This reverts commit 087f065cb0c7463f521a62599884493aaee2ea12.
The tests were failing on 32 bit builds, and I don't have time
to clean them up right now. I'll recommit tomorrow with fixed tests.
llvm-svn: 347816
Summary:
Starting in Clang 8.0 and GCC 8.0, `alignof` and `__alignof` return different values in same cases. Specifically `alignof` and `_Alignof` return the minimum alignment for a type, where as `__alignof` returns the preferred alignment. libc++ currently uses `__alignof` but means to use `alignof`. See llvm.org/PR39713
This patch introduces the macro `_LIBCPP_ALIGNOF` so we can control which spelling gets used.
This patch does not introduce any ABI guard to provide the old behavior with newer compilers. However, if we decide that is needed, this patch makes it trivial to implement.
I think we should commit this change immediately, and decide what we want to do about the ABI afterwards.
Reviewers: ldionne, EricWF
Reviewed By: EricWF
Subscribers: christof, libcxx-commits
Differential Revision: https://reviews.llvm.org/D54814
llvm-svn: 347787
Summary:
std::dynarray had been proposed for C++14, but it was pulled out from C++14
and there are no plans to standardize it anymore.
Reviewers: mclow.lists, EricWF
Subscribers: mgorny, christof, jkorous, dexonsmith, arphaman, libcxx-commits
Differential Revision: https://reviews.llvm.org/D54801
llvm-svn: 347783
We don't support mac OS 10.6 and older anymore, so this macro can never
be defined. This bit of code had been added in D28931 as a fix for
PR31448, but it doesn't seem necessary anymore.
llvm-svn: 347427
Summary:
This silences the two -Wimplicit-fallthrough warnings clang finds in
ItaniumDemangle.h in libc++abi.
Clang does not have a GNU attribute spelling for this attribute, so this
is necessary.
I will commit the same change to the LLVM demangler soon.
Reviewers: EricWF, ldionne
Subscribers: christof, erik.pilkington, cfe-commits
Differential Revision: https://reviews.llvm.org/D53985
llvm-svn: 345870
Summary:
This patch makes the versioning namespace libc++ uses customizable by the user using `-DLIBCXX_ABI_NAMESPACE=__foo`.
This allows users to build custom versions of libc++ which can be linked into binaries with other libc++ versions without causing symbol conflicts or ODR issues.
Reviewers: mclow.lists, ldionne
Reviewed By: ldionne
Subscribers: kristina, smeenai, mgorny, phosek, libcxx-commits
Differential Revision: https://reviews.llvm.org/D53879
llvm-svn: 345657
Summary:
This commit adopts the exclude_from_explicit_instantiation attribute discussed
at [1] and reviewed in [2] in libc++ to supplant the use of __always_inline__
for visibility purposes.
This change means that users wanting to link together translation units built
with different versions of libc++'s headers into the same final linked image
MUST define the _LIBCPP_HIDE_FROM_ABI_PER_TU macro to 1 when building those
TUs. Doing otherwise will lead to ODR violations and ABI issues.
[1]: http://lists.llvm.org/pipermail/cfe-dev/2018-August/059024.html
[2]: https://reviews.llvm.org/D51789
Reviewers: rsmith, EricWF
Subscribers: dexonsmith, libcxx-commits
Differential Revision: https://reviews.llvm.org/D52405
llvm-svn: 345516
Summary:
When building with -fvisibility=hidden, some symbols do not get exported from
libc++.dylib. This means that some entities are not explicitly given default
visibility in the source code, and that we rely on the fact -fvisibility=default
is the default. This commit explicitly gives default visibility to those
symbols to avoid being dependent on the command line flags used.
The commit also remove symbols from the dylib -- those symbols do not
actually need to be exported from the dylib and this should not be an
ABI break.
Finally, in the future, we may want to mark the whole std:: namespace as
having hidden visibility (to switch from opt-out to opt-in), in which
case the changes done in this commit will be required.
Reviewers: EricWF
Subscribers: mgorny, christof, dexonsmith, libcxx-commits
Differential Revision: https://reviews.llvm.org/D52662
llvm-svn: 345260
That macro has been defined to _LIBCPP_HIDE_FROM_ABI_AFTER_V1 for many
weeks now, so we're actually replacing uses of it for uses of
_LIBCPP_HIDE_FROM_ABI_AFTER_V1 directly.
This should not change or break anything since the two macros are
100% equivalent, unless somebody is (incorrectly!) relying on
_LIBCPP_EXTERN_TEMPLATE_INLINE_VISIBILITY being defined.
llvm-svn: 344641
Revert r344535 "Wrap up the new chrono literals in an #ifdef..."
Revert r344546 "Mark a couple of test cases as 'C++17-only'..."
Some of the buildbot failures were masked by another error,
and this one was probably missed.
llvm-svn: 344580
There are two cases:
1. The library has all it needs to provide align_val_t and the
new/delete overloads needed to support aligned allocation.
2. The compiler has actually turned the language feature on.
There are times where libc++ needs to distinguish between the two.
This patch adds the additional macro
_LIBCPP_HAS_NO_LIBRARY_ALIGNED_ALLOCATION which denotes when case (1)
does not hold. _LIBCPP_HAS_NO_ALIGNED_ALLOCATION is defined whenever
_LIBCPP_HAS_NO_LIBRARY_ALIGNED_ALLOCATION is defined, or when the
compiler has not enabled the language feature.
Additionally this patch cleans up a number of other macros related
to detection of aligned allocation machinery.
llvm-svn: 344207
Summary:
The ABI version used by libc++ is a configuration option just like any other
configuration option. It is a knob that can be used by vendors to customize
the libc++ that they ship. As such, we should not be hardcoding vendor-specific
configuration choices in libc++.
When building libc++ for Fuchsia, Fuchsia's build scripts should simply define
the libc++ ABI version to 2 -- this will result in the _LIBCPP_ABI_VERSION
macro being defined in the __config header that is generated when libc++ is
built and installed, which is the correct way to customize libc++'s behavior
for specific vendors.
Reviewers: phosek, EricWF
Subscribers: mgorny, christof, dexonsmith, cfe-commits, libcxx-commits
Differential Revision: https://reviews.llvm.org/D52397
llvm-svn: 343079
Summary:
These deprecation warnings are opt-in: they are only enabled when the
_LIBCXX_DEPRECATION_WARNINGS macro is defined, which is not the case
by default. Note that this is a first step in the right direction, but
I wasn't able to get an exhaustive list of all deprecated components
per standard, so there's certainly stuff that's missing. The list of
components this commit marks as deprecated is:
in C++11:
- auto_ptr, auto_ptr_ref
- binder1st, binder2nd, bind1st(), bind2nd()
- pointer_to_unary_function, pointer_to_binary_function, ptr_fun()
- mem_fun_t, mem_fun1_t, const_mem_fun_t, const_mem_fun1_t, mem_fun()
- mem_fun_ref_t, mem_fun1_ref_t, const_mem_fun_ref_t, const_mem_fun1_ref_t, mem_fun_ref()
in C++14:
- random_shuffle()
in C++17:
- unary_negate, binary_negate, not1(), not2()
<rdar://problem/18168350>
Reviewers: mclow.lists, EricWF
Subscribers: christof, dexonsmith, llvm-commits
Differential Revision: https://reviews.llvm.org/D48912
llvm-svn: 342843
Summary:
The `[[nodiscard]]` attribute is intended to help users find bugs where
function return values are ignored when they shouldn't be. After C++17 the
C++ standard has started to declared such library functions as `[[nodiscard]]`.
However, this application is limited and applies only to dialects after C++17.
Users who want help diagnosing misuses of STL functions may desire a more
liberal application of `[[nodiscard]]`.
For this reason libc++ provides an extension that does just that! The
extension must be enabled by defining `_LIBCPP_ENABLE_NODISCARD`. The extended
applications of `[[nodiscard]]` takes two forms:
1. Backporting `[[nodiscard]]` to entities declared as such by the
standard in newer dialects, but not in the present one.
2. Extended applications of `[[nodiscard]]`, at the libraries discretion,
applied to entities never declared as such by the standard.
Users may also opt-out of additional applications `[[nodiscard]]` using
additional macros.
Applications of the first form, which backport `[[nodiscard]]` from a newer
dialect may be disabled using macros specific to the dialect it was added. For
example `_LIBCPP_DISABLE_NODISCARD_AFTER_CXX17`.
Applications of the second form, which are pure extensions, may be disabled
by defining `_LIBCPP_DISABLE_NODISCARD_EXT`.
This patch was originally written by me (Roman Lebedev),
then but then reworked by Eric Fiselier.
Reviewers: mclow.lists, thakis, EricWF
Reviewed By: thakis, EricWF
Subscribers: llvm-commits, mclow.lists, lebedev.ri, EricWF, rjmccall, Quuxplusone, cfe-commits, christof
Differential Revision: https://reviews.llvm.org/D45179
llvm-svn: 342808
Summary:
https://reviews.llvm.org/D49240 led to symbol size problems in Chromium, and
we expect this may be the case in other projects built in debug mode too.
Instead, unless users explicitly ask for internal_linkage, we use always_inline
like we used to.
In the future, when we have a solution that allows us to drop always_inline
without falling back on internal_linkage, we can replace always_inline by
that.
Note that this commit introduces a change in contract for existing libc++
users: by default, libc++ used to guarantee that TUs built with different
versions of libc++ could be linked together. With the introduction of the
_LIBCPP_HIDE_FROM_ABI_PER_TU macro, the default behavior is that TUs built
with different libc++ versions are not guaranteed to link. This is a change
in contract but not a change in behavior, since the current implementation
still allows linking TUs built with different libc++ versions together.
Reviewers: EricWF, mclow.lists, dexonsmith, hans, rnk
Subscribers: christof, cfe-commits
Differential Revision: https://reviews.llvm.org/D50652
llvm-svn: 339874
Summary:
The macros were inside `#if defined(_LIBCPP_COMPILER_CLANG)`, which means
we would never detect C11 features on non-Clang compilers. According to
Marshall Clow, this is not the intended behavior.
Reviewers: mclow.lists, EricWF
Subscribers: krytarowski, christof, dexonsmith, cfe-commits
Differential Revision: https://reviews.llvm.org/D50748
llvm-svn: 339741
Summary:
The current code enables aligned allocation functions when compiling in C++17
and later. This is a problem because aligned allocation functions might not
be supported on the target platform, which leads to an error at link time.
Since r338934, Clang knows not to define __cpp_aligned_new when it's not
available on the target platform -- this commit takes advantage of that to
only use aligned allocation functions when they are available.
Reviewers: vsapsai, EricWF
Subscribers: christof, dexonsmith, cfe-commits, EricWF, mclow.lists
Differential Revision: https://reviews.llvm.org/D50344
llvm-svn: 339431
Summary:
This macro allows hiding symbols from the ABI when the library is built
with an ABI version after ABI v1, which is currently the only stable ABI.
This commit defines `_LIBCPP_EXTERN_TEMPLATE_INLINE_VISIBILITY` to be
`_LIBCPP_HIDE_FROM_ABI_AFTER_V1`, meaning that symbols that were only
exported by the library for historical reasons are not exported anymore
in the unstable ABI.
Because of that, this commit is an ABI break for ABI v2. This ABI version
is not stable, however, so this should not be a problem.
Reviewers: EricWF, mclow.lists
Subscribers: christof, dexonsmith, cfe-commits
Differential Revision: https://reviews.llvm.org/D49914
llvm-svn: 339012
The warning happens when LIBCXX_ENABLE_EXCEPTIONS cmake option is not set,
and it fires every time __config is included, 33 in total.
Patch by Jason Lovett
Reviewed as https://reviews.llvm.org/D49997
llvm-svn: 338531
Summary:
This patch adds a new macro _LIBCPP_HAS_NO_VECTOR_EXTENSION for detecting
whether a vector extension (\_\_attribute\_\_((vector_size(num_bytes)))) is
available.
On the top of that, this patch implements the following API:
* all constructors
* operator[]
* copy_from
* copy_to
It also defines simd_abi::native to use vector extension, if available.
In GCC and Clang, certain values with vector extension are passed by registers,
instead of memory.
Based on D41148.
Reviewers: mclow.lists, EricWF
Subscribers: cfe-commits, MaskRay, lichray, sanjoy
Differential Revision: https://reviews.llvm.org/D41376
llvm-svn: 338309
Summary:
This commit introduces a new macro, _LIBCPP_HIDE_FROM_ABI, whose goal is to
mark functions that shouldn't be part of libc++'s ABI. It marks the functions
as being hidden for dylib visibility purposes, and as having internal linkage
using Clang's __attribute__((internal_linkage)) when available, and
__always_inline__ otherwise.
It replaces _LIBCPP_INLINE_VISIBILITY, which was always using __always_inline__
to achieve similar goals, but suffered from debuggability and code size problems.
The full proposal, along with more background information, can be found here:
http://lists.llvm.org/pipermail/cfe-dev/2018-July/058419.html
This commit does not rename uses of _LIBCPP_INLINE_VISIBILITY to
_LIBCPP_HIDE_FROM_ABI: this wide reaching but mechanical change can
be done later when we've confirmed we're happy with the new macro.
In the future, it would be nice if we could optionally allow dropping
any internal_linkage or __always_inline__ attribute, which could result
in code size improvements. However, this is currently impossible for
reasons explained here: http://lists.llvm.org/pipermail/cfe-dev/2018-July/058450.html
Reviewers: EricWF, dexonsmith, mclow.lists
Subscribers: christof, dexonsmith, llvm-commits, mclow.lists
Differential Revision: https://reviews.llvm.org/D49240
llvm-svn: 338122
This patch implements the <filesystem> header and uses that
to provide <experimental/filesystem>.
Unlike other standard headers, the symbols needed for <filesystem>
have not yet been placed in libc++.so. Instead they live in the
new libc++fs.a library. Users of filesystem are required to link this
library. (Also note that libc++experimental no longer contains the
definition of <experimental/filesystem>, which now requires linking libc++fs).
The reason for keeping <filesystem> out of the dylib for now is that
it's still somewhat experimental, and the possibility of requiring an
ABI breaking change is very real. In the future the symbols will likely
be moved into the dylib, or the dylib will be made to link libc++fs automagically).
Note that moving the symbols out of libc++experimental may break user builds
until they update to -lc++fs. This should be OK, because the experimental
library provides no stability guarantees. However, I plan on looking into
ways we can force libc++experimental to automagically link libc++fs.
In order to use a single implementation and set of tests for <filesystem>, it
has been placed in a special `__fs` namespace. This namespace is inline in
C++17 onward, but not before that. As such implementation is available
in C++11 onward, but no filesystem namespace is present "directly", and
as such name conflicts shouldn't occur in C++11 or C++14.
llvm-svn: 338093
Summary:
This is not guaranteed to work since the characters after '__has_include('
have special lexing rules that can't possibly be applied when
__has_include is generated by a macro. It also breaks the crash reproducers
generated by -frewrite-includes (see https://llvm.org/pr37990).
Reviewers: EricWF, rsmith, mclow.lists
Reviewed By: mclow.lists
Differential Revision: https://reviews.llvm.org/D49067
llvm-svn: 337824
Summary:
We never actually mean to always inline a function -- all the uses of
the macro I could find are actually attempts to control the visibility
of symbols. This is better described by _LIBCPP_INLINE_VISIBILITY, which
is actually always defined the same.
This change is orthogonal to the decision of what we're actually going
to do with _LIBCPP_INLINE_VISIBILITY -- it just simplifies things by
having one canonical way of doing things.
Note that this commit had originally been applied in r336369 and then
reverted in r336382 because of unforeseen problems. Both of these problems
have now been fixed.
Reviewers: EricWF, mclow.lists
Subscribers: christof, dexonsmith, erikvanderpoel
Differential Revision: https://reviews.llvm.org/D48892
llvm-svn: 336866
This reverts commit r336369. The commit had two problems:
1. __pbump was marked as _LIBCPP_EXTERN_TEMPLATE_INLINE_VISIBILITY instead of
_LIBCPP_INLINE_VISIBILITY, which lead to two symbols being added in the
dylib and the check-cxx-abilist failing.
2. The LLDB tests started failing because they undefine
`_LIBCPP_INLINE_VISIBILITY`. I need to figure out why they do that and
fix the tests before we can go forward with this change.
llvm-svn: 336382
Summary:
We never actually mean to always inline a function -- all the uses of
the macro I could find are actually attempts to control the visibility
of symbols. This is better described by _LIBCPP_INLINE_VISIBILITY, which
is actually always defined the same.
This change is orthogonal to the decision of what we're actually going
to do with _LIBCPP_INLINE_VISIBILITY -- it just simplifies things by
having one canonical way of doing things.
Reviewers: EricWF
Subscribers: christof, llvm-commits, dexonsmith, erikvanderpoel, mclow.lists
Differential Revision: https://reviews.llvm.org/D48892
llvm-svn: 336369
That's r333325, as well as follow-up "Fix GCC handling of ATOMIC_VAR_INIT"
r333327.
Marshall asked to revert:
Let's have a discussion about how to implement this so that it is more friendly
to people with installed code bases. We've had *extremely* loud responses to
unilaterally adding warnings - especially ones that can't be easily disabled -
to the libc++ code base in the past.
llvm-svn: 333351
Summary:
The atomic non-member functions accept pointers to std::atomic / std::atomic_flag as well as to the non-atomic value. These are all dereferenced unconditionally when lowered, and therefore will fault if null. It's a tiny gotcha for new users, especially when they pass in NULL as expected value (instead of passing a pointer to a NULL value). We can therefore use the nonnull attribute to denote that:
- A warning should be generated if the argument is null
- It is undefined behavior if the argument is null (because a dereference will segfault)
This patch adds support for this attribute for clang and GCC, and sticks to the subset of the syntax both supports. In particular, work around this GCC oddity:
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=60625
The attributes are documented:
- https://gcc.gnu.org/onlinedocs/gcc-4.0.0/gcc/Function-Attributes.html
- https://clang.llvm.org/docs/AttributeReference.html#nullability-attributes
I'm authoring a companion clang patch for the __c11_* and __atomic_* builtins, which currently only warn on a subset of the pointer parameters.
In all cases the check needs to be explicit and not use the empty nonnull list, because some of the overloads are for atomic<T*> and the values themselves are allowed to be null.
<rdar://problem/18473124>
Reviewers: arphaman, EricWF
Subscribers: aheejin, christof, cfe-commits
Differential Revision: https://reviews.llvm.org/D47225
llvm-svn: 333325
Summary:
It is immediately preceded by this check:
#if _MSC_VER < 1900
#error "MSVC versions prior to Visual Studio 2015 are not supported"
#endif
Reviewers: EricWF
Subscribers: christof, cfe-commits
Differential Revision: https://reviews.llvm.org/D45829
llvm-svn: 330360
This avoids the need for a custom generated config file which is desired
because the custom config files differs per-target which means we cannot
reuse headers across different targets.
Differential Revision: https://reviews.llvm.org/D45304
llvm-svn: 329770
this patch adds the <compare> header and implements all of it
except for [comp.alg].
As I understand it, the header is needed by the compiler in
when implementing the semantics of operator<=>. For that reason
I feel it's important to land this header early, despite
all compilers lacking support.
llvm-svn: 329460
This patch fixes std::allocator, and more specifically, all users
of __libcpp_allocate and __libcpp_deallocate, to support over-aligned
types.
__libcpp_allocate/deallocate now take an alignment parameter, and when
the specified alignment is greater than that supported by malloc/new,
the aligned version of operator new is called (assuming it's available).
When aligned new isn't available, the old behavior has been kept, and the
alignment parameter is ignored.
This patch depends on recent changes to __builtin_operator_new/delete which
allow them to be used to call any regular new/delete operator. By using
__builtin_operator_new/delete when possible, the new/delete erasure optimization
is maintained.
llvm-svn: 328180
This commit indents each level by two space characters, e.g.
#if defined(CONDITION)
# define _LIBCPP_NAME VALUE
#else
# define _LIBCPP_NAME VALUE
#endif
The simple #ifndef, #define, and #endif sequences are not indented, e.g.
#ifndef _LIBCPP_NAME
#define _LIBCPP_NAME ...
#endif
llvm-svn: 326027
An array T[1] isn't necessarily the same say when it's
a member of a struct. This patch addresses that problem and corrects
the tests to deal with it.
llvm-svn: 324545
Summary:
This patch fixes llvm.org/PR35491 and LWG2157 (https://cplusplus.github.io/LWG/issue2157)
The fix attempts to maintain ABI compatibility by replacing the array with a instance of `aligned_storage`.
Reviewers: mclow.lists, EricWF
Reviewed By: EricWF
Subscribers: lichray, cfe-commits
Differential Revision: https://reviews.llvm.org/D41223
llvm-svn: 324526
Some users may have a custom build system which gives a different
name to the libc++ archive (or does not create an archive at all,
instead passing the object files directly to the linker). Give those
users a way to disable auto-linking.
Differential Revision: https://reviews.llvm.org/D42436
llvm-svn: 323300
This is an MSVC standard library extension. It seems like a reasonable
enough extension to me because wchar_t* is the native format for
filenames on that platform.
Differential Revision: https://reviews.llvm.org/D42225
llvm-svn: 323170
Inline the provided "fallback" definitions (which seem to always be
taken) that expand to __cdecl into users. The fallback definitions
for the *CRTIMP* macros were wrong in the case where the CRT is being
linked statically, so define our own macro as a replacement.
Differential Revision: https://reviews.llvm.org/D42158
llvm-svn: 322617
An application may determine whether the C standard library is glibc
by testing whether __GLIBC_PREREQ is defined. This breaks if libc++
provides its own definition. Instead, define our own macro in our
namespace with the desired semantics.
Differential Revision: https://reviews.llvm.org/D41892
llvm-svn: 322201
It turns out that this is the only change required in libcxx
for it to compile with the new `wasm32-unknown-unknown-wasm`
target recently added to Clang.
Patch by Nicholas Wilson!
Differential Revision: https://reviews.llvm.org/D41073
llvm-svn: 320925
The MSVC driver and clang do not link against the C++ runtime
explicitly. Instead, they rely on the auto-linking via the pragma
(through `use_ansi.h`) to link against the correct version of the C++
runtime. Attempt to do something similar here so that linking real C++
code on Windows does not require the user to explicitly specify
`c++.lib` when using libc++ as a C++ runtime on windows.
llvm-svn: 319816
Use this source use on Fuchsia where this is the oficially way
to obtain randomness. This could be also used on other platforms
that already support getentropy such as *BSD or Linux.
Differential Revision: https://reviews.llvm.org/D40319
llvm-svn: 319523
Fix the problem PR31516 with setting locale on Windows by wrapping
_locale_t with a pointer-like class.
Reduces 74 test failures in std/localization test suite to 47 test
failures (on llvm clang, Visual Studio 2015). Number of test failures
doesn't depend on the platform (x86 or x64).
Patch by Andrey Khalyavin.
Differential Revision: https://reviews.llvm.org/D40181
llvm-svn: 318902
Summary:
Currently `std::variant` always uses an unsigned int to store the variant index. However this isn't nessesary and causes `std::variant` to be larger than it needs to be in most cases.
This patch changes the index type to be `unsigned char` when possible, and `unsigned short` or `unsigned int` otherwise, depending on the size (Although it's questionable if it's even possible to create a variant with 65535 elements.
Unfortunately this change is an ABI break, and as such is only enabled in ABI v2.
Reviewers: mpark
Reviewed By: mpark
Subscribers: cfe-commits
Differential Revision: https://reviews.llvm.org/D40210
llvm-svn: 318621
Summary:
quick_exit() and at_quick_exit() were introduced in android NDK 21:
https://android.googlesource.com/platform/prebuilts/ndk/+/dev/platform/sysroot/usr/include/stdlib.h#55
This CL conditions `_LIBCPP_HAS_QUICK_EXIT` on `__ANDROID_API__ >= 21`. The only place this macro is used is in some using declarations: `using ::quick_exit`, `using ::at_quick_exit`.
Also, add a missing include to sys/cdefs.h which is what defines `__BIONIC__`.
Reviewers: thakis, danalbert, EricWF
Reviewed By: danalbert
Subscribers: srhines, krytarowski
Differential Revision: https://reviews.llvm.org/D39479
llvm-svn: 317124
Previously this macro used 0/1 to indicate if it was set.
This is unlike all other libc++ configuration macros which
use ifdef/ifndef.
This patch makes this macro consistent with everything else.
llvm-svn: 315995
Make it clear that these are intended only to force a specific ABI when
the autodetection would give the wrong result by renaming the cmake
options and adding separate forcing macros, as suggested by EricWF in
the post-commit review of r314949 and further discussed on IRC.
llvm-svn: 314965
libc++'s current heuristic for detecting Itanium vs. Microsoft ABI falls
short in some cases. For example, it will detect windows-itanium targets
as using the Microsoft ABI, since they set `_MSC_VER` (for compatibility
with Microsoft headers). Leave the current heuristic in place by default
but also allow users to explicitly specify the ABI if need be.
llvm-svn: 314949
Some targets (e.g. Darwin) might have the Win32 API available, but they
do not use MSVC CRT. Assume _LIBCPP_MSVCRT only when _MSC_VER is available
and __MINGW32__ isn't defined.
Differential Revision: https://reviews.llvm.org/D34588
rdar://problem/32628786
llvm-svn: 308225
This reverts commit r306310.
r306310 causes clang to reject a call to an aligned allocation or
deallocation function if it is not implemented in the standard library
of the deployment target. This is not the desired behavior when users
have defined their own aligned functions.
rdar://problem/32664169
llvm-svn: 306859
attribute.
This is needed because older versions of libc++ do not have these
operators. If users target an older deployment target and try to compile
programs in which these operators are explicitly called, the compiler
will complain.
The following is the list of minimum deployment targets for the four
OSes:
macosx: 10.13
ios: 11.0
tvos: 11.0
watchos: 4.0
rdar://problem/32664169
Differential Revision: https://reviews.llvm.org/D34556
llvm-svn: 306310
Fix an off-by-one in r302172, which triggered building local versions of
the iostreams when deploying to `<= macOS 10.9`, when it should have
been `< macOS 10.9`. 10.9 had the dylib support.
This defines `_LIBCPP_AVAILABILITY_NO_STREAMS_EXTERN_TEMPLATE` less
often, reducing code size for users with deployment targets of exactly
macOS 10.9 or iOS 7.0.
rdar://problem/32233981
llvm-svn: 305649
C99 at least. C89 still fails due to the use of block comments.
NOTE: Having libc++ on the include path when compiling C is not
recommended or ever really supported. However it happens often
enough that this change is warrented.
llvm-svn: 305539
The function num_get<_CharT>::stage2_int_prep makes unnecessary copy of src
into atoms when char_type is char. This can be avoided by creating
a switch on type and just returning __src when char_type is char.
Added the test case to demonstrate performance improvement.
In order to avoid ABI incompatibilities, the changes are guarded
with a macro _LIBCPP_ABI_OPTIMIZED_LOCALE_NUM_GET
Differential Revision: https://reviews.llvm.org/D30268
Reviewed by: EricWF
llvm-svn: 305427
Summary:
This patch improves how libc++ handles min/max macros within the headers. Previously libc++ would undef them and emit a warning.
This patch changes libc++ to use `#pragma push_macro` to save the macro before undefining it, and `#pragma pop_macro` to restore the macros and the end of the header.
Reviewers: mclow.lists, bcraig, compnerd, EricWF
Reviewed By: EricWF
Subscribers: cfe-commits, krytarowski
Differential Revision: https://reviews.llvm.org/D33080
llvm-svn: 304357
Clang started providing -fcoroutines and defining __cpp_coroutines
way before it implemented the __builtin_coro_foo functions. This
means that simply checking if __cpp_coroutines is not a sufficient
way of detecting the actual feature.
This patch implements _LIBCPP_HAS_NO_COROUTINES which implements
a slightly more complex feature check. Specifically it requires
__cpp_coroutines >= 201703L, which only holds for Clang 5.0 built
after 2017/05/24.
llvm-svn: 303956
Some MinGW configurations use WinPThread instead of the native
threading interfaces. When this happens libc++ doesn't build because
it tries to use the wrong threading API.
This patch attempts to correctly detect and enable pthreads; Selecting
them when __MINGW32__ is defined and __has_include(<pthread.h>) is true.
I'm not sure if this works correctly 100% of the time but it seemed
like the most correct approach available.
llvm-svn: 302734
Libc++ is used as a system library on macOS and iOS (amongst others). In order
for users to be able to compile a binary that is intended to be deployed to an
older version of the platform, clang provides the
availability attribute <https://clang.llvm.org/docs/AttributeReference.html#availability>_
that can be placed on declarations to describe the lifecycle of a symbol in the
library.
See docs/DesignDocs/AvailabilityMarkup.rst for more information.
Differential Revision: https://reviews.llvm.org/D31739
llvm-svn: 302172
Fuchsia's libc was forked from musl, but has evolved sufficiently
since then so it no longer makes sense to pretend it's musl. This
change implements direct support for Fuchsia rather than
piggybacking on musl support.
Differential Revision: https://reviews.llvm.org/D31970
llvm-svn: 300261
When the libc++ extern template macros were added, the intent was for it
to be possible for consumers of the headers to disable extern templates
(via `-D_LIBCPP_EXTERN_TEMPLATE(...)=`). Unfortunately, support for
specifying function-like macros varies on the command line varies across
compilers (e.g. MSVC doesn't support it at all), and cmake doesn't allow
it for the same reason. Add a non-function macro for this purpose.
The intended use is for libraries which want to use the libc++ headers
without taking a dependency on the libc++ library itself. I can name the
macro something which reflects its intent rather than its behavior (e.g.
`_LIBCPP_HEADER_ONLY`) if desired.
Differential Revision: https://reviews.llvm.org/D31725
llvm-svn: 300246
The inline function definition ABI macro is gated on COFF dllexport
semantics, so it's more appropriate to mark it with the object file
format macro rather than the generic _WIN32 macro. We now have no uses
of _WIN32 apart from those used to define the other Windows macros :)
Clarify the ABI macro comment and make the object file format check
exhaustive while I'm here.
llvm-svn: 300097
r145698 introduced _LIBCPP_HAS_NO_STRONG_ENUMS by copy-pasting the
__has_feature check from objc_arc_weak/_LIBCPP_HAS_OBJC_ARC_WEAK, and
accidentally started defining _LIBCPP_HAS_NO_STRONG_ENUMS whenever
__has_feature(objc_arc_weak). This is totally bogus, and means that
Libc++ thinks Objective-C++ compilations with -fobjc-arc don't have
strong enums.
Delete the accidental line.
I thought about adding a test, but it would be entirely duplicative of
the patch (if has-feature strong enums, check that has-no-strong-enums
is not defined).
llvm-svn: 299236
Summary:
bad_function_call is currently an empty class, so any object files using
that class will end up with their own copy of its typeinfo, typeinfo
name and vtable, leading to unnecessary duplication that has to be
resolved by the dynamic linker. Instead, give bad_function_call a key
function and put a definition for that key function in libc++ itself, to
centralize the typeinfo and vtable.
This is consistent with the behavior for other exception classes. The
key functions are defined in libc++ rather than libc++abi since the
class is defined in the libc++ versioning namespace, so ABI
compatibility with libstdc++ is not a concern.
Guard this change behind an ABI macro, since it isn't backwards
compatible (i.e., clients built against the new libc++ headers wouldn't
be able to run against an older libc++ library).
Reviewers: mclow.lists, EricWF
Subscribers: mgorny, cfe-commits
Differential Revision: https://reviews.llvm.org/D27387
llvm-svn: 298937
Put proper guards around _LIBCPP_METHOD_TEMPLATE_IMPLICIT_INSTANTIATION_VIS.
No functional change on non-Windows. Avoids incorrect macro redefinition
on Windows.
llvm-svn: 297330
Summary:
Most classes annotated with _LIBCPP_TYPE_VIS need to have at least some
of their members exported, otherwise we have a lot of link errors when
linking against a libc++ built with hidden visibility. This also makes
_LIBCPP_TYPE_VIS be consistent across platforms, since on Windows it
already exports members.
With this change made, any template methods of a class marked
_LIBCPP_TYPE_VIS will also get default visibility when instantiatied,
which is not desirable for clients of libc++ headers who wish to control
their visibility; this is the same issue as PR30642. Annotate all
problematic methods with an explicit visibility specifier to avoid this.
The problematic methods were found by running bad-visibility-finder [1]
against the libc++ headers after making the _LIBCPP_TYPE_VIS change. The
small methods were marked for inlining; the larger ones hidden.
[1] https://github.com/smeenai/bad-visibility-finder
Reviewers: mclow.lists, EricWF
Subscribers: cfe-commits
Differential Revision: https://reviews.llvm.org/D25208
llvm-svn: 296732
When building libc++ with hidden visibility, we want explicit template
instantiations to export members. This is consistent with existing
Windows behavior, and is necessary for clients to be able to link
against a hidden visibility built libc++ without running into lots of
missing symbols.
An unfortunate side effect, however, is that any template methods of a
class with an explicit instantiation will get default visibility when
instantiated, unless the methods are explicitly marked inline or hidden
visibility. This is not desirable for clients of libc++ headers who wish
to control their visibility, and led to PR30642.
Annotate all problematic methods with an explicit visibility specifier
to avoid this. The problematic methods were found by running
https://github.com/smeenai/bad-visibility-finder against the libc++
headers after making the _LIBCPP_EXTERN_TEMPLATE_TYPE_VIS change. The
methods were marked with the new _LIBCPP_METHOD_TEMPLATE_IMPLICIT_INSTANTIATION_VIS
macro, which was created for this purpose.
It should be noted that _LIBCPP_EXTERN_TEMPLATE_TYPE_VIS was originally
intended to expand to default visibility, and was changed to expanding
to default type visibility to fix PR30642. The visibility macro
documentation was not updated accordingly, however, so this change makes
the macro consistent with its documentation again, while explicitly
fixing the methods which resulted in that PR.
Differential Revision: https://reviews.llvm.org/D29157
llvm-svn: 296731
GCC 7.0.1 started warning that __attribute__((__strong__)) is depricated.
This patch switches to using inline namespace with GCC instead. I believe
this wasn't done originally in order to support older GCC versions w/o
support for inline namespaces, or because earlier versions of GCC warned
users that the STL was using an inline namespace (even though it shouldn't affect users).
However I believe all of the above problems are gone for GCC 4.9 and greater.
Therefore switching to using inline namespaces instead of using __strong__
is the most correct behavior.
llvm-svn: 295428
Summary:
This patch implements [P0003R5](http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2016/p0003r5.html) which removes exception specifications from C++17.
The only changes to the library are removing `set_unexpected`, `get_unexpected`, `unexpected`, and `unexpected_handler`. These functions can be re-enabled in C++17 using `_LIBCPP_ENABLE_CXX17_REMOVED_UNEXPECTED_FUNCTIONS`.
@mclow.lists what do you think about removing stuff is this way?
Reviewers: mclow.lists
Reviewed By: mclow.lists
Subscribers: mclow.lists, cfe-commits
Differential Revision: https://reviews.llvm.org/D28172
llvm-svn: 295406
clang cannot properly handle __declspec and __attribute__ on classes
right now. This prevents the shared_mutex tests from working. Disable
the use of the annotation on COFF targets.
llvm-svn: 294958
It is my opinion that libc++ should never use `<cassert>`, including in the `dylib`.
This patch remove all uses of `assert` from within libc++ and replaces most of them with `_LIBCPP_ASSERT` instead.
Additionally this patch turn `LIBCXX_ENABLE_ASSERTIONS` off by default,
because the standard library should not be aborting user programs unless explicitly asked to.
llvm-svn: 294107
This causes unnecessary warnings when building with `cl`. Newer
versions of the C standard permit the redefinition of the macro to the
same value (which is the case here), unfortunately, `cl` does not yet
implement this. Add a check to prevent the redefinition.
llvm-svn: 293439
This reverts commit r292883. Unfortunately <string_view> uses
_LIBCPP_ASSERT in a way which is not compatible with the C++11 dylib
build. I'll investigate more tomorrow.
llvm-svn: 292923
Summary:
It is my opinion that libc++ should never use `<cassert>`, including in the `dylib`. This patch remove all uses of `assert` from within libc++ and replaces most of them with `_LIBCPP_ASSERT` instead.
Additionally this patch turn `LIBCXX_ENABLE_ASSERTIONS` off by default, because the standard library should not be aborting user programs unless explicitly asked to.
Reviewers: mclow.lists, compnerd, smeenai
Reviewed By: mclow.lists
Subscribers: mgorny, cfe-commits
Differential Revision: https://reviews.llvm.org/D29063
llvm-svn: 292883
<string> uses `decltype` in a way incompatible with `__typeof__`.
This is problematic when compiling <string> with Clang 3.4 because
even though it provides `__decltype` libc++ still used `__typeof__`
because clang 3.4 doesn't provide __is_identifier which libc++
uses to detect __decltype.
This patch manually detects Clang 3.4 and properly configures
for it.
llvm-svn: 292833
Summary:
This patch disables the aligned new/delet overloads on Apple platforms without `posix_memalign`. This fixes libc++.dylib build regressions on such platforms.
This fixes http://llvm.org/PR31448.
This patch should also be merged into the 4.0 release branch
Reviewers: mclow.lists, rsmith, dexonsmith, jeremyhu
Reviewed By: mclow.lists
Subscribers: cfe-commits
Differential Revision: https://reviews.llvm.org/D28931
llvm-svn: 292564
Summary: This patch adjusts the newly added `msvc_stdlib_force_include.hpp` so that it also works when used with `clang++`.
Reviewers: STL_MSFT
Reviewed By: STL_MSFT
Differential Revision: https://reviews.llvm.org/D28917
llvm-svn: 292539
In order to allow inlining of previously out-of-line functions without an ABI break
libc++ provides legacy definitions in the dylib that old programs can
continue to use. Unfortunatly Windows link.exe detects this hack and diagnoses the duplicate
definitions.
This patch disable the duplicate definitions on Windows by adding an ABI option
which disables all "legacy out-of-line symbols"
llvm-svn: 292190
MSVC/clang-cl doesn't do a full EBO unless __declspec(empty_bases)
is applied to the derived type. This causes certain tuple tests
to fail.
This patch adds the empty_bases attribute to __tuple_impl in order
for tuple to fully provide the EBO.
llvm-svn: 292159
Summary: On Windows tests that use `_LIBCPP_ASSERT` fail to link because the assertion handler function isn't correctly exported from the libc++ dylib. This patch fixes the dll import/export issues by introducing a new visibility macro `_LIBCPP_EXTERN_VIS` for use on external variables.
Reviewers: compnerd, smeenai, EricWF
Reviewed By: EricWF
Subscribers: cfe-commits
Differential Revision: https://reviews.llvm.org/D28728
llvm-svn: 292158
When -pedantic-errors is specified `__has_extension(<feature>)` is always
false when it would otherwise be true. This causes C++03 <atomic> to break
along with other issues.
This patch avoids the above problem by using __is_identifier(...) instead since
it is not affected by -pedantic-errors. For example instead of checking for
__has_extension(c_atomics) we now check `!__is_identifier(_Atomic)`, which
is only true when _Atomic is not a keyword provided by the compiler.
This patch applies similar changes to the detection logic for __decltype and
__nullptr as well.
Note that it does not apply this change to the C++03
`static_assert` macro since -Wc11-extensions warnings generated by expanding
that macro will appear in user code, and will not be suppressed as part of a
system header.
llvm-svn: 291995
Clang recently added a `diagnose_if(cond, msg, type)` attribute
which can be used to generate diagnostics when `cond` is a constant
expression that evaluates to true. Otherwise no attribute has no
effect.
This patch adds _LIBCPP_DIAGNOSE_ERROR/WARNING macros which
use this new attribute. Additionally this patch implements
a diagnostic message when a non-const-callable comparator is
given to a container.
Note: For now the warning version of the diagnostic is useless
within libc++ since warning diagnostics are suppressed by the
system header pragma. I'm going to work on fixing this.
llvm-svn: 291961
This tells whether or not the builtin function __builtin_memcmp is constexpr.
Only defined for clang 4.0 and later, and not true for any shipping version of Apple's clang.
llvm-svn: 291773
Add an implementation for the Win32 threading model as a backing API for
the internal c++ threading interfaces. This uses the Fls* family for
the TLS (which has the support for adding termination callbacks),
CRITICAL_SECTIONs for the recursive mutex, and Slim Reader/Writer locks
(SRW locks) for non-recursive mutexes. These APIs should all be
available on Vista or newer.
llvm-svn: 291333
This patch adds a libc++ configuration macro for the ABI we
are targeting, either Itanium or Microsoft. For now we configure
for the Microsoft ABI when on Windows with a compiler that defines
_MSC_VER. However this is only temporary until Clang implements
builtin macros we can use.
llvm-svn: 291329
This patch refactors the compiler detection done in `__config` by creating a
set of `_LIBCPP_COMPILER_<TYPE>` macros. The goal of this patch is to make
it easier to detect what compiler is being used outside of `__config`.
Additionally this patch removes workarounds for GCC in `__bit_reference`. I
tested GCC 4.8 and 4.9 without the workaround and neither seemed to need it
anymore.
llvm-svn: 291286
Summary:
This patch attempts to clean up the macro configuration mess in `<__threading_support>`, specifically the mess involving external threading variants. Additionally this patch adds design documentation for `<__threading_support>` and the configuration macros it uses.
The primary change in this patch is separating the idea of an "external API" provided by `<__external_threading>` and the idea of having an external threading library. Now `_LIBCPP_HAS_THREAD_API_EXTERNAL` means that libc++ should use `<__external_threading>` and that the header is expected to exist. Additionally the new macro `_LIBCPP_HAS_THREAD_LIBRARY_EXTERNAL` is now used to configure for using an "external library" with the default threading API.
Reviewers: compnerd, rmaprath
Subscribers: smeenai, cfe-commits, mgorny
Differential Revision: https://reviews.llvm.org/D28316
llvm-svn: 291275
In the C++ standard `std::pointer_safety` is defined
as a C++11 strongly typed enum. However libc++ currently defines
it as a class type which simulates a C++11 enumeration. This
can be detected in valid C++ code.
This patch introduces an the _LIBCPP_ABI_POINTER_SAFETY_ENUM_TYPE ABI option.
When defined `std::pointer_safety` is implemented as an enum type.
Unfortunatly this also means it can no longer be provided as an extension
in C++03.
Additionally this patch moves the definition for `get_pointer_safety()`
out of the dylib, and into the headers. New usages of `get_pointer_safety()`
will now use the inline version instead of the dylib version. However in
order to keep the dylib ABI compatible the old definition is explicitly
compiled into it.
llvm-svn: 291046
The name _LIBCPP_TYPE_VIS_ONLY is no longer accurate because both
_LIBCPP_TYPE_VIS and _LIBCPP_TYPE_VIS_ONLY expand to
__attribute__((__type_visibility__)) with Clang. The only remaining difference
is that _LIBCPP_TYPE_VIS_ONLY can be applied to templates whereas
_LIBCPP_TYPE_VIS cannot (due to dllimport/dllexport not being allowed on
templates).
This patch renames _LIBCPP_TYPE_VIS_ONLY to _LIBCPP_TEMPLATE_VIS.
llvm-svn: 291035
MSVC 19+ and clang-cl with emulation version >= 19.00 will provide
char{16,32}_t as builtin types. Adjust the configuration accordingly.
llvm-svn: 290940
Introduce a `_LIBCPP_HAS_BITSCAN64` macro to specify if the 64-bit
variant of the bitscan family of APIs is available. This avoids
duplicating the check in the support header.
llvm-svn: 290924
Replace the use of _WIN32 in libc++. Replace most use with a C runtime
check _LIBCPP_MSVCRT or the new _LIBCPP_WIN32 to indicate that we are
using the Win32 API. Use a new _LIBCPP_WCHAR_IS_UCS2 to indicate that we
are on an environment that has a short wchar_t.
llvm-svn: 290910
Currently libc++ compiles a special version of error_category()
into the dylib. This definition is no longer needed, and doesn't
work on Windows due to dllimport/dllexport semantics.
For those reasons this patch introduces an option to
disable/enable this definition. By default the definition
is provided in ABI v1 except on windows. This patch
also addresses D28210.
llvm-svn: 290840
In the previous fix I used a PMF type as a semi-safe bool type in C++03.
However immediately after committing I realized clang offered explicit
conversion operators as an extension. This patch removes the old fix and
enables _LIBCPP_EXPLICIT using __has_extension instead.
This change also affects the following other classes, which have
'_LIBCPP_EXPLICIT operator bool()'.
* shared_ptr
* unique_ptr
* error_condition
* basic_ios
* function (already C++11 only)
* istream::sentry
* experimental::string_view.
In all of the above cases I believe it is safe to enable the extension, except
in the experimental::string_view case. There seem to be some Clang bugs
affecting the experimental::string_view conversion to std::basic_string. To
work around that I manually disabled _LIBCPP_EXPLICIT in that case.
llvm-svn: 290831
There were two problems with the initial fix.
1. The added tests flushed out that we misconfigured _LIBCPP_EXPLICIT with GCC.
2. Because the boolean type was a member function template it caused weird link
errors. I'm assuming due to the vague linkage rules. This time the bool type
is a non-template member function pointer. That seems to have fixed the
failing tests. Plus it will end up generating less symbols overall, since
the bool type is no longer per instantiation.
original commit message below
-----------------------------
std::basic_ios has an operator bool(). In C++11 and later
it is explicit, and only allows contextual implicit conversions.
However explicit isn't available in C++03 which causes std::istream (et al)
to have an implicit conversion to int. This can easily cause ambiguities
when calling operator<< and operator>>.
This patch uses a "bool-like" type in C++03 to work around this. The
"bool-like" type is an arbitrary pointer to member function type. It
will not convert to either int or void*, but will convert to bool.
llvm-svn: 290754
Back in r240527 I added a knob to prevent thread-unsafe functions from
being exposed. mblen(), mbtowc() and wctomb() were also added to this
list, as the latest issue of POSIX doesn't require these functions to be
thread-safe.
It turns out that the only circumstance in which these functions are not
thread-safe is in case they are used in combination with state-dependent
character sets (e.g., Shift-JIS). According to Austin Group Bug 708,
these character sets "[...] are mostly a relic of the past and which
were never supported on most POSIX systems".
Though in many cases the use of these functions can be prevented by
using the reentrant counterparts, they are the only functions that allow
you to query whether the locale's character set is state-dependent. This
means that omitting these functions removes actual functionality.
Let's be a bit less pedantic and drop the guards around these functions.
Links:
http://austingroupbugs.net/view.php?id=708http://www.open-std.org/jtc1/sc22/wg14/www/docs/n2037.htm
Reviewed by: ericwf
Differential Revision: https://reviews.llvm.org/D21436
llvm-svn: 290748
In C++03 libc++ emulates nullptr_t using a class, and #define's nullptr.
However this makes nullptr_t mangle differently between C++03 and C++11.
This breaks any function ABI which takes nullptr_t.
Thanfully Clang provides __nullptr in all dialects. This patch adds
an ABI option to switch to using __nullptr in C++03. In a perfect world
I would like to turn this on by default, since it's just ABI breaking fix
to an ABI breaking bug.
llvm-svn: 290662
This patch implements changes to allow _LIBCPP_ASSERT to throw on failure
instead of aborting. The main changes needed to do this are:
1. Change _LIBCPP_ASSERT to call a handler via a replacable function pointer
instead of calling abort directly. Additionally this patch implements two
handler functions, one which aborts and another that throws an exception.
2. Add _NOEXCEPT_DEBUG macro for disabling noexcept spec on function which
contain _LIBCPP_ASSERT. This is required in order to prevent assertion
failures throwing through a noexcept function. This macro has no effect
unless _LIBCPP_DEBUG_USE_EXCEPTIONS is defined.
Having a non-aborting _LIBCPP_ASSERT is very important to allow sane testing of
debug mode. Currently we can only have one test case per file, since the test
case will cause the program to abort. Testing debug mode this way would require
thousands of test files, most of which would be 95% boiler plate. I don't think
this is a feasible strategy. Fortunately using a throwing debug handler solves
these issues.
Additionally this patch rewrites the documentation for debug mode.
llvm-svn: 290651
It's useful to be able to disable visibility annotations entirely; for
example, if we're building libc++ static to include in another library,
and we don't want any libc++ functions getting exported out of that
library. This is a generalization of _LIBCPP_DISABLE_DLL_IMPORT_EXPORT.
Differential Revision: https://reviews.llvm.org/D26934
llvm-svn: 288690
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
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
fixes.
llvm-svn: 260012
Summary:
This patch is similar to the <list> fix but it has a few differences. This patch doesn't use a `__link_pointer` typedef because we don't need to change the linked list pointers because `forward_list` never stores a `__forward_begin_node` in the linked list itself.
The issue with `forward_list` is that the iterators store pointers to `__forward_list_node` and not `__forward_begin_node`. This is incorrect because `before_begin()` and `cbefore_begin()` return iterators that point to a `__forward_begin_node`. This means we incorrectly downcast the `__forward_begin_node` pointer to a `__node_pointer`. This downcast itself is sometimes UB but it cannot be safely removed until ABI v2. The more common cause of UB is when we deference the downcast pointer. (for example `__ptr_->__next_`). This can be fixed without an ABI break by upcasting `__ptr_` before accessing it.
The fix is as follows:
1. Introduce a `__iter_node_pointer` typedef that works similar to `__link_pointer` in the last patch. In ABI v2 it is always a typedef for `__begin_node_pointer`.
2. Change the `__before_begin()` method to return the correct pointer type (`__begin_node_pointer`),
Previously it incorrectly downcasted the `__forward_begin_node` to a `__node_pointer` so it could be used to constructor the iterator types.
3. Change `__forward_list_iterator` and `__forward_list_const_iterator` in the following way:
1. Change `__node_pointer __ptr_;` member to have the `__iter_node_pointer` type instead.
2. Add additional private constructors that accept `__begin_node_pointer` in addition to `__node_pointer` and then correctly cast them to the stored `__iter_node_pointer` type.
3. Add `__get_begin()` and `__get_node_unchecked()` accessor methods that correctly cast `__ptr_` to the expected pointer type. `__get_begin()` is always safe to use and should be
preferred. `__get_node_unchecked()` can only be used on a deferencible iterator.
4. Replace direct access to `__forward_list_iterator::__ptr_` with the safe accessor methods.
Reviewers: mclow.lists, EricWF
Subscribers: cfe-commits
Differential Revision: http://reviews.llvm.org/D15836
llvm-svn: 258888
Summary:
This patch fixes std::list for builtin pointer types in the current ABI version and fixes std::list for all fancy pointer types in the next ABI version. The patch was designed to minimize the amount of code needed to support both ABI configurations. Currently only ~5 lines of code differ.
Reviewers: danalbert, jroelofs, mclow.lists
Subscribers: dexonsmith, awi, cfe-commits
Differential Revision: http://reviews.llvm.org/D12299
llvm-svn: 256652
Summary:
This patch allows GCC 4.6 and above to use `noexcept` as opposed to `throw()`.
Is it an ABI safe change to suddenly switch on `noexcept`? I imagine it must be because it's disabled in w/ clang in C++03 but not C++11.
Reviewers: danalbert, jroelofs, mclow.lists
Subscribers: cfe-commits
Differential Revision: http://reviews.llvm.org/D15516
llvm-svn: 255683
This patch goes through and enables C++11 and C++14 features for newer GCC's.
The main changes are:
1. Turn on variable templates. (Uses __cpp_variable_templates)
2. Assert atomic<Tp> is trivially copyable (Uses _GNUC_VER >= 501).
3. Turn on trailing return support for GCC. (Uses _GNUC_VER >= 404)
4. XFAIL void_t test for GCC 5.1 and 5.2. Fixed in GCC 6.
llvm-svn: 255585
Summary:
Also, there are no exported character type tables from Musl so we have to
Fallback to the standard functions. This reduces the number of libcxx's
test-suite failures down to ~130 for MIPS. Most of the remaining failures
come from the atomics (due to the lack of 8-byte atomic-ops in MIPS32) and
thread tests.
Reviewers: mclow.lists, EricWF, dalias, jroelofs
Subscribers: tberghammer, danalbert, srhines, cfe-commits
Differential Revision: http://reviews.llvm.org/D14926
llvm-svn: 253972
Summary:
This patch adds the LIBCXX_LIBC_IS_MUSL cmake option to allow the
building of libcxx with the Musl C library. The option is necessary as
Musl does not provide any predefined macro in order to test for its
presence, like GLIBC. Most of the changes specify the correct path to
choose through the various #if/#else constructs in the locale code.
Depends on D13407.
Reviewers: mclow.lists, jroelofs, EricWF
Subscribers: jfb, tberghammer, danalbert, srhines, cfe-commits
Differential Revision: http://reviews.llvm.org/D13673
llvm-svn: 252457
Allow deque and deque::iterator instantiation with incomplete element
type. This is an ABI breaking change, and it is only enabled if
LIBCXX_ABI_VERSION >= 2 or LIBCXX_ABI_UNSTABLE=ON.
llvm-svn: 252350
C++ macros and CMake options that specify the default ABI version of
the library, and can be overridden to pick up new ABI-changing
features.
llvm-svn: 250254
Previously, this resulted in us declaring a template for static_assert emulation within the 'extern "C"' context, which is ill-formed.
llvm-svn: 250247
Summary:
After putting this question up on cfe-dev I have decided that it would be best to allow the use of `<atomic>` in C++03. Although static initialization is a concern the syntax required to get it is C++11 only. Meaning that C++11 constant static initialization cannot silently break in C++03, it will always cause a syntax error. Furthermore `ATOMIC_VAR_INIT` and `ATOMIC_FLAG_INIT` remain defined in C++03 even though they cannot be used because C++03 usages will cause better error messages.
The main change in this patch is to replace `__has_feature(cxx_atomic)`, which only returns true when C++ >= 11, to `__has_extension(c_atomic)` which returns true whenever clang supports the required atomic builtins.
This patch adds the following macros:
* `_LIBCPP_HAS_C_ATOMIC_IMP` - Defined on clang versions which provide the C `_Atomic` keyword.
* `_LIBCPP_HAS_GCC_ATOMIC_IMP` - Defined on GCC > 4.7. We must use the fallback atomic implementation.
* `_LIBCPP_HAS_NO_ATOMIC_HEADER` - Defined when it is not safe to include `<atomic>`.
`_LIBCPP_HAS_C_ATOMIC_IMP` and `_LIBCPP_HAS_GCC_ATOMIC_IMP` are mutually exclusive, only one should be defined. If neither is defined then `<atomic>` is not implemented and including `<atomic>` will issue an error.
Reviewers: chandlerc, jroelofs, mclow.lists
Subscribers: cfe-commits
Differential Revision: http://reviews.llvm.org/D11555
llvm-svn: 245463
Summary:
Throughout the libc++ headers, there are a few instances where
_VSTD::move() is used to return a local variable. Howard commented in
r189039 that these were there "for non-obvious reasons such as to help
things limp along in C++03 language mode".
However, when compiling these headers with warnings on, and in C++11 or
higher mode (like we do in FreeBSD), they cause the following complaints
about pessimizing moves:
In file included from tests.cpp:26:
In file included from tests.hpp:29:
/usr/include/c++/v1/map:1368:12: error: moving a local object in a return statement prevents copy elision [-Werror,-Wpessimizing-move]
return _VSTD::move(__h); // explicitly moved for C++03
^
/usr/include/c++/v1/__config:368:15: note: expanded from macro '_VSTD'
#define _VSTD std::_LIBCPP_NAMESPACE
^
Attempt to fix this by adding a _LIBCPP_EXPLICIT_MOVE() macro to
__config, which gets defined to _VSTD::move for pre-C++11, and to
nothing for C++11 and later.
I am not completely satisfied with the macro name (I also considered
_LIBCPP_COMPAT_MOVE and some other variants), so suggestions are
welcome. :)
Reviewers: mclow.lists, howard.hinnant, EricWF
Subscribers: arthur.j.odwyer, cfe-commits
Differential Revision: http://reviews.llvm.org/D11394
llvm-svn: 245421
One of the aspects of CloudABI is that it aims to help you write code
that is thread-safe out of the box. This is very important if you want
to write libraries that are easy to reuse. For CloudABI we decided to
not provide the thread-unsafe functions. So far this is working out
pretty well, as thread-unsafety issues are detected really early on.
The following patch adds a knob to libc++,
_LIBCPP_HAS_NO_THREAD_UNSAFE_C_FUNCTIONS, that can be set to disable
thread-unsafe functions that can easily be avoided in practice. The
following functions are not thread-safe:
- <clocale>: locale handles should be preferred over setlocale().
- <cstdlib>: mbrlen(), mbrtowc() and wcrtomb() should be preferred over
their non-restartable counterparts.
- <ctime>: asctime(), ctime(), gmtime() and localtime() are not
thread-safe. The first two are also deprecated by POSIX.
Differential Revision: http://reviews.llvm.org/D8703
Reviewed by: marshall
llvm-svn: 240527
Summary: Currently we only enable the use of __is_final(...) with Clang. GCC also provides __is_final(...) since 4.7 in all standard modes. This patch creates the macro _LIBCPP_HAS_IS_FINAL to note the availability of `__is_final`.
Reviewers: danalbert, mclow.lists
Reviewed By: mclow.lists
Subscribers: cfe-commits
Differential Revision: http://reviews.llvm.org/D8795
llvm-svn: 239664
Summary:
Both clang and GCC provide C++11 decltype semantics as __decltype in c++03 mode. We should use this instead of __typeof__ when availble.
GCC added __decltype in 4.6.0, and AFAIK clang provided __decltype ever since 3.3. Unfortunately `__has_builtin(__decltype)` doesn't work for clang so we need to check the compiler version instead.
Reviewers: mclow.lists
Reviewed By: mclow.lists
Subscribers: cfe-commits
Differential Revision: http://reviews.llvm.org/D10426
llvm-svn: 239662
Until GCC 5.1 the __is_trivially* intrinsics were not provided. Enable use of
the builtins for GCC 5.1.
Also enable Reference qualified member functions for GCC 4.9 and greater.
This patch also defines _GNUC_VER to 0 when __GNUC__ is not defined because
libc++ assumes _GNUC_VER is always defined.
llvm-svn: 239653
The idea behind Nuxi CloudABI is that it is targeted at (but not limited to)
running networked services in a sandboxed environment. The model behind stdin,
stdout and stderr is strongly focused on interactive tools in a command shell.
CloudABI does not support the notion of stdin and stdout, as 'standard
input/output' does not apply to services. The concept of stderr does makes
sense though, as services do need some mechanism to log error messages in a
uniform way.
This patch extends libc++ in such a way that std::cin and std::cout and the
associated <cstdio>/<cwchar> functions can be disabled through the flags
_LIBCPP_HAS_NO_STDIN and _LIBCPP_HAS_NO_STDOUT, respectively. At the same time
it attempts to clean up src/iostream.cpp a bit. Instead of using a single array
of mbstate_t objects and hardcoding the array indices, it creates separate
objects that declared next to the iostream objects and their buffers. The code
is also restructured by interleaving the construction and setup of c* and wc*
objects. That way it is more obvious that this is done identically.
The c* and wc* objects already have separate unit tests. Make use of this fact
by adding XFAILs in case libcpp-has-no-std* is set. That way the tests work in
both directions. If stdin or stdout is disabled, these tests will therefore
test for the absence of c* and wc*.
Differential Revision: http://reviews.llvm.org/D8340
llvm-svn: 233275
Systems like FreeBSD's Capsicum and Nuxi CloudABI apply the concept of
capability-based security on the way processes can interact with the
filesystem API. It is no longer possible to interact with the VFS
through calls like open(), unlink(), rename(), etc. Instead, processes
are only allowed to interact with files and directories to which they
have been granted access. The *at() functions can be used for this
purpose.
This change adds a new config switch called
_LIBCPP_HAS_NO_GLOBAL_FILESYSTEM_NAMESPACE. If set, all functionality
that requires the global filesystem namespace will be disabled. More
concretely:
- fstream's open() function will be removed.
- cstdio will no longer pull in fopen(), rename(), etc.
- The test suite's get_temp_file_name() will be removed. This will cause
all tests that use the global filesystem namespace to break, but will
at least make all the other tests run (as get_temp_file_name will not
build anyway).
It is important to mention that this change will make fstream rather
useless on those systems for now. Still, I'd rather not have fstream
disabled entirely, as it is of course possible to come up with an
extension for fstream that would allow access to local filesystem
namespaces (e.g., by adding an openat() member function).
Differential revision: http://reviews.llvm.org/D8194
Reviewed by: jroelofs (thanks!)
llvm-svn: 232049
On a new platform that I am working on
(https://github.com/NuxiNL/cloudlibc) I am not implementing the
cat{open,close,gets}() API, just like Android, Newlib, etc.
Instead of adding yet another operating system name to the #ifs,
introduce _LIBCPP_HAS_CATOPEN in include/__config. Also adjust the code
to only pull in nl_types.h when _LIBCPP_HAS_CATOPEN is set. We only
needed this header for the cat*() API.
Differential Revision: http://reviews.llvm.org/D8163
Reviewed by: marshall
llvm-svn: 231937
CloudABI provides the _l() functions that are part of POSIX.1-2008, but
also the extensions that are available on systems like OS X and *BSD
(scanf_l, printf_l, etc).
llvm-svn: 231777
Nuxi CloudABI (https://github.com/NuxiNL/cloudlibc) does not allow
processes to access the global filesystem namespace. This breaks
random_device, as it attempts to use /dev/{u,}random. This change adds
support for arc4random(), which is present on CloudABI.
In my opinion it would also make sense to use arc4random() on other
operating systems, such as *BSD and Mac OS X, but I'd rather leave that
to the maintainers of the respective platforms. Switching to
arc4random() does change the ABI.
This change also attempts to make some cleanups to the code. It adds a
single #define for every random interface, instead of testing against
operating systems explicitly.
As discussed, also validate the token argument to be equal to
"/dev/urandom" on all systems that only provide pseudo-random numbers.
This should cause little to no breakage, as "/dev/urandom" is also the
default argument value.
Reviewed by: jfb
Differential Revision: http://reviews.llvm.org/D8134
llvm-svn: 231764
Add a new _LIBCPP_UNUSED define in __config, which can be used to
indicate explicitly unused items, and apply it to the __imp__ field of
__libcpp_refstring.
Somebody who knows about Microsoft C++ and IBM C++ should fill in the
unused attribute syntax appropriate for those compilers, if there is
any.
Differential Revision: http://reviews.llvm.org/D6836
llvm-svn: 228281
Summary:
The NaCl sandbox doesn't allow opening files under /dev, but it offers an API which provides the same capabilities. This is the same random device emulation that nacl_io performs for POSIX support, but nacl_io is an optional library so libc++ can't assume that device emulation will be performed. Note that NaCl only supports /dev/urandom, not /dev/random.
This patch also cleans up some of the preprocessor #endif, and fixes the test for Win32 (it accepts any token, and would therefore never throw regardless of the token provided).
Test Plan: ninja check-libcxx
Reviewers: dschuff, mclow.lists, danalbert
Subscribers: jfb, cfe-commits
Differential Revision: http://reviews.llvm.org/D6442
llvm-svn: 223068
Summary: This fixes ODR violations in C++03 mode in test/localization/locale.stdcvt. The special case for linux was introduced in 2010 before clang always defined __char16_t and __char32_t.
Reviewers: mclow.lists, danalbert, jroelofs, EricWF
Reviewed By: EricWF
Subscribers: cfe-commits
Differential Revision: http://reviews.llvm.org/D5930
llvm-svn: 220716