As mentioned in the LWG issue libc++ has already implemented the
optimization. This adds tests and documents the implementation defined
behaviour.
Drive-by fixes an initialization.
This PR is required to fix copy_file_large.pass.cpp which is failing on
z/OS in all ASCII variations. The problem is that a destination file is
opened in binary mode and auto-conversion does not happen when this lit
is compiled with -fzos-le-char-mode=ascii.
In addition opening a destination file will match a text mode of
`fopen()` of a source file.
So we can also match aarch64 triples which have four components instead of three when disabling the test, which the case on some buildbots.
Follow on to #89305
`libcxx std::basic_ios` uses `WEOF` to indicate the `fill` value is
uninitialized. On some platforms (e.g AIX and zOS in 64-bit mode)
`wchar_t` is 4 bytes `unsigned` and `wint_t` is also 4 bytes which means
`WEOF` cannot be distinguished from `WCHAR_MAX` by
`std::char_traits<wchar_t>::eq_int_type()`, meaning this valid character
value cannot be stored on affected platforms (as the implementation
triggers reinitialization to `widen(’ ’)`).
This patch introduces a new helper class `_FillHelper` uses a boolean
variable to indicate whether the fill character has been initialized,
which is used by default in libcxx ABI version 2. The patch does not
affect ABI version 1 except for targets AIX in 32- and 64-bit and z/OS
in 64-bit (so that the layout of the implementation is compatible with
the current IBM system provided libc++)
This is a continuation of Phabricator patch
[D124555](https://reviews.llvm.org/D124555). This patch uses a modified
version of the [approach](https://reviews.llvm.org/D124555#3566746)
suggested by @ldionne .
---------
Co-authored-by: Louis Dionne <ldionne.2@gmail.com>
Co-authored-by: David Tenty <daltenty.dev@gmail.com>
This patch removes many annotations that are not relevant anymore since
we don't support or test back-deploying to macOS < 10.13. It also cleans
up raw usage of target triples to identify versions of dylibs shipped on
prior versions of macOS, and uses the target-agnostic Lit features
instead. Finally, it reorders both the Lit backdeployment features and
the corresponding availability macros in the library in a way that makes
more sense, and reformulates the Lit backdeployment features in terms of
when a version of LLVM was introduced instead of encoding the system
versions on which it hasn't been introduced yet. Although one can be
derived from the other, encoding the negative form is extremely
error-prone.
Fixes#80901
We were not making any distinction between e.g. the "Apple-flavored"
libc++ built from trunk and the system-provided standard library on
Apple platforms. For example, any test that would be XFAILed on a
back-deployment target would unexpectedly pass when run on that
deployment target against the tip of trunk Apple-flavored libc++. In
reality, that test would be expected to pass because we're running
against the latest libc++, even if it is Apple-flavored.
To solve this issue, we introduce a new feature that describes whether
the Standard Library in use is the one provided by the system by
default, and that notion is different from the underlying standard
library flavor. We also refactor the existing Lit features to make a
distinction between availability markup and the library we're running
against at runtime, which otherwise limit the flexibility of what we can
express in the test suite. Finally, we refactor some of the
back-deployment versions that were incorrect (such as thinking that LLVM
10 was introduced in macOS 11, when in reality macOS 11 was synced with
LLVM 11).
Fixes#82107
3 error_code related cleanups/corrections in the std::filesystem
operations functions.
1. In `__copy`, the `ec->clear()` is unnecessary as `ErrorHandler` at
the start of each function clears the error_code as part of its
initialization.
2. In `__copy`, in the recursive codepath we are not checking the
error_code result of `it.increment(m_ec2)` immediately after use in the
for loop condition (and we aren't checking it after the final increment
when we don't enter the loop).
3. In `__weakly_canonical`, it makes calls to `__canonical` (which
internally uses OS APIs implementing POSIX `realpath`) and we are not
checking the error code result from the `__canonical` call. Both
`weakly_canonical` and `canonical` are supposed to set the error_code
when underlying OS APIs result in an error
(https://eel.is/c++draft/fs.err.report#3.1). With this change we
propagate up the error_code from `__canonical` caused by any underlying
OS API failure up to the `__weakly_canonical`. Essentially, if
`__canonical` thinks an error code should be set, then
`__weakly_canonical` must as well. Before this change it would be
throwing an exception in the non-error_code form of the function when
`__canonical` fails, while not setting the error code in the error_code
form of the function (an inconsistency).
Added a little coverage in weakly_canonical.pass.cpp for the error_code
forms of the API that was missing. Though I am lacking utilities in
libcxx testing to add granular testing of the failure scenarios (like
forcing realpath to fail for a given path, as it could if you had
something like a flaky remote filesystem).
* Guard `std::__make_from_tuple_impl` tests with `#ifdef _LIBCPP_VERSION` and `LIBCPP_STATIC_ASSERT`.
* Change `_LIBCPP_CONSTEXPR_SINCE_CXX20` to `TEST_CONSTEXPR_CXX20`.
+ Other functions in `variant.swap/swap.pass.cpp` were already using the proper test macro.
* Mark `what` as `[[maybe_unused]]` when used by `TEST_LIBCPP_REQUIRE`.
+ This updates one occurrence in `libcxx/test/libcxx` for consistency.
* Windows `_putenv_s()` takes 2 arguments, not 3.
+ See MSVC documentation: https://learn.microsoft.com/en-us/cpp/c-runtime-library/reference/putenv-s-wputenv-s?view=msvc-170
+ POSIX `setenv()` takes `int overwrite`, but Windows `_putenv_s()` always overwrites.
* Avoid non-Standard zero-length arrays.
+ Followup to #74183 and #79792.
* Add `operator++()` to `unsized_it`.
+ The Standard requires this due to [N4981][] [move.iter.requirements]/1 "The template parameter `Iterator` shall
either meet the *Cpp17InputIterator* requirements ([input.iterators])
or model `input_iterator` ([iterator.concept.input])."
+ MSVC's STL requires this because it has a strengthened exception
specification in `move_iterator` that inspects the underlying iterator's
increment operator.
* `uniform_int_distribution` forbids `int8_t`/`uint8_t`.
+ See [N4981][] [rand.req.genl]/1.5. MSVC's STL enforces this.
+ Note that when changing the distribution's `IntType`, we need to be
careful to preserve the original value range of `[0, max_input]`.
* fstreams are constructible from `const fs::path::value_type*` on wide systems.
+ See [ifstream.cons], [ofstream.cons], [fstream.cons].
* In `msvc_stdlib_force_include.h`, map `_HAS_CXX23` to `TEST_STD_VER` 23 instead of 99.
+ On 2023-05-23, 71400505ca
started recognizing 23 as a distinct value.
* Fix test name typo: `destory_elements.pass.cpp` => `destroy_elements.pass.cpp`
[N4981]: https://wg21.link/N4981
This patch implements LWG4023 by adding explicit assertions for the
added preconditions and also fixes a few tests that were violating these
preconditions.
On Windows you can not create symlinks without elevated privileges
unless you have Windows developer mode enabled. There's ~67 libcxx tests
that run into failures on windows if your environment is not set up
correctly (Go to windows settings and enable "developer mode").
This change:
- Adds a feature check for whether the host can create symlinks. (see
libcxx/utils/libcxx/test/features.py)
- Mark the feature as required for the 67 tests that hit failures on
windows due to this. This will allow lit to correctly mark these tests
as unsupported instead of unexpectedly failed (this is helpful since
then you know you didn't break something with your change, it's just
that it's not supported with your environment).
When calling setbuf(nullptr, 0) before performing file operations it
should set the file to unbuffered mode. Currently the code avoids
buffering internally, but the underlying stream still can buffer.
This is addressed by disabling the buffering of the underlying stream.
Fixes: https://github.com/llvm/llvm-project/issues/60509
When echo is used for piping, lit uses the system echo rather than the
builtin echo. The system echo on AIX doesn't support the `-n` option,
which causes these tests to fail. Use input redirection, so the builtin
echo can be used.
This fixes two issues.
The return value
----------------
Based on the wording
[istream.unformatted]/37
Effects: Behaves as an unformatted input function (as described above),
except that it does not count the number of characters extracted and
does not affect the value returned by subsequent calls to gcount().
After constructing a sentry object, if rdbuf() is a null pointer,
returns -1.
[istream.unformatted]/1
... It then creates an object of class sentry with the default argument
noskipws (second) argument true. If the sentry object returns true, when
converted to a value of type bool, the function endeavors to obtain the
requested input. ...
It could be argued the current behaviour is correct, however
constructing a istream rdbuf() == nullptr creates a sentry that returns
false; its state is always bad in this case.
As mentioned in the bug report, after this change the 3 major
implementations behave the same.
The setting of the state
------------------------
When pubsync returned -1 it updated the local __state variable and
returned. This early return caused the state up the istream not to be
updated to the new state.
Fixes: https://github.com/llvm/llvm-project/issues/51497
Fixes: https://github.com/llvm/llvm-project/issues/51499
---------
Co-authored-by: Louis Dionne <ldionne.2@gmail.com>
remove_all_impl() opens the target path with O_NOFOLLOW, which fails if
the target is a symbolic link. On FreeBSD, rather than returning ELOOP,
openat() returns EMLINK. This is unlikely to change for compatibility
reasons, see https://bugs.freebsd.org/bugzilla/show_bug.cgi?id=214633 .
Thus, check for EMLINK as well.
As suggested in #73262 this enable the stream printing on Apple
backdeployment targets. This omits the check whether the file is a
terminal. This is not entirely conforming, but the differences should be
minor and are typically not observable.
Fixes https://github.com/llvm/llvm-project/issues/75225
The overloads of `println` are specified in terms of `format`. The
function `format` is specified to work with ranges.
The implementations for `println` do not include `<format>`, but
libc++'s granularized header. This means the following example does not
work
#include <vector>
#include <print>
int main() {
std::vector<int> v{1, 2, 3};
std::println("{}", v);
}
(The other print functions also require this to work, they are specified
in terms of other format functions.)
Fixes: https://github.com/llvm/llvm-project/issues/71925
This patch adds a configuration of the libc++ test suite that enables
optimizations when building the tests. It also adds a new CI
configuration to exercise this on a regular basis. This is added in the
context of [1], which requires building with optimizations in order to
hit the bug.
[1]: https://github.com/llvm/llvm-project/issues/68552
Finishes implementation of
- P2093R14 Formatted output
- P2539R4 Should the output of std::print to a terminal be synchronized
with the underlying stream?
Differential Revision: https://reviews.llvm.org/D156609
This is the last PR that's needed (for now) to get libc++'s tests
working with MSVC's STL.
The ADDITIONAL_COMPILE_FLAGS machinery is very useful, but also very
problematic for MSVC, as it doesn't understand most of Clang's compiler
options. We've been dealing with this by simply marking anything that
uses ADDITIONAL_COMPILE_FLAGS as FAIL or SKIPPED, but that creates
significant gaps in test coverage.
Fortunately, ADDITIONAL_COMPILE_FLAGS also supports "features", which
can be slightly enhanced to send Clang-compatible and MSVC-compatible
options to the right compilers.
This patch adds the gcc-style-warnings and cl-style-warnings Lit features,
and uses that to pass the appropriate warning flags to tests. It also uses
TEST_MEOW_DIAGNOSTIC_IGNORED for a few local suppressions of MSVC
warnings.
Found while running libc++'s tests with MSVC's STL.
*
`libcxx/test/std/algorithms/alg.sorting/alg.heap.operations/sort.heap/ranges_sort_heap.pass.cpp`
+ Fix Clang `-Wunused-variable`, because `LIBCPP_ASSERT` expands to
nothing for MSVC's STL.
+ This is the same "always void-cast" change that #73437 applied to the
neighboring `complexity.pass.cpp`. I missed that
`ranges_sort_heap.pass.cpp` was also affected because we had disabled
this test.
*
`libcxx/test/std/input.output/file.streams/fstreams/ifstream.members/buffered_reads.pass.cpp`
*
`libcxx/test/std/input.output/file.streams/fstreams/ofstream.members/buffered_writes.pass.cpp`
+ Fix MSVC "warning C4244: '`=`': conversion from '`__int64`' to
'`_Ty`', possible loss of data".
+ This is a valid warning, possibly the best one that MSVC found in this
entire saga. We're accumulating a `std::vector<std::streamsize>` and
storing the result in `std::streamsize total_size` but we actually have
to start with `std::streamsize{0}` or we'll truncate.
*
`libcxx/test/std/input.output/filesystems/fs.enum/enum.path.format.pass.cpp`
+ Fix Clang `-Wunused-local-typedef` because the following usage is
libc++-only.
+ I'm just expanding it at the point of use, and using the dedicated
`LIBCPP_STATIC_ASSERT` to keep the line length down.
*
`libcxx/test/std/input.output/syncstream/syncbuf/syncstream.syncbuf.assign/swap.pass.cpp`
+ Fix MSVC "warning C4242: 'argument': conversion from '`int`' to
'`const _Elem`', possible loss of data".
+ This is a valid warning (possibly the second-best) as `sputc()`
returns `int_type`. If `sputc()` returns something unexpected, we want
to know, so we should separately say `expected.push_back(CharT('B'))`.
*
`libcxx/test/std/language.support/support.dynamic/new.delete/new.delete.single/new.size_align_nothrow.pass.cpp`
*
`libcxx/test/std/language.support/support.dynamic/new.delete/new.delete.single/new.size_nothrow.pass.cpp`
+ Fix MSVC "warning C6001: Using uninitialized memory '`x`'."
+ [N4964](https://wg21.link/N4964) \[new.delete.single\]/12:
> *Effects:* The deallocation functions
(\[basic.stc.dynamic.deallocation\]) called by a *delete-expression*
(\[expr.delete\]) to render the value of `ptr` invalid.
+ \[basic.stc.general\]/4:
> When the end of the duration of a region of storage is reached, the
values of all pointers representing the address of any part of that
region of storage become invalid pointer values (\[basic.compound\]).
Indirection through an invalid pointer value and passing an invalid
pointer value to a deallocation function have undefined behavior. Any
other use of an invalid pointer value has implementation-defined
behavior.
+ In certain configurations, after `delete x;` MSVC will consider `x` to
be radioactive (and in other configurations, it'll physically null out
`x` as a safety measure). We can copy it into `old_x` before deletion,
which the implementation finds acceptable.
*
`libcxx/test/std/ranges/range.adaptors/range.elements/general.pass.cpp`
*
`libcxx/test/std/ranges/range.adaptors/range.elements/iterator/deref.pass.cpp`
+ Fix MSVC "warning C4242: 'initializing': conversion from '`_Ty`' to
'`_Ty`', possible loss of data".
+ This was being emitted in `pair` and `tuple`'s perfect forwarding
constructors. Passing `short{1}` allows MSVC to see that no truncation
is happening.
*
`libcxx/test/std/ranges/range.adaptors/range.elements/iterator/member_types.compile.pass.cpp`
+ Fix MSVC "warning C4242: 'initializing': conversion from '`_Ty`' to
'`_Ty2`', possible loss of data".
+ Similarly, this was being emitted in `pair`'s perfect forwarding
constructor. After passing `short{1}`, I reduced repetition by relying
on CTAD. (I can undo that cleanup if it's stylistically undesirable.)
*
`libcxx/test/std/utilities/function.objects/refwrap/refwrap.const/type_conv_ctor.pass.cpp`
+ Fix MSVC "warning C4930: '`std::reference_wrapper<int> purr(void)`':
prototyped function not called (was a variable definition intended?)".
+ There's no reason for `purr()` to be locally declared (aside from
isolating it to a narrow scope, which has minimal benefits); it can be
declared like `meow()` above. 😸
*
`libcxx/test/std/utilities/memory/util.smartptr/util.smartptr.shared/util.smartptr.shared.create/make_shared_for_overwrite.pass.cpp`
*
`libcxx/test/std/utilities/smartptr/unique.ptr/unique.ptr.create/make_unique_for_overwrite.default_init.pass.cpp`
+ Fix MSVC static analysis warnings when replacing `operator new`:
```
warning C28196: The requirement that '(_Param_(1)>0)?(return!=0):(1)' is
not satisfied. (The expression does not evaluate to true.)
warning C6387: 'return' could be '0': this does not adhere to the
specification for the function 'new'.
warning C6011: Dereferencing NULL pointer 'reinterpret_cast<char
*>ptr+i'.
```
+ All we need is a null check, which appears in other `operator new`
replacements:
b85f1f9b18/libcxx/test/std/language.support/support.dynamic/new.delete/new.delete.single/new.size.replace.pass.cpp (L27-L28)
This is a syntax cleanup, not needed for running libc++'s tests with
MSVC's STL.
While changing
`libcxx/test/std/input.output/filesystems/fs.enum/enum.path.format.pass.cpp`
in #74965, I noticed that libc++'s tests almost always use the
special-purpose macros for "this is a libc++-specific `static_assert`
etc." defined by:
b85f1f9b18/libcxx/test/support/test_macros.h (L240-L253)
However, there were a very small number of occurrences that were using
the general-purpose `LIBCPP_ONLY` macro when they could have been using
the special-purpose macros. I believe that they should be cleaned up, to
make it easier to search for usage, and to make it clearer when the full
power of `LIBCPP_ONLY` is necessary.
This is a pure regex replacement from
`LIBCPP_ONLY\((assert|static_assert|ASSERT_NOEXCEPT|ASSERT_NOT_NOEXCEPT)\((.*)\)\);`
to `LIBCPP_\U$1($2);` using the power of [VSCode's case changing in
regex
replace](https://code.visualstudio.com/docs/editor/codebasics#_case-changing-in-regex-replace).
To avoid merge conflicts, this isn't changing the line in
`libcxx/test/std/input.output/filesystems/fs.enum/enum.path.format.pass.cpp`
that #74965 is already changing to use `LIBCPP_STATIC_ASSERT`.
Found while running libc++'s test suite with MSVC's STL.
* I've filed [LWG-4021](https://cplusplus.github.io/LWG/issue4021)
"`mdspan::is_always_meow()` should be `noexcept`" and implemented this
in libc++'s product and test code.
* Use `LIBCPP_STATIC_ASSERT` to avoid issues with `noexcept`
strengthening in MSVC's STL.
+ As permitted by the Standard, MSVC's STL conditionally strengthens
`mdspan` construction/`is_meow`/`stride` and `elements_view` iterator
`base() &&`, and always strengthens `basic_stringbuf` `swap`.
+ In `mdspan/properties.pass.cpp`, this also upgrades runtime `assert`s
to `static_assert`s.
* Improvement: Upgrade `assert` to `static_assert` when inspecting the
`noexcept`ness of `std::ranges::iter_move`. (These `!noexcept` tests
weren't causing issues for MSVC's STL, so I didn't change them to be
libc++-specific.)
This change requires quite a number of changes in the tests; this is not
code I expect people to use in the wild. So I don't expect breakage for
users.
Implements:
- P2905R2 Runtime format strings, as a Defect Report
Add proper explanation for cin.sh.cpp fail.
The stdin-is-piped.sh.cpp used to fail with old qemu (4.2.0), but should
pass now, as the qemu is updated now to 8.1.3 in CI.
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
<filesystem> is a C++17 addition. In C++11 and C++14 modes, we actually
have all the code for <filesystem> but it is hidden behind a non-inline
namespace __fs so it is not accessible. Instead of doing this unusual
dance, just guard the code for filesystem behind a classic C++17 check
like we normally do.
Found while running libc++'s test suite with MSVC's STL.
MSVC has a level 1 "warning C5101: use of preprocessor directive in
function-like macro argument list is undefined behavior". I don't know
why Clang doesn't complain about this.
There are some formatting tests which densely interleave preprocessor
directives within function-like macros, and they would need invasive
changes. For now, I'm just skipping those tests.
However, a few tests were only slightly affected, and I was able to add
a new test macro `TEST_IF_AIX` to make them portable.
I've structured this into a series of commits for even easier reviewing,
if that helps. I could easily split this up into separate PRs if
desired, but as this is low-risk with simple edits, I thought one PR
would be easiest.
* Drop unnecessary semicolons after function definitions.
* Cleanup comment typos.
* Cleanup `static_assert` typos.
* Cleanup test code typos.
+ There should be no functional changes, assuming I've changed all
occurrences.
* ~~Fix massive test code typos.~~
+ This was a real problem, but needed more surgery. I reverted those
changes here, and @philnik777 is fixing this properly with #73444.
* clang-formatting as requested by the CI.
This patch brings std::ios_base::noreplace from P2467R1 to libc++.
This requires compiling the shared library in C++23 mode since otherwise
fstream::open(...) doesn't know about the new flag.
Differential Revision: https://reviews.llvm.org/D137640
Co-authored-by: Louis Dionne <ldionne.2@gmail.com>
Instead of using individual macros to turn off missing C library
features, we use the using_if_exists attribute now. This patch removes
the _LIBCPP_HAS_NO_FGETPOS_FSETPOS macro used to workaround missing
fgetpos and fsetpos on older versions of Android -- using_if_exists
should take care of those in the headers and we should add appropriate
XFAILs to the tests instead of using TEST_HAS_NO_FGETPOS_FSETPOS.
This patch implements `std::basic_syncbuf` and `std::basic_osyncstream` as specified in paper p0053r7. ~~For ease of reviewing I am submitting this patch before submitting a patch for `std::basic_osyncstream`. ~~
~~Please note, this patch is not 100% complete. I plan on adding more tests (see comments), specifically I plan on adding tests for multithreading and synchronization.~~
Edit: I decided that it would be far easier for me to keep track of this and make changes that affect both `std::basic_syncbuf` and `std::basic_osyncstream` if both were in one patch.
The patch was originally written by @zoecarver
Implements
- P0053R7 - C++ Synchronized Buffered Ostream
- LWG-3127 basic_osyncstream::rdbuf needs a const_cast
- LWG-3334 basic_osyncstream move assignment and destruction calls basic_syncbuf::emit() twice
- LWG-3570 basic_osyncstream::emit should be an unformatted output function
- LWG-3867 Should std::basic_osyncstream's move assignment operator be noexcept?
Reviewed By: ldionne, #libc
Differential Revision: https://reviews.llvm.org/D67086
This patch fixes an ASAN-found issue in std::basic_filebuf where we'd
check the wrong size before proceeding to set our internal buffer to
the externally-provided buffer, leading to the library trying to read
from the incorrect buffer in underflow().
Thanks to Andrey Semin for the patch.
Differential Revision: https://reviews.llvm.org/D154514
