The Itanium C++ ABI specifies that FP literals are encoded using a
lowercase hexadecimal string. Previously, libc++abi allowed uppercase
A-F characters but decoded them by subtracting 'a' from them, producing
negative digit values. It is especially confusing to accept an 'E' digit
because 'E' marks the end of the FP literal.
Previously, the list of libc++abi symbols that we re-export from libc++
would be partly encoded in libc++abi (and re-exported automatically via
the cxxabi-reexports target), and partly hard-coded in
libcxx/lib/libc++abi.exp. The duplication of information led to symbols
not being exported from libc++ after being added to libc++abi when they
should have been.
This patch removes the duplication of information. After this patch, the
full list of symbols to re-export from libc++abi is handled by the
cxxabi-reexports target and is stored in libcxxabi.
The symbols newly re-exported from libc++ are mainly new fundamental
typeinfos and a bunch of functions and classes that are part of
libc++abi but are most likely implementation details. In the future, it
would be possible to try to trim down the set of what we export from
libc++abi (and hence what we re-export from libc++) to remove some
implementation detail symbols.
Fixes#79008
Chrome rolls libc++ and libc++abi as separate projects. As a result, they
may not always be updated in lockstep, and this can lead to build failures
when mixing libc++ that doesn't have <__thread/support.h> with libc++abi
that requires it.
This patch adds a workaround to make libc++abi work with both versions.
While Chrome's setup is not supported, this workaround will allow them
to go back to green and do the required work needed to roll libc++ and
libc++abi in lockstep. This workaround will be short-lived -- I have a
reminder to go back and remove it by EOW.
The <__threading_support> header is a huge beast and it's really
difficult to navigate. I find myself struggling to find what I want
every time I have to open it, and I've been considering splitting it up
for years for that reason.
This patch aims not to contain any functional change. The various
implementations of the threading base are simply moved to separate
headers and then the individual headers are simplified in mechanical
ways. For example, we used to have redundant declarations of all the
functions at the top of `__threading_support`, and those are removed
since they are not needed anymore. The various #ifdefs are also
simplified and removed when they become unnecessary.
Finally, this patch adds documentation for the API we expect from any
threading implementation.
This addresses cases (currently failing) where we throw a null
pointer-to-object and fixes#64953.
We are trying to satisfy the following bullet from the C++ ABI 15.3:
* the handler is of type cv1 T* cv2 and E is a pointer type that can be
converted to the type of the handler by either or both of:
- a standard pointer conversion (4.10 [conv.ptr]) not involving
conversions to private or protected or ambiguous classes.
- a qualification conversion.
The existing implementation assesses the ambiguity of bases by computing
the offsets to them; ambiguous cases are then when the same base appears
at different offsets. The computation of offset includes indirecting
through the vtables to find the offsets to virtual bases.
When the thrown pointer points to a real object, this is quite efficient
since, if the base is found, and it is not ambiguous and on a public
path, the offset is needed to return the adjusted pointer (and the
indirections are not particularly expensive to compute).
However, when we throw a null pointer-to-object, this scheme is no
longer applicable (and the code currently bypasses the relevant
computations, leading to the incorrect catches reported in the issue).
-----
The solution proposed here takes a composite approach:
1. When the pointer-to-object points to a real instance (well, at least,
it is determined to be non-null), we use the existing scheme.
2. When the pointer-to-object is null:
* We note that there is no real object.
* When we are processing non-virtual bases, we continue to compute the
offsets, but for a notional dummy object based at 0. This is OK, since
we never need to access the object content for non-virtual bases.
* When we are processing a path with one or more virtual bases, we
remember a cookie corresponding to the inner-most virtual base found so
far (and set the notional offset to 0). Offsets to inner non-virtual
bases are then computed as normal.
A base is then ambiguous iff:
* There is a recorded virtual base cookie and that is different from the
current one or,
* The non-virtual base offsets differ.
When a handler for a pointer succeeds in catching a base pointer for a
thrown null pointer-to-object, we still return a nullptr (so the
adjustment to the pointer is not required and need not be computed).
Since we noted that there was no object when starting the search for
ambiguous bases, we know that we can skip the pointer adjustment.
This was originally uploaded as https://reviews.llvm.org/D158769.
Fixes#64953
When lpStartEncoding is different from DW_EH_PE_omit, lpStart can be set
to zero which is a valid base address for landing pads. Such base value
is useful when landing pads are placed in different sections.
Fixes#72582.
This patch actually runs the tests for picolibc behind an emulator,
removing a few workarounds and increasing coverage.
Differential Revision: https://reviews.llvm.org/D155521
Picolibc is a C Standard Library that is commonly used in embedded
environments. This patch adds initial support for this configuration
along with pre-commit CI. As of this patch, the test suite only builds
the tests and nothing is run. A follow-up patch will make the test suite
actually run the tests.
Differential Revision: https://reviews.llvm.org/D154246
The mangling for an explicitly named object was introduced in
https://reviews.llvm.org/D140828
See following discussion for why a new mangling had to be introduced:
https://github.com/itanium-cxx-abi/cxx-abi/issues/148
Since clang started emitting names with the new mangling, this patch
implements support for demangling such names.
The approach this patch takes is to add a new `ExplicitObjectParameter`
node that will print the first parameter of a function declaration with
a `this ` prefix, to reflect what was spelled out in source.
Example:
```
void MyClass::func(this MyClass const& self); // _ZNH7MyClass4funcERKS_
```
With this patch, the above demangles to:
```
_ZNH7MyClass4funcERKS_ -> MyClass::func(this MyClass const&)
```
Note that `func` is not marked as `const &`, since the
function-qualifiers are now encoded as part of the explicit `this`. C++
doesn't allow specifying the function-qualifiers in the presence of an
explicit object parameter, so this demangling is consistent with the
source spelling.
Adding test-cases to the `cases` array causes `git clang-format` to
split the strings of many of the existing test-cases, making them harder
to read/work with in most cases.
This patch disables `clang-format` for the `cases` array so it doesn't
catch anyone off-guard in the future.
The runtimes now have a principled way of doing assertions in relation
to hardening, so we should use that instead of raw calls to assert()
inside libc++abi. This patch aims to maintain the behavior of the
demangler code when it is used from within LLVM by introducing a simple
DEMANGLE_ASSERT(...) macro that is then defined to the appropriate
assertion mechanism.
This will allow for configuring tests according to AIX version.
Reviewed By: daltenty, #libc, Mordante
Differential Revision: https://reviews.llvm.org/D149660
Mark tests as necessary to accommodate Android L (5.0 / API 21) and up.
Add three Android lit features:
- android
- android-device-api=(21,22,23,...)
- LIBCXX-ANDROID-FIXME (for failures that need follow-up work)
Enable an AIX workaround in filesystem_test_helper.h for the broken
chmod on older Android devices.
Mark failing test with XFAIL or UNSUPPORTED:
- Mark modules tests as UNSUPPORTED, matching other configurations.
- Mark a gdb test as UNSUPPORTED.
- XFAIL tests for old devices that lack an API (fmemopen).
- XFAIL various FS tests (because SELinux blocks FIFO and hard linking,
because fchmodat is broken on old devices).
- XFAIL various locale tests (because Bionic has limited locale
support). (Also XFAIL an re.traits test.)
- XFAIL some print.fun tests because the error exception has no system
error string.
- Mark std::{cin,wcin} tests UNSUPPORTED because they hang with
adb_run.py on old devices.
- Mark a few tests UNSUPPORTED because they allocate too much memory.
- notify_one.pass.cpp is flaky on Android.
- XFAIL libc++abi demangler test because of Android's special long
double on x86[-64].
N.B. The `__ANDROID_API__` macro specifies a minimum required API level
at build-time, whereas the android-device-api lit feature is the
detected API level of the device at run-time. The android-device-api
value will be >= `__ANDROID_API__`.
This commit was split out from https://reviews.llvm.org/D139147.
Fixes: https://github.com/llvm/llvm-project/issues/69270
I could probably break this commit into more pieces.
---
This patch adds libc++ support for Android L (Android 5.0+) and up,
tested using the Android team's current compiler, a recent version of
the AOSP sysroot, and the x86[-64] Android Emulator.
CMake and Lit Configuration:
Add runtimes/cmake/android/Arch-${ARCH}.cmake files that configure CMake
to cross-compile to Android without using CMake's built-in NDK support
(which only works with an actual packaged NDK).
Add libcxx/cmake/caches/AndroidNDK.cmake that builds and tests libc++
(and libc++abi) for Android. This file configures libc++ to match what
the NDK distributes, e.g.:
- libc++_shared.so (includes libc++abi objects, there is no
libc++abi.so). libunwind is linked statically but not exported.
- libc++_static.a (does not include libc++abi) and libc++abi.a
- `std::__ndk1` namespace
- All the libraries are built with `__ANDROID_API__=21`, even when they
are linked to something targeting a higher API level.
(However, when the Android LLVM team builds these components, they do
not use these CMake cache files. Instead they use Python scripts to
configure the builds. See
https://android.googlesource.com/toolchain/llvm_android/.)
Add llvm-libc++[abi].android-ndk.cfg.in files that test the Android
NDK's libc++_shared.so. These files can target old or new Android
devices. The Android LLVM team uses these test files to test libc++ for
both arm/arm64 and x86/x86_64 architectures.
The Android testing mode works by setting %{executor} to adb_run.py,
which uses `adb push` and `adb shell` to run tests remotely. adb_run.py
always runs tests as the "shell" user even on an old emulator where "adb
unroot" doesn't work. The script has workarounds for old Android
devices. The script uses a Unix domain socket on the host
(--job-limit-socket) to restrict concurrent adb invocations. Compiling
the tests is a major part of libc++ testing run-time, so it's desirable
to exploit all the host cores without overburdening the test devices,
which can have far fewer cores.
BuildKite CI:
Add a builder to run-buildbot, `android-ndk-*`, that uses Android Clang
and an Android sysroot to build libc++, then starts an Android emulator
container to run tests.
Run the emulator and an adb server in a separate Docker container
(libcxx-ci-android-emulator), and create a separate Docker image for
each emulator OS system image. Set ADB_SERVER_SOCKET to connect to the
container's adb server. Running the only adb server inside the container
makes cleanup more reliable between test runs, e.g. the adb client
doesn't create a `~/.android` directory and the adb server can be
restarted along with the emulator using docker stop/run. (N.B. The
emulator insists on connecting to an adb server and will start one
itself if it can't connect to one.)
The suffix to the android-ndk-* job is a label that concisely specifies
an Android SDK emulator image. e.g.:
- "system-images;android-21;default;x86" ==> 21-def-x86
- "system-images;android-33;google_apis;x86_64" ==> 33-goog-x86_64
Fixes: https://github.com/llvm/llvm-project/issues/69270
Differential Revision: https://reviews.llvm.org/D139147
Since 78d649a417 the recommended way to
pass an executor is to use the _TEST_PARAMS variable, which means we now
pass more complicated value (including ones that may contain multiple
`=`) as part of this variable. However, the `REGEX REPLACE` being used
has greedy matches so everything up to the last = becomes part of the
variable name which results in invalid syntax in the generated lit
config file.
This was noticed due to builder failures for those using the
CrossWinToARMLinux.cmake cache file.
---------
Co-authored-by: Vladimir Vereschaka <vvereschaka@accesssoftek.com>
This is useful when trying to run multiple tests with different
arguments to the executor script. This is needed in my case since I
do not know the correct ssh connection arguments when building libc++.
The testing script I have spawns multiple QEMU instances that listen on
a given port on localhost and runs lit with the --num-shards/--run-shard
argument. In order to connect each shard to the right QEMU instances I
need to customize the arguments passed to ssh.py (--extra-ssh-args and
--extra-scp-args) but can't do this at configure time since the target
port is only known when running the tests but not when calling CMake.
This change allows me to pass `executor=ssh.py <args>` to lit once I
know
the right hostname/port for running the tests.
This also deprecates the `LIB{CXX,CXXABI,UNWIND}_EXECUTOR` CMake
variable
as the same can be achieved by adding `executor=...` to the
`LIB{CXX,CXXABI,UNWIND}_TEST_PARAMS` variable.
Since GCC now supports -nostdlib++, we can remove some complexity in the
test configurations and do the same as Clang. However, we can't fully
remove the GCC test configuration for libc++ because we apparently need
to explicitly link against libm for some tests to work.
This implements proposals from:
- https://github.com/itanium-cxx-abi/cxx-abi/issues/24: mangling for
constraints, requires-clauses, requires-expressions.
- https://github.com/itanium-cxx-abi/cxx-abi/issues/31: requires-clauses and
template parameters in a lambda expression are mangled into the <lambda-sig>.
- https://github.com/itanium-cxx-abi/cxx-abi/issues/47 (STEP 3): mangling for
template argument is prefixed by mangling of template parameter declaration
if it's not "obvious", for example because the template parameter is
constrained (we already implemented STEP 1 and STEP 2).
This changes the manglings for a few cases:
- Functions and function templates with constraints.
- Function templates with template parameters with deduced types:
`typename<auto N> void f();`
- Function templates with template template parameters where the argument has a
different template-head:
`template<template<typename...T>> void f(); f<std::vector>();`
In each case where a mangling changed, the change fixes a mangling collision.
Note that only function templates are affected, not class templates or variable
templates, and only new constructs (template parameters with deduced types,
constrained templates) and esoteric constructs (templates with template
template parameters with non-matching template template arguments, most of
which Clang still does not accept by default due to
`-frelaxed-template-template-args` not being enabled by default), so the risk
to ABI stability from this change is relatively low. Nonetheless,
`-fclang-abi-compat=17` can be used to restore the old manglings for cases
which we could successfully but incorrectly mangle before.
Fixes#48216, #49884, #61273
Reviewed By: erichkeane, #libc_abi
Differential Revision: https://reviews.llvm.org/D147655
Add UNSUPPORTED to pass tests on VE. VE uses SjLj libunwind, so
_Unwind_Backtrace and _Unwind_ForcedUnwind are not implemented.
Reviewed By: MaskRay, #libc_abi, ldionne
Differential Revision: https://reviews.llvm.org/D159446
I'm making a change in this area (https://reviews.llvm.org/D138461), so update the test:
* Add proper synchronization instead of a sleep.
* Avoid some unnecessary size_t casts.
* Spawn the number of hardware threads instead of 10.
* Check that `__cxa_get_globals` and `__cxa_get_globals_fast` return
the same values.
* Split the test in with-threads and without-threads tests to simplify
the code.
Differential Revision: https://reviews.llvm.org/D138460
Co-authored-by: Louis Dionne <ldionne.2@gmail.com>
This commit contains refactorings around __dynamic_cast without changing
its behavior. Some important changes include:
- Refactor __dynamic_cast into various small helper functions;
- Move dynamic_cast_stress.pass.cpp to libcxx/benchmarks and refactor
it into a benchmark. The benchmark performance numbers are updated
as well.
Differential Revision: https://reviews.llvm.org/D138006
Our threading support layer is currently a huge mess. There are too many
configurations with too many confusing names, and none of them are tested
in the usual CI. Here's a list of names related to these configurations:
LIBCXX_BUILD_EXTERNAL_THREAD_LIBRARY
_LIBCPP_BUILDING_THREAD_LIBRARY_EXTERNAL
LIBCXXABI_BUILD_EXTERNAL_THREAD_LIBRARY
_LIBCPP_HAS_THREAD_LIBRARY_EXTERNAL
LIBCXX_HAS_EXTERNAL_THREAD_API
_LIBCPP_HAS_THREAD_API_EXTERNAL
This patch cleans this up by removing the ability to build libc++ with
an "external" threading library for testing purposes, removing 4 out of
6 "names" above. That setting was meant to be used by libc++ developers,
but we don't use it in-tree and it's not part of our CI.
I know the ability to use an external threading API is used by some folks
out-of-tree, and this patch doesn't change that. This only changes the
way they will have to test their external threading support. After this
patch, the intent would be for them to set `-DLIBCXX_HAS_EXTERNAL_THREAD_API=ON`
when building the library, and to provide their usual `<__external_threading>`
header when they are testing the library. This can be done easily now
that we support custom lit configuration files in test suites.
The motivation for this patch is that our threading support layer is
basically unmaintainable -- anything beyond adding a new "backend" in
the slot designed for it requires incredible attention. The complexity
added by this setting just doesn't pull its weigh considering the
available alternatives.
Concretely, this will also allow future patches to clean up
`<__threading_support>` significantly.
Differential Revision: https://reviews.llvm.org/D154466
That is not necessary to test what we're testing, and in fact including
abort_message.cpp into that file caused some link errors if we didn't
link some of the dependencies of libc++abi directly into the test.
Differential Revision: https://reviews.llvm.org/D152862
unittest_demangle.pass.cpp uses the preprocessor to #include
cxa_demangle.cpp. D148566 will make more use of std::string_view in
libcxxabi rather than the home-grown StringView, but as a result of
D149092, a definition of abort_message needs to be provided.
Otherwise builds of check-cxxabi with -DLLVM_ENABLE_ASSERTIONS=ON will
fail to link with the errors:
/usr/bin/ld: /tmp/lit-tmp-0akcq37p/cc6DLdvw.o: in function `(anonymous namespace)::itanium_demangle::starts_with(std::__1::basic_string_view<char, std::__1::char_traits<char> >, char)':
unittest_demangle.pass.cpp:(.text+0x81): undefined reference to `abort_message'
/usr/bin/ld: /tmp/lit-tmp-0akcq37p/cc6DLdvw.o: in function `(anonymous namespace)::itanium_demangle::starts_with(std::__1::basic_string_view<char, std::__1::char_traits<char> >, std::__1::basic_string_view<char, std::__1::char_traits<char> >)':
unittest_demangle.pass.cpp:(.text+0x2aa): undefined reference to `abort_message'
/usr/bin/ld: unittest_demangle.pass.cpp:(.text+0x312): undefined reference to `abort_message'
/usr/bin/ld: /tmp/lit-tmp-0akcq37p/cc6DLdvw.o: in function `(anonymous namespace)::itanium_demangle::OutputBuffer::writeUnsigned(unsigned long, bool)':
unittest_demangle.pass.cpp:(.text+0x54f): undefined reference to `abort_message'
/usr/bin/ld: unittest_demangle.pass.cpp:(.text+0x5b7): undefined reference to `abort_message'
/usr/bin/ld: /tmp/lit-tmp-0akcq37p/cc6DLdvw.o:unittest_demangle.pass.cpp:(.text+0xe6e): more undefined references to `abort_message' follow
/usr/bin/ld: /home/libcxx-builder/.buildkite-agent/builds/google-libcxx-builder-f0560ea595b1-1/llvm-project/libcxx-ci/build/generic-gcc/test/Output/unittest_demangle.pass.cpp.dir/t.tmp.exe: hidden symbol `abort_message' isn't defined
Use the preprocessor further to provide the definition of abort_message
for this unittest.
Reviewed By: #libc_abi, phosek
Differential Revision: https://reviews.llvm.org/D151160
This is an ongoing series of commits that are reformatting our
Python code.
Reformatting is done with `black`.
If you end up having problems merging this commit because you
have made changes to a python file, the best way to handle that
is to run git checkout --ours <yourfile> and then reformat it
with black.
If you run into any problems, post to discourse about it and
we will try to help.
RFC Thread below:
https://discourse.llvm.org/t/rfc-document-and-standardize-python-code-style
Reviewed By: #libc, kwk, Mordante
Differential Revision: https://reviews.llvm.org/D150763
On Windows, the PATH env variable is used for locating dynamically
linked librarys, akin to LD_LIBRARY_PATH on Linux.
The tests that run with a dynamically linked libc++ used "--env
PATH=%{lib}" in the test config. This had the unfortunate side effect
of making other tools from PATH unavailable during the runtime of the
tests; in particular, it caused the "executor-has-no-bash" flag to be
set for all those Windows test configs (with the clang-cl static config
being the only one lacking it).
Thus, this increases the number of tests actually included in the
clang-cl dll and all mingw test configs by 9 tests.
The clang-cl static test configuration has been executing those tests
since the "--env PATH=%{lib}" was removed from that test config in
e78223e79e. (For mingw we haven't had a
need to split the test config between shared and static, which means
that the mingw static test config previously ran with --env PATH
needlessly.)
This increases the test coverage for patches like D146398 which
can't be executed in the executor-has-no-bash configs.
Change the default value of the arg.env to an empty array; when we do
pass values to the option, they get passed as an array of strings,
so make sure the variable behaves consistently when no arguments
have been passed.
Differential Revision: https://reviews.llvm.org/D148324
Don't link libc++abi separately in addition to the main -lc++; in
mingw build configs, libc++abi is always bundled into libc++
(via LIBCXX_ENABLE_STATIC_ABI_LIBRARY).
In the case of a shared linked libc++, linking a separate static
libc++abi leads to linker errors.
Differential Revision: https://reviews.llvm.org/D147638
With current versions of mingw-w64 headers, code following
assert(false) isn't considered unreachable - thus add a dummy
"return nullptr;", to avoid warnings (treated as errors) for a
missing return statement.
The root cause does get fixed further upstream in mingw-w64 in
1690994f51
though.
Differential Revision: https://reviews.llvm.org/D147860
Previously, all the output from the tests were placed directly in
the build directory. The tests produce a couple directories named
`__config_{exec,cache,src}__` which are easy to distinguish, and
the output from the individual tests were placed directly in a
directory named `Output`.
This is the same change as
736c6e246f, but for the libcxxabi
and libunwind test suites.
Differential Revision: https://reviews.llvm.org/D147628
With current versions of mingw-w64, TLS destructors that are registered
while executing TLS destructors are lost and leaked.
The root cause does get fixed further upstream in mingw-w64 in
71eddccd74
though, but mark the test as unsupported for now. The marking can be
removed later when the version used in the CI runner has been updated
to include the fix.
Differential Revision: https://reviews.llvm.org/D147859
This is the same as c218c80c73,
but for libcxxabi and libunwind.
This fixes running tests on Windows with Python installed in
e.g. "C:\Program Files\Python38".
Differential Revision: https://reviews.llvm.org/D147629
