Instead of using a temporary `string` in `__vformat_to_wrapped` use a new
generic iterator. This aids to reduce the number of template instantions
and avoids using a `string` to buffer the entire formatted output.
This changes the type of `format_context` and `wformat_context`, this can
still be done since the code isn't ABI stable yet.
Several approaches have been evaluated:
- Using a __output_buffer base class with:
- a put function to store the buffer in its internal buffer
- a virtual flush function to copy the internal buffer to the output
- Using a `function` to forward the output operation to the output buffer,
much like the next method.
- Using a type erased function point to store the data in the buffer.
The last version resulted in the best performance. For some cases there's
still a loss of speed over the original method. This loss many becomes
apparent when large strings are copied to a pointer like iterator, before
the compiler optimized this using `memcpy`.
Reviewed By: ldionne, vitaut, #libc
Differential Revision: https://reviews.llvm.org/D110495
`uniform_int_distribution<T>` is UB unless `T` is one of the non-character,
non-boolean integer types (`short` or larger). However, libc++ has never
enforced this. D114129 accidentally made `uniform_int_distribution<bool>`
into an error. Make it now *intentionally* an error; and likewise for the
character types and all user-defined class and enum types; but permit
`__[u]int128_t` to continue working.
Apply the same static_assert to all the integer distributions.
Differential Revision: https://reviews.llvm.org/D114920
This is the first step towards disentangling the debug mode and assertions
in libc++. This patch doesn't make any functional change: it simply moves
_LIBCPP_ASSERT-related stuff to its own file so as to make it clear that
libc++ assertions and the debug mode are different things. Future patches
will make it possible to enable assertions without enabling the debug
mode.
Differential Revision: https://reviews.llvm.org/D119769
`<filesystem>` header has been around for a while now, so we can safely remove
`<experimental/filesystem>` header. `_LIBCPP_DEPRECATED_EXPERIMENTAL_FILESYSTEM`
suggests we were going to remove `<experimental/filesystem>` in llvm 11 release,
but we never did. So, remove the experimental header now, its associated tests,
and the `_LIBCPP_DEPRECATED_EXPERIMENTAL_FILESYSTEM` macro.
Differential Revision: https://reviews.llvm.org/D119603
Back in https://reviews.llvm.org/D109459, we stopped using the C++03
emulation for std::nullptr_t by default, which was an ABI break. We
still left a knob for users to turn it back on if they were broken by
the change, with a note that we would remove that knob after one release.
The time has now come to remove the knob and clean up the std::nullptr_t
emulation.
Differential Revision: https://reviews.llvm.org/D114786
For some reason `<string>` defines `std::fpos`, which should be defined in `<ios>`.
Reviewed By: Quuxplusone, Mordante, #libc
Spies: libcxx-commits, mgorny
Differential Revision: https://reviews.llvm.org/D118914
Discovered in the comments on D118748: we would like this namespace
to exist anytime Ranges exists, regardless of whether concepts syntax
is supported. Also, we'd like to fully granularize the <ranges> header,
which means not putting any loose declarations at the top level.
Differential Revision: https://reviews.llvm.org/D118809
The tests for these are just copy-pasted from the tests for std::{strong,weak,partial}_order,
and then I added an extra clause in each (test_2()) to test the stuff that's not just the same
as std::*_order.
This also includes the fix for https://wg21.link/LWG3465 (which falls naturally out of the
"you must write it three times" style, but I've added test cases for it also).
There is an action item here to go back and give good diagnostics for SFINAE failures
in these CPOs. I've filed this as https://github.com/llvm/llvm-project/issues/53456 .
Differential Revision: https://reviews.llvm.org/D111514
This implements the last required formatter specialization.
Completes:
- LWG 3251 Are std::format alignment specifiers applied to string arguments?
- LWG 3340 Formatting functions should throw on argument/format string mismatch in §[format.functions]
- LWG 3540 §[format.arg] There should be no const in basic_format_arg(const T* p)
Implements parts of:
- P0645 Text Formatting
Depends on D114001
Reviewed By: ldionne, vitaut, #libc
Differential Revision: https://reviews.llvm.org/D115988
This properly implements the formatter for floating-point types.
Completes:
- P1652R1 Printf corner cases in std::format
- LWG 3250 std::format: # (alternate form) for NaN and inf
- LWG 3243 std::format and negative zeroes
Implements parts of:
- P0645 Text Formatting
Reviewed By: #libc, ldionne, vitaut
Differential Revision: https://reviews.llvm.org/D114001
As prefigured in the comments on D115315.
This gives us one unified style for all niebloids,
and also simplifies the modulemap.
Differential Revision: https://reviews.llvm.org/D116570
This change is the basis for a further refactoring where I'm going to
split up the various implementations we have in __threading_support to
make that code easier to understand.
Note that I had to make __convert_to_timespec a template to break
circular dependencies. Concretely, we never seem to use it with anything
other than ::timespec, but I am wary of hardcoding that assumption as
part of this change, since I suspect there's a reason for going through
these hoops in the first place.
Differential Revision: https://reviews.llvm.org/D116944
I didn't split the calendar bits more than this because there was little
benefit to doing it, and I know our calendar support is incomplete.
Whoever picks up the missing calendar bits can organize these headers
at their leisure.
Differential Revision: https://reviews.llvm.org/D116965
Clang is gaining `auto(x)` support in D113393; sadly there
seems to be no feature-test macro for it. Zhihao is opening
a core issue for that macro.
Use `_LIBCPP_AUTO_CAST` where C++20 specifies we should use `auto(x)`;
stop using `__decay_copy(x)` in those places.
In fact, remove `__decay_copy` entirely. As of C++20, it's purely
a paper specification tool signifying "Return just `x`, but it was
perfect-forwarded, so we understand you're going to have to call
its move-constructor sometimes." I believe there's no reason we'd
ever need to do its operation explicitly in code.
This heisenbugs away a test failure on MinGW; see D112214.
Differential Revision: https://reviews.llvm.org/D115686
__transaction is a helper class that allows rolling back code in case an
exception is thrown. The main goal is to reduce the clutter when code
needs to be guarded with `#if _LIBCPP_NO_EXCEPTIONS`.
Differential Revision: https://reviews.llvm.org/D115730
Also:
- refactor out `__voidify`;
- use the `destroy` algorithm internally;
- refactor out helper classes used in tests for `uninitialized_*`
algorithms.
Differential Revision: https://reviews.llvm.org/D115626
Defined in [`specialized.algorithms`](wg21.link/specialized.algorithms).
Also:
- refactor the existing non-range implementation so that most of it
can be shared between the range-based and non-range-based algorithms;
- remove an existing test for the non-range version of
`uninitialized_default_construct{,_n}` that likely triggered undefined
behavior (it read the values of built-ins after default-initializing
them, essentially reading uninitialized memory).
Reviewed By: #libc, Quuxplusone, ldionne
Differential Revision: https://reviews.llvm.org/D115315
Just defensive CMake-ing. I pulled this from D115544 and D99484 which
are blocked on some lldb CI failures I don't yet understand. Hoping to land
something smaller in the meantime.
Reviewed By: #libc, ldionne
Differential Revision: https://reviews.llvm.org/D115566
In addition to being more consistent with our approach for helpers, this
solves an actual issue where <cmath> was using numeric_limits but never
including the <limits> header directly. In a normal setup, this is not
an issue because the <math.h> header included by <cmath> does include
<limits>. However, I did stumble upon some code where that didn't work,
most likely because they were placing their own <math.h> header in front
of ours. I didn't bother investigating further.
Differential Revision: https://reviews.llvm.org/D115282
Implement the exposition-only concepts specified in
`[special.mem.concepts]`. These are all thin wrappers over other
concepts.
Reviewed By: #libc, Quuxplusone, ldionne
Differential Revision: https://reviews.llvm.org/D114761
This does not include `std::compare_*_fallback`; those are coming later.
There's still an open question of how to implement std::strong_order
for `long double`, which has 80 value bits and 48 padding bits on x86-64,
and which is presumably *not* IEEE 754-compliant on PPC64 and so on.
So that part is left unimplemented.
Differential Revision: https://reviews.llvm.org/D110738
Actually there's one functional change here, which is that users can
no longer depend on <random> to include all of C++20 <concepts>. That
inclusion is so new that we believe nobody should be depending on it
yet, even in the presence of Hyrum's Law. We keep the includes of <vector>,
<algorithm>, etc., so as not to break pre-C++20 Hyrum's Law users.
Differential Revision: https://reviews.llvm.org/D114281