This patch gets rid of technical debt around std::pointer_safety which,
I claim, is entirely unnecessary. I don't think anybody has used
std::pointer_safety in actual code because we do not implement the
underlying garbage collection support. In fact, P2186 even proposes
removing these facilities entirely from a future C++ version. As such,
I think it's entirely fine to get rid of complex workarounds whose goals
were to avoid breaking the ABI back in 2017.
I'm putting this up both to get reviews and to discuss this proposal for
a breaking change. I think we should be comfortable with making these
tiny breaks if we are confident they won't hurt anyone, which I'm fairly
confident is the case here.
Differential Revision: https://reviews.llvm.org/D100410
This is the first step at implementing <format>. It adds the <format> header
and implements the `format_error`. class.
Implemnts parts of:
-P0645 Text Formatting
Reviewed By: ldionne, #libc, miscco, curdeius
Differential Revision: https://reviews.llvm.org/D92214
By encoding ABI-affecting properties in the name of the ABI list, it
makes it clear when an ABI list test should or should not be available,
and what results we should expect.
Note that we clearly don't encode all ABI-affecting parameters in the
name right now -- I just ported over what we supported in the code that
was there previously. As we encounter configurations that we wish to
support but produce different ABI lists, we can add those to the ABI
identifier and start supporting them.
This commit also starts checking the ABI list in the CI jobs that run
a supported configuration. Eventually, all configurations should have
a generated ABI list and the test should even run implicitly as part of
the Lit test suite.
Differential Revision: https://reviews.llvm.org/D92194
We don't actually update the ABI lists at every release -- it's too much
work, since we'd technically have to do it even for minor releases.
Furthermore, I don't think anybody uses those (I certainly don't rely
on them for anything).
Instead, it is better to rely on the ABI list changelog and the canonical
ABI list that we always keep up to date. If one wants to know what symbols
were shipped in a specific release, that can be discovered easily using
Git, which is a superior tool than keeping textual copies of old versions.
The `posix_memalign@GLIBC_2.2.5` symbol can't have been added by r284206,
because it doesn't show up in the corresponding ABI list. It's also not
defined in libc++, so that wouldn't make sense. It must have made it into
that comment by mistake.
This commit adds new explicit instantiations for some classes in <iostream>
in the library. This is done after noticing that many programs that use
streams end up containing weak definitions of these classes, which has a
negative impact on both code size and load times (due to the need to
resolve weak symbols at load time). Note that we are just adding the
additional explicit instantiations for the `char` specializations, since
the `wchar_t` specializations are not used as often, and as a result there
wouldn't be a clear benefit.
This change is not an ABI break, since we are just adding additional
symbols.
Differential Revision: https://reviews.llvm.org/D90677
Instead of having to remember the command-line to use every time, this
commit adds a CMake target to generate the ABI list in the current
configuration, if it is supported.
As a fly-by change, remove scripts that are now unused (sym_match.py
and sym_extract.py).
Previously, we would define new/delete in both libc++ and libc++abi.
Not only does this cause code bloat, but also it's technically an ODR
violation since we don't know which operator will be selected. Furthermore,
since those are weak definitions, we should strive to have as few of them
as possible (to improve load times).
My preferred choice would have been to put the operators in libc++ only
by default, however that would create a circular dependency between
libc++ and libc++abi, which GNU linkers don't handle.
Folks who want to ship new/delete in libc++ instead of libc++abi are
free to do so by turning on LIBCXX_ENABLE_NEW_DELETE_DEFINITIONS at
CMake configure time.
On Apple platforms, this shouldn't be an ABI break because we re-export
the new/delete symbols from libc++abi. This change actually makes libc++
behave closer to the system libc++ shipped on Apple platforms.
On other platforms, this is an ABI break for people linking against libc++
but not libc++abi. However, vendors have been consulted in D68269 and no
objection was raised. Furthermore, the definitions can be controlled to
appear in libc++ instead with the CMake option.
Differential Revision: https://reviews.llvm.org/D68269
This reverts commit c7d4aa711a. I am still investigating the issue,
but it looks like that commit has an interaction with ld64 that causes
new/delete weak re-exports not to work properly anymore. This is weird
because this commit did not touch the exports of new/delete -- I am
still investigating.
Instead of managing two copies of the symbol lists, reuse the same list
in libc++abi and libc++.
Differential Revision: https://reviews.llvm.org/D88623
We previously tried re-exporting symbols that didn't exist when
exceptions were disabled. Note that building libc++abi without
exceptions still doesn't work when linking against the default-provided
libSystem.dylib, because it transitively depends on libobjc.dylib,
and that requires __gxx_personality_v0. But building libc++abi
with exceptions and libc++ without exceptions does work.
- Avoid using C++11-and-later features in <atomic>:
Historically, we've supported <atomic> in C++03, so we can't use C++11
features in that header. This is something we really need to change,
since our implementation of <atomic> is starting to accumulate technical
debt because of that.
- Mark a test as unsupported on single threaded systems
- Add missing symbols to the Linux ABI list
- Add the new symbols to the ABI list on Darwin
- Add XFAIL markup to the tests that require dylib support on older platforms
- Add availability markup for back-deployment
This addresses the longstanding FIXME and makes libc++ build more
similar to other runtimes.
Differential Revision: https://reviews.llvm.org/D61275
llvm-svn: 359656
Summary:
Instead of populating the global LIBCXX_LIBRARIES, we use the link-time
dependency management built into CMake to propagate link flags. This
leads to a cleaner and easier-to-follow build.
Reviewers: phosek, smeenai, EricWF
Subscribers: mgorny, christof, jkorous, dexonsmith, jfb, mstorsjo, libcxx-commits
Tags: #libc
Differential Revision: https://reviews.llvm.org/D60969
llvm-svn: 359571
libc++ ABI v1 provides three valarray symbols as part of the shared library:
valarray<size_t>::valarray(size_t)
valarray<size_t>::~valarray()
valarray<size_t>::resize(size_t, size_t)
The first two of these are intended to be removed in V2 of the ABI: they're
attributed _LIBCPP_HIDE_FROM_ABI_AFTER_V1, and it appears that the intention
is that these symbols from the library are not used even when building using
the V1 ABI. However, there are explicit instantiation declarations for all
three symbols in the header, which are not correct as we do not intend to find
an instantiation of these functions that is provided elsewhere.
(A recent change to clang to properly diagnose explicit instantiation
declarations of internal linkage functions -- required by [temp.explicit]p13 --
had to be rolled back because it diagnosed these explicit instantiations.)
Remove the explicit instantiation declarations, and remove the explicit
instantiation definitions for V2 of the libc++ ABI onwards.
llvm-svn: 359243
This enables the use of this script from other build systems like
GN which don't support post-build actions as well as for static
archives.
Differential Revision: https://reviews.llvm.org/D60309
llvm-svn: 358915
Summary:
Ensure we re-export __cxa_throw_bad_array_new_length and
__cxa_uncaught_exceptions from libc++, since they are now
provided by libc++abi.
Doing this allows us to stop linking explicitly against libc++abi in
the libc++abi tests, since libc++ re-exports all the necessary symbols.
However, there is one caveat to that. We don't want libc++ to re-export
__cxa_uncaught_exception (the singular form), since it's only provided
for backwards compatibility. Hence, for the single test where we check
this backwards compatibility, we explicitly link against libc++abi.
PR27405
PR22654
Reviewers: EricWF
Subscribers: christof, jkorous, dexonsmith, libcxx-commits
Tags: #libc
Differential Revision: https://reviews.llvm.org/D60424
llvm-svn: 358690
Some linker libraries are only needed for shared libc++, some only
for static libc++, combining these together in LIBCXX_LIBRARIES and
LIBCXX_INTERFACE_LIBRARIES can introduce unnecessary dependencies.
This changes splits those up into LIBCXX_SHARED_LIBRARIES and
LIBCXX_STATIC_LIBRARIES matching what libc++abi already does.
Differential Revision: https://reviews.llvm.org/D57872
llvm-svn: 358614
In this case, CMake doesn't know about the c++abi target within the
same CMake run.
This reverts this aspect back to how it was before SVN r357811.
Differential Revision: https://reviews.llvm.org/D60448
llvm-svn: 358009
CMake already specifies those, and we never actually want those to be
used. In fact, r357811 re-ordered those flags in a way that the
explicitly-provided install_name was overriding the CMake-provided
install_name (instead of the other way around). This caused the dylib
to be considered a system dylib, and hence the explicitly provided rpath
to be ignored. This, in turn, caused some unit tests to start linking
against the system libc++.dylib instead of the freshly-built one.
Specifically, the unit tests that started linking against the system
dylib are those that didn't specify a DYLD_LIBRARY_PATH, such as
last_write_time.sh.cpp.
llvm-svn: 357946
The refactoring in r357811 made it so that we didn't add the ABI library
to the list of LIBCXX_LIBRARIES. As a result, benchmarks didn't link to
the ABI library and were missing symbols. This broke the build bots.
As a drive-by fix, we also provide the SHARED ABI library to the linker
script instead of the STATIC ABI library.
This couldn't be discovered on Apple platforms because libc++.dylib
re-exports libc++abi.dylib symbols there.
llvm-svn: 357818
Summary:
There's a lot of CMake logic that's only relevant to the shared library,
yet it was using a code path and setting variables that impact both the
shared and the static libraries. This patch moves this logic so that it
clearly only impacts the shared library.
Reviewers: phosek, smeenai, EricWF
Subscribers: mgorny, christof, jkorous, dexonsmith, libcxx-commits
Tags: #libc
Differential Revision: https://reviews.llvm.org/D60276
llvm-svn: 357811
This addresses the issue introduced in r354212 which broke the case when
static libc++abi is merged into static libc++, but shared libc++ is
linked against shared libc++. There are 4 different possible
combinations which is difficult to capture using a single variable. This
change splits LIBCXX_CXX_ABI_LIBRARY into two:
LIBCXX_CXX_SHARED_ABI_LIBRARY and LIBCXX_CXX_STATIC_ABI_LIBRARY to
handle the shared and static cases. This in turn allows simplification
of some of the logic around merging of static archives.
Differential Revision: https://reviews.llvm.org/D60114
llvm-svn: 357556
Summary:
I can't see a good reason to disallow this, even though it isn't the
standard way we build libc++ for Apple platforms.
Making this work on Apple platforms requires using different flags for
--whole-archive and removing the -D flag when running `ar` to merge
archives because that flag isn't supported by the `ar` shipped on Apple
platforms. This shouldn't be an issue since the -D option appears to be
enabled by default in GNU `ar`.
Reviewers: phosek, EricWF, serge-sans-paille
Subscribers: mgorny, christof, jkorous, dexonsmith, libcxx-commits
Differential Revision: https://reviews.llvm.org/D59513
llvm-svn: 356903
When libc++ does not provide new/delete, libc++abi now also provides the
aligned allocation and deallocation functions, so those should be part of
the re-export list for libc++.
llvm-svn: 356804
Summary: Filesystem doesn't work on Windows, so we need a mechanism to turn it off for the time being.
Reviewers: ldionne, serge-sans-paille, EricWF
Reviewed By: EricWF
Subscribers: mstorsjo, mgorny, christof, jdoerfert, libcxx-commits
Differential Revision: https://reviews.llvm.org/D59619
llvm-svn: 356633
Summary:
This change allows specifying the version of libc++abi's ABI to re-export
when configuring CMake. It also clearly identifies which ABI version of
libc++abi each export file contains.
Finally, it removes hardcoded knowledge about the 10.9 SDK for MacOS,
since that knowledge is not relevant anymore. Indeed, libc++ can't be
built with the toolchain that came with the 10.9 SDK anyway because
the version of Clang it includes is too old (for example if you want
to build a working libc++.dylib, you need bugfixes to visibility
attributes that are only in recent Clangs).
Reviewers: dexonsmith, EricWF
Subscribers: mgorny, christof, jkorous, arphaman, libcxx-commits
Differential Revision: https://reviews.llvm.org/D59489
llvm-svn: 356587
Summary:
This patch treats <filesystem> as a first-class citizen of the dylib,
like all other sub-libraries (e.g. <chrono>). As such, it also removes
all special handling for installing the filesystem library separately
or disabling part of the test suite from the lit command line.
Unlike the previous attempt (r356500), this doesn't remove all the
filesystem tests.
Reviewers: mclow.lists, EricWF, serge-sans-paille
Subscribers: mgorny, christof, jkorous, dexonsmith, jfb, jdoerfert, libcxx-commits
Differential Revision: https://reviews.llvm.org/D59152
llvm-svn: 356518
When I applied r356500 (https://reviews.llvm.org/D59152), I somehow
deleted all of filesystem's tests. I will revert r356500 and re-apply
it properly.
llvm-svn: 356505
Summary:
This patch treats <filesystem> as a first-class citizen of the dylib,
like all other sub-libraries (e.g. <chrono>). As such, it also removes
all special handling for installing the filesystem library separately
or disabling part of the test suite from the lit command line.
Reviewers: mclow.lists, EricWF, serge-sans-paille
Subscribers: mgorny, christof, jkorous, dexonsmith, jfb, jdoerfert, libcxx-commits
Differential Revision: https://reviews.llvm.org/D59152
llvm-svn: 356500
Summary:
The reason libc++ implemented a throwing debug mode handler was for ease of testing. Specifically,
I thought that if a debug violation aborted, we could only test one violation per file. This made
it impossible to test debug mode. Which throwing behavior we could test more!
However, the throwing approach didn't work either, since there are debug violations underneath noexcept
functions. This lead to the introduction of `_NOEXCEPT_DEBUG`, which was only noexcept when debug
mode was off.
Having thought more and having grown wiser, `_NOEXCEPT_DEBUG` was a horrible decision. It was
viral, it didn't cover all the cases it needed to, and it was observable to the user -- at worst
changing the behavior of their program.
This patch removes the throwing debug handler, and rewrites the debug tests using 'fork-ing' style
death tests.
Reviewers: mclow.lists, ldionne, thomasanderson
Reviewed By: ldionne
Subscribers: christof, arphaman, libcxx-commits, #libc
Differential Revision: https://reviews.llvm.org/D59166
llvm-svn: 356417
CMake will define -Dcxx_shared_EXPORTS when building the shared library
by default. In theory, this is used to signal to the library that we're
building a shared library and that dllimport/dllexport should be used.
However, we already have our own way of doing that, so I'm removing this
define to avoid meaningless command line arguments in the build.
llvm-svn: 356167
