-07-20 10:14:43 -07:00
varconst
ef70fe4d26 [libc++][ranges] Implement the changes to node-based containers from P1206 (ranges::to):
- add the `from_range_t` constructors and the related deduction guides;
- add the `insert_range`/`assign_range`/etc. member functions.

(Note: this patch is split from https://reviews.llvm.org/D142335)

Differential Revision: https://reviews.llvm.org/D149830
2023-07-18 11:01:10 -07:00
varconst
cd0ad4216c [libc++][hardening][NFC] Introduce _LIBCPP_ASSERT_UNCATEGORIZED.
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
2023-06-28 15:10:31 -07:00
Louis Dionne
2da049a141 [libc++] Add incomplete availability markup for std::pmr
This fixes rdar://110330781, which asked for the feature-test macro
for std::pmr to take into account the deployment target. It doesn't
fix https://llvm.org/PR62212, though, because the availability markup
itself must be disabled until some Clang bugs have been fixed.

This is pretty vexing, however at least everything should work once
those Clang bugs have been fixed. In the meantime, this patch at least
adds the required markup (as disabled) and ensures that the feature-test
macro for std::pmr is aware of the deployment target requirement.

Differential Revision: https://reviews.llvm.org/D135813
2023-06-20 10:59:05 -04:00
Hristo Hristov
cc2d061266 [libc++][spaceship][NFC] Improved consistency - removed inline specifier for operator<=>
Removed `inline` specifier for consistency as discussed in D148416 previously.

Reviewed By: #libc, Mordante

Differential Revision: https://reviews.llvm.org/D151248
2023-05-25 10:20:18 +03:00
Nikolas Klauser
80643d9366 [libc++][NFC] Rename iterator category checks to make it obvious that they check //only// the iterator category
We plan to add concepts for checking that iterators actually provide what they claim to. This is to avoid people thinking that these type traits actually check the iterator requirements in more detail.

Reviewed By: ldionne, #libc

Spies: Mordante, libcxx-commits, wenlei

Differential Revision: https://reviews.llvm.org/D150801
2023-05-18 15:37:28 -07:00
Nikolas Klauser
83ce139721 [libc++] Add hide_from_abi check for classes
We already have a clang-tidy check for making sure that `_LIBCPP_HIDE_FROM_ABI` is on free functions. This patch extends this to class members. The places where we don't check for `_LIBCPP_HIDE_FROM_ABI` are classes for which we have an instantiation in the library.

Reviewed By: ldionne, Mordante, #libc

Spies: jplehr, mikhail.ramalho, sstefan1, libcxx-commits, krytarowski, miyuki, smeenai

Differential Revision: https://reviews.llvm.org/D142332
2023-04-16 15:23:23 +02:00
Nikolas Klauser
75196f8e72 [libc++] Remove <cstdlib> includes
We changed the `abort` calls when trying to throw exceptions in `-fno-exceptions` mode to `__verbose_abort` calls, which removes the dependency in most files.

Reviewed By: ldionne, #libc

Spies: dim, emaste, mikhail.ramalho, smeenai, libcxx-commits

Differential Revision: https://reviews.llvm.org/D146076
2023-04-09 02:52:33 +02:00
Mark de Wever
9c0efc8a03 [libc++] Module fixes for __synth_three_way.
These changes make it possible to use __synth_three_way in modules. The
change from a lambda to a function is a Clang issue.

The change is list was needed since the compiler couldn't deduce the
comparison template argument.

Adds a few missing includes too.

Reviewed By: #libc, ldionne

Differential Revision: https://reviews.llvm.org/D146545
2023-04-07 18:54:09 +02:00