In LLVM 19 removed the extension with an opt-in macro. This finally
removes that option too and removes a few `const_cast`s where I know
that they exist only to support this extension.
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
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
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
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
Other macros that disable parts of the library are named `_LIBCPP_HAS_NO_WHATEVER`.
Reviewed By: ldionne, Mordante, #libc
Spies: libcxx-commits, smeenai
Differential Revision: https://reviews.llvm.org/D143163
This change is almost fully mechanical. The only interesting change is in `generate_feature_test_macro_components.py` to generate `_LIBCPP_STD_VER >=` instead. To avoid churn in the git-blame this commit should be added to the `.git-blame-ignore-revs` once committed.
Reviewed By: ldionne, var-const, #libc
Spies: jloser, libcxx-commits, arichardson, arphaman, wenlei
Differential Revision: https://reviews.llvm.org/D143962
Having an ODR violation with `__exception_guard` seems to be problematic in LTO builds. To avoid the ODR violation, give the class different names for exception/no-exceptions mode and have an alias to the correct class.
Reviewed By: ldionne, #libc, alexfh
Spies: aeubanks, dblaikie, joanahalili, alexfh, rupprecht, libcxx-commits
Differential Revision: https://reviews.llvm.org/D143071
__exception_guard is a no-op in -fno-exceptions mode to produce better code-gen. This means that we don't provide the strong exception guarantees. However, Clang doesn't generate cleanup code with exceptions disabled, so even if we wanted to provide the strong exception guarantees we couldn't. This is also only relevant for constructs with a stack of -fexceptions > -fno-exceptions > -fexceptions code, since the exception can't be caught where exceptions are disabled. While -fexceptions > -fno-exceptions is quite common (e.g. libc++.dylib > -fno-exceptions), having another layer with exceptions enabled seems a lot less common, especially one that tries to catch an exception through -fno-exceptions code.
Fixes https://github.com/llvm/llvm-project/issues/56783
Reviewed By: ldionne, Mordante, huixie90, #libc
Spies: EricWF, alexfh, hans, joanahalili, libcxx-commits
Differential Revision: https://reviews.llvm.org/D133661
This was discussed on Discord with the consensus that we should rename the macros.
Reviewed By: ldionne, Mordante, var-const, avogelsgesang, jloser, #libc
Spies: libcxx-commits
Differential Revision: https://reviews.llvm.org/D131498
This mostly copys the `<experimental/functional>` stuff and updates the code to current libc++ style.
Reviewed By: ldionne, #libc
Spies: nlopes, adamdebreceni, arichardson, libcxx-commits, mgorny
Differential Revision: https://reviews.llvm.org/D121074
This patch implements P0674R1, i.e. support for arrays in std::make_shared
and std::allocate_shared.
Co-authored-by: Zoe Carver <z.zoelec2@gmail.com>
Differential Revision: https://reviews.llvm.org/D62641
This commit reverts 5aaefa51 (and also partly 7f285f48e77 and b6d75682f9,
which were related to the original commit). As landed, 5aaefa51 had
unintended consequences on some downstream bots and didn't have proper
coverage upstream due to a few subtle things. Implementing this is
something we should do in libc++, however we'll first need to address
a few issues listed in https://reviews.llvm.org/D106124#3349710.
Differential Revision: https://reviews.llvm.org/D120683
libc++ has started splicing standard library headers into much more
fine-grained content for maintainability. It's very likely that outdated
and naive tooling (some of which is outside of LLVM's scope) will
suggest users include things such as <__ranges/access.h> instead of
<ranges>, and Hyrum's law suggests that users will eventually begin to
rely on this without the help of tooling. As such, this commit
intends to protect users from themselves, by making it a hard error for
anyone outside of the standard library to include libc++ detail headers.
Differential Revision: https://reviews.llvm.org/D106124
Basically a rebase of D104980; most of that patch had already happened
via gradual drive-by changes, but this finishes it up.
Don't touch the inclusions from `<__functional_base>`, `<__hash_table>`,
or `<__locale>`; those could be removed if we propagated the
inclusions up to the includers of those files, but there are lots
of those includers.
`<algorithm>`, `<functional>`, and `<memory>` already include `<utility>`
at the top level. `<iterator>` did not, so I've added it there.
Differential Revision: https://reviews.llvm.org/D119020
Also:
- refactor out `__voidify`;
- use the `destroy` algorithm internally;
- refactor out helper classes used in tests for `uninitialized_*`
algorithms.
Differential Revision: https://reviews.llvm.org/D115626
Defined in [`specialized.algorithms`](wg21.link/specialized.algorithms).
Also:
- refactor the existing non-range implementation so that most of it
can be shared between the range-based and non-range-based algorithms;
- remove an existing test for the non-range version of
`uninitialized_default_construct{,_n}` that likely triggered undefined
behavior (it read the values of built-ins after default-initializing
them, essentially reading uninitialized memory).
Reviewed By: #libc, Quuxplusone, ldionne
Differential Revision: https://reviews.llvm.org/D115315
Detected by evil-izing the widely used `MoveOnly` testing type.
I had to patch some tests that were themselves using its comma operator,
but I think that's a worthwhile cost in order to catch more places
in our headers that needed comma-proofing.
The trick here is that even `++ptr, SomeClass()` can find a comma operator
by ADL, if `ptr` is of type `Evil*`. (A comma between two operands
of non-class-or-enum type is always treated as the built-in
comma, without ADL. But if either operand is class-or-enum, then
ADL happens for _both_ operands' types.)
Differential Revision: https://reviews.llvm.org/D109414
Also, improve tests for std::destroy and std::destroy_n so that they
check for array support.
These changes are part of http://wg21.link/p0896 (the One Ranges proposal).
Differential Revision: https://reviews.llvm.org/D106916