libc++ no longer supports C++11 compilers that don't implement `= default`.
This patch removes all instances of the feature test macro
_LIBCPP_HAS_NO_DEFAULTED_FUNCTIONS as well as the potentially dead code it hides.
llvm-svn: 287321
This is a generalization of `_LIBCPP_NEW_DELETE_VIS`; the new macro name
captures the semantics better, and also allows us to get rid of the
`_WIN32` check in `include/new`. No functional change.
Differential Revision: https://reviews.llvm.org/D26702
llvm-svn: 287164
Create this define in __config and use it elsewhere, instead of checking
the operating system/library defines in other files. The aim is to
reduce the usage of _WIN32 outside __config. No functional change.
Differential Revision: https://reviews.llvm.org/D25741
llvm-svn: 285582
This prevent the symbols from being both externally available and hidden, which
causes them to be linked incorrectly. This is only a problem when the address
of the function is explicitly taken since it will always be inlined otherwise.
This patch fixes the issues that caused r285456 to be reverted, and can
now be reapplied.
llvm-svn: 285531
This patch does two seperate things. First it adds a file called
"__libcpp_version" which only contains the current libc++ version
(currently 4000). This file is not intended for use as a header. This file
is used by Clang in order to easily determine the installed libc++ version.
This allows Clang to enable/disable certain language features only when the
library supports them.
The second change is the addition of _LIBCPP_LIBRARY_VERSION macro, which
returns the version of the installed dylib since it may be different than
the headers.
llvm-svn: 285382
Summary:
Adapt implementation of Library Fundamentals TS optional into an implementation of N4606 optional.
- Update relational operators per http://wg21.link/P0307
- Update to requirements of http://wg21.link/P0032
- Extension: Implement trivial copy/move construction/assignment for `optional<T>` when `T` is trivially copyable.
Audit P/Rs for optional LWG issues:
- 2756 "C++ WP optional<T> should 'forward' T's implicit conversions" Implemented, which also resolves 2753 "Optional's constructors and assignments need constraints" (modulo my refusal to explicitly delete the move operations, which is a design error that I'm working on correcting in the 2756 P/R).
- 2736 "nullopt_t insufficiently constrained" Already conforming. I've added a test ensuring that `nullopt_t` is not copy-initializable from an empty braced-init-list, which I believe is the root intent of the issue, to avoid regression.
- 2740 "constexpr optional<T>::operator->" Already conforming.
- 2746 "Inconsistency between requirements for emplace between optional and variant" No P/R, but note that the author's '"suggested resolution" is already implemented.
- 2748 "swappable traits for optionals" Already conforming.
- 2753 "Optional's constructors and assignments need constraints" Implemented.
Most of the work for this patch was done by Casey Carter @ Microsoft. Thank you Casey!
Reviewers: mclow.lists, CaseyCarter, EricWF
Differential Revision: https://reviews.llvm.org/D22741
llvm-svn: 283980
This patch is largely thanks to Casey Carter @ Microsoft. He did the initial
work of porting our experimental implementation and tests over to namespace
std.
llvm-svn: 283977
Fuchsia is a new operating system which uses musl as the standard
C library, libc++ and libc++abi as the C++ standard library.
Differential Revision: https://reviews.llvm.org/D25414
llvm-svn: 283788
This was caused by r281673, specifically changing `_LIBCPP_EXTERN_TEMPLATE_TYPE_VIS`
from `__attribute__((__type_visibility__("default")))` to
`__attribute__((__visibility("default")))`.
I made that change because I thought the external instantiations needed
their members to have default visibility. However since libc++ never builds
with -fvisibility=hidden this appears not to be needed. Instead this change
caused previously hidden inline methods to become un-hidden, which is a regression.
This patch reverts the problematic change and fixes PR30642.
llvm-svn: 283620
Summary:
The current implementation of `hash_code()` for uniqued RTTI strings violates strict aliasing by dereferencing a type-punned pointer. Specifically it generates a `const char**` pointer from the address of the `__name` member before casting it to `const size_t*` and dereferencing it to get the hash. This is really just a complex and incorrect way of writing `reinterpret_cast<size_t>(__name)`.
This patch changes the conversion sequence so that it no longer contains UB.
Reviewers: howard.hinnant, mclow.lists
Subscribers: rjmccall, cfe-commits
Differential Revision: https://reviews.llvm.org/D24012
llvm-svn: 283408
builds.
On Windows the __declspec(dllimport) and __declspec(dllexport) attributes
require linking to a DLL, not a static library. Previously these annotations
were disabled by default unless _LIBCPP_DLL was defined. However the DLL
configuration is probably the more common one, so it should be supported by
default.
This patch enables import/export attributes by default and adds a
_LIBCPP_DISABLE_DLL_IMPORT_EXPORT macro which can be used to disable this
behavior. If libc++ is built as a static library on Windows then a custom __config
header will be generated that predefines this macro.
This patch is based off work by Shoaib Meenai.
llvm-svn: 282449
Summary:
Libc++ still uses per-feature configuration macros when configuring for C++11. However libc++ requires a feature-complete C++11 compiler so there is no reason to check individual features. This patch starts the process of removing the feature specific macros and replacing their usage with `_LIBCPP_CXX03_LANG`.
This patch removes the __config macros:
* _LIBCPP_HAS_NO_TRAILING_RETURN
* _LIBCPP_HAS_NO_TEMPLATE_ALIASES
* _LIBCPP_HAS_NO_ADVANCED_SFINAE
* _LIBCPP_HAS_NO_DEFAULT_FUNCTION_TEMPLATE_ARGS
* _LIBCPP_HAS_NO_STATIC_ASSERT
As a drive I also changed our C++03 static_assert to use _Static_assert if available.
I plan to commit this without review if nobody voices an objection.
Reviewers: mclow.lists
Subscribers: cfe-commits
Differential Revision: https://reviews.llvm.org/D24895
llvm-svn: 282347
Summary:
This patch has been a long time coming (Thanks @eugenis). It changes `_LIBCPP_INLINE_VISIBILITY` to use `__attribute__((internal_linkage))` instead of `__attribute__((visibility("hidden"), always_inline))`.
The point of `_LIBCPP_INLINE_VISIBILITY` is to prevent inline functions from being exported from both the libc++ library and from user libraries. This helps libc++ better manage it's ABI.
Previously this was done by forcing inlining and modifying the symbols visibility. However inlining isn't guaranteed and symbol visibility only affects shared libraries making this an imperfect solution. `internal_linkage` improves this situation by making all symbols local to the TU they are emitted in, regardless of inlining or visibility. IIRC the effect of applying `__attribute__((internal_linkage))` to an inline function is the same as applying `static`.
For more information about the attribute see: http://lists.llvm.org/pipermail/cfe-dev/2015-October/045580.html
Most of the work for this patch was done by @eugenis.
Reviewers: mclow.lists, eugenis
Subscribers: eugenis, cfe-commits
Differential Revision: https://reviews.llvm.org/D24642
llvm-svn: 282345
On Windows, marking an `extern template class` declaration as exported
actually forces an instantiation, which is not the desired behavior.
Instead, the actual explicit instantiations need to be exported.
Differential Revision: https://reviews.llvm.org/D24679
llvm-svn: 281925
Summary:
None of these checks are specific to Android devices. If libc++ was
used with Bionic on a normal Linux system these checks would still be
needed.
Reviewers: mclow.lists, EricWF
Subscribers: compnerd, tberghammer, danalbert, srhines, cfe-commits
Differential Revision: https://reviews.llvm.org/D24690
llvm-svn: 281921
gcc and clang in gcc compatibility mode do not accept __forceinline. Use
the gcc attribute for them instead.
Differential Revision: https://reviews.llvm.org/D24678
llvm-svn: 281766
Summary:
This patch fixes a number of problems with the visibility macros across GCC (on Unix) and Windows (DLL import/export semantics). All of the visibility macros are now documented under `DesignDocs/VisibilityMacros.rst`. Now I'll no longer forget the subtleties of each!
This patch adds two new visibility macros:
* `_LIBCPP_ENUM_VIS` for controlling the typeinfo of enum types. Only Clang supports this.
* `_LIBCPP_EXTERN_TEMPLATE_TYPE_VIS` for redefining visibility on explicit instantiation declarations. Clang and Windows require this.
After applying this patch GCC only emits one -Wattribute warning opposed to 30+.
Reviewers: mclow.lists, EricWF
Subscribers: beanz, mgorny, cfe-commits
Differential Revision: https://reviews.llvm.org/D24602
llvm-svn: 281673
An enum class has associated type info. In the Microsoft ABI, type info
is emitted in the COMDAT section and isn't exported, so clang rightfully
complains about __declspec(dllexport) being unused for an enum class.
On other platforms, we still want to export the type info.
Differential Revision: https://reviews.llvm.org/D24065
llvm-svn: 281264
This patch further decouples libc++ from pthread, allowing libc++ to be built
against other threading systems. There are two main use cases:
- Building libc++ against a thread library other than pthreads.
- Building libc++ with an "external" thread API, allowing a separate library to
provide the implementation of that API.
The two use cases are quite similar, the second one being sligtly more
de-coupled than the first. The cmake option LIBCXX_HAS_EXTERNAL_THREAD_API
enables both kinds of builds. One needs to place an <__external_threading>
header file containing an implementation of the "libc++ thread API" declared
in the <__threading_support> header.
For the second use case, the implementation of the libc++ thread API can
delegate to a custom "external" thread API where the implementation of this
external API is provided in a seperate library. This mechanism allows toolchain
vendors to distribute a build of libc++ with a custom thread-porting-layer API
(which is the "external" API above), platform vendors (recipients of the
toolchain/libc++) are then required to provide their implementation of this API
to be linked with (end-user) C++ programs.
Note that the second use case still requires establishing the basic types that
get passed between the external thread library and the libc++ library
(e.g. __libcpp_mutex_t). These cannot be opaque pointer types (libc++ sources
won't compile otherwise). It should also be noted that the second use case can
have a slight performance penalty; as all the thread constructs need to cross a
library boundary through an additional function call.
When the header <__external_threading> is omitted, libc++ is built with the
"libc++ thread API" (declared in <__threading_support>) as the "external" thread
API (basic types are pthread based). An implementation (pthread based) of this
API is provided in test/support/external_threads.cpp, which is built into a
separate DSO and linked in when running the libc++ test suite. A test run
therefore demonstrates the second use case (less the intermediate custom API).
Differential revision: https://reviews.llvm.org/D21968
Reviewers: bcraig, compnerd, EricWF, mclow.lists
llvm-svn: 281179
Summary:
Currently a number of GCC warnings are emitted when building libc++. This patch fixes or ignores all of them. The primary changes are:
* Work around strict aliasing issues in `typeinfo::hash_code()` by using __attribute__((may_alias)). However I think a non-aliasing `hash_code()` implementation is possible. Further investigation needed.
* Add `_LIBCPP_UNREACHABLE()` to switch in `strstream.cpp` to avoid -Wpotentially-uninitialized.
* Fix -Wunused-value warning in `__all` by adding a void cast.
* Ignore -Wattributes for now. There are a number of real attribute issues when using GCC but enabling the warning is too noisy.
* Ignore -Wliteral-suffix since it warns about the use of reserved identifiers. Note Only GCC 7.0 supports disabling this warning.
* Ignore -Wc++14-compat since it warns about the sized new/delete overloads.
Reviewers: EricWF
Differential Revision: https://reviews.llvm.org/D24003
llvm-svn: 280007
Summary:
This patch attempts to fix the undefined behavior in __hash_table by changing the node pointer types used throughout. The pointer types are changed for raw pointers in the current ABI and for fancy pointers in ABI V2 (since the fancy pointer types may not be ABI compatible).
The UB in `__hash_table` arises because tree downcasts the embedded end node and then deferences that pointer. Currently there are 2 node types in __hash_table:
* `__hash_node_base` which contains the `__next_` pointer.
* `__hash_node` which contains `__hash_` and `__value_`.
Currently the bucket list, iterators, and `__next_` pointers store pointers to `__hash_node` even though they all need to store `__hash_node_base` pointers.
This patch makes that change by introducing a `__next_pointer` typedef which is a pointer to `__hash_node` in the current ABI and `__hash_node_base` afterwards.
One notable change is to the type of `__bucket_list` which used to be defined as `unique_ptr<__node_pointer[], ...>` and is now `unique_ptr<__next_pointer[], ...>` meaning that we now allocate and deallocate different types using a different allocator. I'm going to give this part of the change more thought since it may introduce compatibility issues.
This change is similar to D20786.
Reviewers: mclow.lists, EricWF
Subscribers: cfe-commits
Differential Revision: https://reviews.llvm.org/D20787
llvm-svn: 276533
Summary:
This patch attempts to fix the undefined behavior in __tree by changing the node pointer types used throughout. The pointer types are changed for raw pointers in the current ABI and for fancy pointers in ABI V2 (since the fancy pointer types may not be ABI compatible).
The UB in `__tree` arises because tree downcasts the embedded end node and then deferences that pointer. Currently there are 3 node types in __tree.
* `__tree_end_node` which contains the `__left_` pointer. This node is embedded within the container.
* `__tree_node_base` which contains `__right_`, `__parent_` and `__is_black`. This node is used throughout the tree rebalancing algorithms.
* `__tree_node` which contains `__value_`.
Currently `__tree` stores the start of the tree, `__begin_node_`, as a pointer to a `__tree_node`. Additionally the iterators store their position as a pointer to a `__tree_node`. In both of these cases the pointee can be the end node. This is fixed by changing them to store `__tree_end_node` pointers instead.
To make this change I introduced an `__iter_pointer` typedef which is defined to be a pointer to either `__tree_end_node` in the new ABI or `__tree_node` in the current one.
Both `__tree::__begin_node_` and iterator pointers are now stored as `__iter_pointers`.
The other situation where `__tree_end_node` is stored as the wrong type is in `__tree_node_base::__parent_`. Currently `__left_`, `__right_`, and `__parent_` are all `__tree_node_base` pointers. Since the end node will only be stored in `__parent_` the fix is to change `__parent_` to be a pointer to `__tree_end_node`.
To make this change I introduced a `__parent_pointer` typedef which is defined to be a pointer to either `__tree_end_node` in the new ABI or `__tree_node_base` in the current one.
Note that in the new ABI `__iter_pointer` and `__parent_pointer` are the same type (but not in the old one). The confusion between these two types is unfortunate but it was the best solution I could come up with that maintains the ABI.
The typedef changes force a ton of explicit type casts to correct pointer types and to make current code compatible with both the old and new pointer typedefs. This is the bulk of the change and it's really messy. Unfortunately I don't know how to avoid it.
Please let me know what you think.
Reviewers: howard.hinnant, mclow.lists
Subscribers: howard.hinnant, bbannier, cfe-commits
Differential Revision: https://reviews.llvm.org/D20786
llvm-svn: 276003
This patch does the following:
* It renames `_LIBCPP_TRIVIAL_PAIR_COPY_CTOR` to `_LIBCPP_DEPRECATED_ABI_DISABLE_PAIR_TRIVIAL_COPY_CTOR`.
* It automatically enables this option on FreeBSD in ABI V1, since that's the current ABI FreeBSD ships.
* It cleans up the handling of this option in `std::pair`.
I would like the sign off from the FreeBSD maintainers. They will no longer need to keep their `__config` changes downstream.
I'm still hoping to come up with a better way to maintain the ABI without needing these constructors.
Reviewed in https://reviews.llvm.org/D21329
llvm-svn: 275749
This patch adds the weak_type typedef in shared_ptr. It is available in
C++17 and newer.
This patch also updates the _LIBCPP_STD_VER and TEST_STD_VER macros to
have the value of 16, since 2016 is the current year.
llvm-svn: 273839
Summary:
This patch implements the variadic `lock_guard` paper.
Making `lock_guard` variadic is a ABI breaking change because the specialization `lock_guard<_Mutex>` mangles differently then when it was the primary template. This change only provides variadic `lock_guard` in ABI V2 or when `_LIBCPP_ABI_VARIADIC_LOCK_GUARD` is defined.
Note that in ABI V2 `lock_guard` must always be declared as a variadic template, even in C++03, in order to keep the ABI consistent. For this reason `lock_guard` is forward declared as a variadic template in all standard dialects and therefore depends on variadic templates being provided as an extension in C++03. All supported versions of Clang and GCC provide this extension.
Reviewers: mclow.lists
Subscribers: K-ballo, mclow.lists, cfe-commits
Differential Revision: http://reviews.llvm.org/D21260
llvm-svn: 272634
The existing pthread detection code in __config is pretty good for
common operating systems. It doesn't allow cmake-time choices to be
made for uncommon operating systems though.
This change adds the LIBCXX_HAS_PTHREAD_API cmake flag, which turns
into the _LIBCPP_HAS_THREAD_API_PTHREAD preprocessor define. This is
a name change from the old _LIBCPP_THREAD_API_PTHREAD. The lit tests
want __config_site.in variables to have a _LIBCPP_HAS prefix.
http://reviews.llvm.org/D20573
llvm-svn: 270735
This patch extracts out all the pthread dependencies of libcxx into the
new header __threading_support. The motivation is to make it easy to
re-target libcxx into platforms that do not support pthread.
Original patch from Fulvio Esposito (fulvio.esposito@outlook.com) - D11781
Applied with tweaks - D19412
Change-Id: I301111f0075de93dd8129416e06babc195aa936b
llvm-svn: 268734
Summary:
when setting LIBCXX_ENABLE_EXCEPTIONS=false, _LIBCPP_NO_EXCEPTIONS wil be defined in both commandline and _config
Reviewers: bcraig, EricWF
Subscribers: cfe-commits
Differential Revision: http://reviews.llvm.org/D19344
llvm-svn: 266956
This patch is fairly large and contains a number of changes. The changes all work towards
allowing __tree to properly handle __value_type esspecially when inserting into the __tree.
I chose not to break this change into smaller patches because it wouldn't be possible to
write meaningful standard-compliant tests for each patch.
It is very similar to r260513 "[libcxx] Teach __hash_table how to handle unordered_map's __hash_value_type".
Changes in <map>
* Remove __value_type's constructors because it should never be constructed directly.
* Make map::emplace and multimap::emplace forward to __tree and remove the old definitions
* Remove "__construct_node" map and multimap member functions. Almost all of the construction is done within __tree.
* Fix map's move constructor to access "__value_type.__nc" directly and pass this object to __tree::insert.
Changes in <__tree>
* Add traits to detect, handle, and unwrap, map's "__value_type".
* Convert methods taking "value_type" to take "__container_value_type" instead. Previously these methods caused
unwanted implicit conversions from "std::pair<Key, Value>" to "__value_type<Key, Value>".
* Delete __tree_node and __tree_node_base's constructors and assignment operators. The node types should never be constructed
because the "__value_" member of __tree_node must be constructed directly by the allocator.
* Make the __tree_node_destructor class and "__construct_node" methods unwrap "__node_value_type" into "__container_value_type" before invoking the allocator. The user's allocator can only be used to construct and destroy the container's value_type. Passing it map's "__value_type" was incorrect.
* Cleanup the "__insert" and "__emplace" methods. Have __insert forward to an __emplace function wherever possible to reduce
code duplication. __insert_unique(value_type const&) and __insert_unique(value_type&&) forward to __emplace_unique_key_args.
These functions will not allocate a new node if the value is already in the tree.
* Change the __find* functions to take the "key_type" directly instead of passing in "value_type" and unwrapping the key later.
This change allows the find functions to be used without having to construct a "value_type" first. This allows for a number
of optimizations.
* Teach __move_assign and __assign_multi methods to unwrap map's __value_type.
llvm-svn: 264986
This adds clang thread safety annotations to std::mutex and
std::lock_guard so code using these types can use these types directly
instead of having to wrap the types to provide annotations. These checks
when enabled by -Wthread-safety provide simple but useful static
checking to detect potential race conditions.
See http://clang.llvm.org/docs/ThreadSafetyAnalysis.html for details.
This patch was reviewed in http://reviews.llvm.org/D14731.
llvm-svn: 263611
This patch is fairly large and contains a number of changes. The main change
is teaching '__hash_table' how to handle '__hash_value_type'. Unfortunately
this change is a rampant layering violation, but it's required to make
unordered_map conforming without re-writing all of __hash_table.
After this change 'unordered_map' can delegate to '__hash_table' in almost all cases.
The major changes found in this patch are:
* Teach __hash_table to differentiate between the true container value type
and the node value type by introducing the "__container_value_type" and
"__node_value_type" typedefs. In the case of unordered_map '__container_value_type'
is 'pair<const Key, Value>' and '__node_value_type' is '__hash_value_type'.
* Switch almost all overloads in '__hash_table' previously taking 'value_type'
(AKA '__node_value_type) to take '__container_value_type' instead. Previously
'pair<K, V>' would be implicitly converted to '__hash_value_type<K, V>' because
of the function signature.
* Add '__get_key', '__get_value', '__get_ptr', and '__move' static functions to
'__key_value_types'. These functions allow '__hash_table' to unwrap
'__node_value_type' objects into '__container_value_type' and its sub-parts.
* Pass '__hash_value_type::__value_' to 'a.construct(p, ...)' instead of
'__hash_value_type' itself. The C++14 standard requires that 'a.construct()'
and 'a.destroy()' are only ever instantiated for the containers value type.
* Remove '__hash_value_type's constructors and destructors. We should never
construct an instance of this type.
(TODO this is UB but we already do it in plenty of places).
* Add a generic "try-emplace" function to '__hash_table' called
'__emplace_unique_key_args(Key const&, Args...)'.
The following changes were done as cleanup:
* Introduce the '_LIBCPP_CXX03_LANG' macro to be used in place of
'_LIBCPP_HAS_NO_VARIADICS' or '_LIBCPP_HAS_NO_RVALUE_REFERENCE'.
* Cleanup C++11 only overloads that assume an incomplete C++11 implementation.
For example this patch removes the __construct_node overloads that do
manual pack expansion.
* Forward 'unordered_map::emplace' to '__hash_table' and remove dead code
resulting from the change. This includes almost all
'unordered_map::__construct_node' overloads.
The following changes are planed for future revisions:
* Fix LWG issue #2469 by delegating 'unordered_map::operator[]' to use
'__emplace_unique_key_args'.
* Rewrite 'unordered_map::try_emplace' in terms of '__emplace_unique_key_args'.
* Optimize '__emplace_unique' to call '__emplace_unique_key_args' when possible.
This prevent unneeded allocations when inserting duplicate entries.
The additional follow up work needed after this patch:
* Respect the lifetime rules for '__hash_value_type' by actually constructing it.
* Make '__insert_multi' act similar to '__insert_unique' for objects of type
'T&' and 'T const &&' with 'T = __container_value_type'.
llvm-svn: 260513
static_cast of a pointer to object before the start of the object's
lifetime has undefined behavior.
This code triggers CFI warnings.
This change replaces C-style casts with reinterpret_cast, which is
fine per the standard, add applies an attribute to silence CFI (which
barks on reinterpret_cast, too).
llvm-svn: 260441
This time I kept <ext/hash_map> working!
This patch is the first in a series of patches that's meant to better
support unordered_map. unordered_map has a special "value_type" that
differs from pair<const Key, Value>. In order to meet the EmplaceConstructible
and CopyInsertable requirements we need to teach __hash_table about this
special value_type.
This patch creates a "__hash_node_types" traits class that contains
all of the typedefs needed by the unordered containers and it's iterators.
These typedefs include ones for each node type and node pointer type,
as well as special typedefs for "unordered_map"'s value type.
As a result of this change all of the unordered containers now all support
incomplete types.
As a drive-by fix I changed the difference_type in __hash_table to always
be ptrdiff_t. There is a corresponding change to size_type but it cannot
take affect until an ABI break.
This patch will be followed up shortly with fixes for various unordered_map
bugs and problems.
llvm-svn: 260431
Operating systems that are not unix-like are unlikely to have access to
catopen. Instead of black-listing each one, we now filter out all non-unix
operating systems first. We then exclude the unix-like operating systems
that don't have catopen. _WIN32 counts as a unix-like operating system
because of cygwin.
http://reviews.llvm.org/D16639
llvm-svn: 260381
<string.h> and wcschr, wcspbrk, wcsrchr, wmemchr, and wcsstr from <wchar.h> to
provide a const-correct overload set even when the underlying C library does
not.
This change adds a new macro, _LIBCPP_PREFERRED_OVERLOAD, which (if defined)
specifies that a given overload is a better match than an otherwise equally
good function declaration without the overload. This is implemented in modern
versions of Clang via __attribute__((enable_if)), and not elsewhere.
We use this new macro to define overloads in the global namespace for these
functions that displace the overloads provided by the C library, unless we
believe the C library is already providing the correct signatures.
llvm-svn: 260337
Eric Fiselier