Currently, the library-internal feature test macros are only defined if
the feature is not available, and always have the prefix
`_LIBCPP_HAS_NO_`. This patch changes that, so that they are always
defined and have the prefix `_LIBCPP_HAS_` instead. This changes the
canonical use of these macros to `#if _LIBCPP_HAS_FEATURE`, which means
that using an undefined macro (e.g. due to a missing include) is
diagnosed now. While this is rather unlikely currently, a similar change
in `<__configuration/availability.h>` caught a few bugs. This also
improves readability, since it removes the double-negation of `#ifndef
_LIBCPP_HAS_NO_FEATURE`.
The current patch only touches the macros defined in `<__config>`. If
people are happy with this approach, I'll make a follow-up PR to also
change the macros defined in `<__config_site>`.
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.
This ABI break only affects fancy pointer which have a different value
representation when pointing to a base of T instead of T itself. This
seems like a rather small set of fancy pointers, which themselves
already represent a very small niche. This patch swaps a pointer to T
with a pointer to base of T in a few library-internal types.
This significantly simplifies the code, improves compile times and
improves the object layout of types using `__compressed_pair` in the
unstable ABI. The only downside is that this is extremely ABI sensitive
and pedantically breaks the ABI for empty final types, since the address
of the subobject may change. The ABI of the whole object should not be
affected.
Fixes#91266Fixes#93069
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.
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.
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.
These are simply null checks, so use `_LIBCPP_ASSERT_NON_NULL`. This
allows us to restore a bunch of the old debug tests. I've extended them
to also cover the const iterators, as those run through different
codepaths than the const ones.
This does the easier (and less important) half of #80212.
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.
Also introduce `_LIBCPP_ASSERT_PEDANTIC` for assertions violating which
results in a no-op or other benign behavior, but which may nevertheless
indicate a bug in the invoking code.
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 patch removes undefined behavior in list and forward_list and __hash_table
caused by improperly beginning and ending the lifetime of the various node
classes. It allows removing the _LIBCPP_STANDALONE_DEBUG macro from
these node types since we now properly begin and end their lifetime,
meaning that we won't trip up constructor homing.
See https://reviews.llvm.org/D98750 for more information on what prompted
this patch.
This commit re-applies 0687e4d9f310, which had been reverted in b935882bdce7
because it broke the LLDB build. LLDB folks tell me I can go ahead and
re-commit this now.
Differential Revision: https://reviews.llvm.org/D101206
Co-authored-by: Amy Kwan <amy.kwan1@ibm.com>
This patch removes undefined behavior in list and forward_list and __hash_table
caused by improperly beginning and ending the lifetime of the various node
classes. It allows removing the _LIBCPP_STANDALONE_DEBUG macro from
these node types since we now properly begin and end their lifetime,
meaning that we won't trip up constructor homing.
See https://reviews.llvm.org/D98750 for more information on what prompted
this patch.
Differential Revision: https://reviews.llvm.org/D101206
Co-authored-by: Amy Kwan <amy.kwan1@ibm.com>
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
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
These macros are always defined identically, so we can simplify the code a bit by merging them.
Reviewed By: ldionne, #libc
Spies: libcxx-commits, krytarowski, smeenai
Differential Revision: https://reviews.llvm.org/D152652
Several headers are missing includes for things they use.
type_traits.is_enum needs to export type_traits.integral_constant so that clients can access its `value` member without explicitly including __type_traits/integral_constant.h themselves.
Make `subrange_fwd` a peer submodule to `subrange` rather than a submodule of it, and have `subrange` export `subrange_fwd`. That will make it easier to programmatically generate modules for the private detail headers, and it will accomplish the same effect that __ranges/subrange.h will make subrange_kind visible.
Reviewed By: Mordante, #libc
Differential Revision: https://reviews.llvm.org/D150055
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
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
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
As of now containers key_eq might get called when rehashing happens, which is redundant for unique keys containers.
Reviewed By: #libc, philnik, Mordante
Differential Revision: https://reviews.llvm.org/D128021
The debug mode has been broken pretty much ever since it was shipped
because it was possible to enable the debug mode in user code without
actually enabling it in the dylib, leading to ODR violations that
caused various kinds of failures.
This commit makes the debug mode a knob that is configured when
building the library and which can't be changed afterwards. This is
less flexible for users, however it will actually work as intended
and it will allow us, in the future, to add various kinds of checks
that do not assume the same ABI as the normal library. Furthermore,
this will make the debug mode more robust, which means that vendors
might be more tempted to support it properly, which hasn't been the
case with the current debug mode.
This patch shouldn't break any user code, except folks who are building
against a library that doesn't have the debug mode enabled and who try
to enable the debug mode in their code. Such users will get a compile-time
error explaining that this configuration isn't supported anymore.
In the future, we should further increase the granularity of the debug
mode checks so that we can cherry-pick which checks to enable, like we
do for unspecified behavior randomization.
Differential Revision: https://reviews.llvm.org/D122941
Instead of providing two different constructors for iterators that
support the debug mode, provide a single constructor but leave the
container parameter unused when the debug mode is not enabled.
This allows simplifying all the call sites to unconditionally pass
the container, which removes a bunch of duplication in the container's
implementation.
Note that this patch does add some complexity to std::span, however
that is only because std::span has the ability to use raw pointers
as iterators instead of __wrap_iter. In retrospect, I believe it was
a mistake to provide that capability, and so it will be removed in a
future patch, along with the complexity added by this patch.
Differential Revision: https://reviews.llvm.org/D126993
