Commit Graph

21 Commits

Author SHA1 Message Date
Louis Dionne e39095a32e [libc++] Define _LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER whenever we enable warnings in the test suite
This should make CI consistent on all the compilers we support. Most of
this patch is working around various warnings emitted by GCC in our code
base, which are now being shown when we compile the tests.

After this patch, the whole test suite should be warning free on all
compilers we support and test, except for a few warnings on GCC that
we silence explicitly until we figure out the proper fix for them.

Differential Revision: https://reviews.llvm.org/D120684
2022-03-15 17:17:54 -04:00
Joe Loser d2baefae68
[libc++] Replace _LIBCPP_HAS_NO_CONCEPTS with _LIBCPP_STD_VER > 17. NFCI.
All supported compilers that support C++20 now support concepts. So, remove
`_LIB_LIBCPP_HAS_NO_CONCEPTS` in favor of `_LIBCPP_STD_VER > 17`. Similarly in
the tests, remove `// UNSUPPORTED: libcpp-no-concepts`.

Differential Revision: https://reviews.llvm.org/D121528
2022-03-13 12:32:06 -04:00
Arthur O'Dwyer 7624552ead [libc++] Explicitly reject URNG types with signed result_types.
Fixes #48965.

Differential Revision: https://reviews.llvm.org/D120630
2022-03-02 10:28:48 -05:00
Louis Dionne 368faacac7 [libc++] Revert "Protect users from relying on detail headers" & related changes
This commit reverts 5aaefa51 (and also partly 7f285f48e7 and b6d75682f9,
which were related to the original commit). As landed, 5aaefa51 had
unintended consequences on some downstream bots and didn't have proper
coverage upstream due to a few subtle things. Implementing this is
something we should do in libc++, however we'll first need to address
a few issues listed in https://reviews.llvm.org/D106124#3349710.

Differential Revision: https://reviews.llvm.org/D120683
2022-03-01 08:20:24 -05:00
Arthur O'Dwyer a3255f219a [libc++] Explicitly reject `uniform_int_distribution<bool>` and `<char>`.
`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
2022-02-28 14:57:53 -05:00
Christopher Di Bella 5aaefa510e [libcxx][modules] protects users from relying on detail headers
libc++ has started splicing standard library headers into much more
fine-grained content for maintainability. It's very likely that outdated
and naive tooling (some of which is outside of LLVM's scope) will
suggest users include things such as <__ranges/access.h> instead of
<ranges>, and Hyrum's law suggests that users will eventually begin to
rely on this without the help of tooling. As such, this commit
intends to protect users from themselves, by making it a hard error for
anyone outside of the standard library to include libc++ detail headers.

Differential Revision: https://reviews.llvm.org/D106124
2022-02-26 09:00:25 +00:00
Nikolas Klauser a7c2a6289c [libc++] Guard warning pragmas
This makes the GCC output even cleaner!

Reviewed By: ldionne, #libc

Spies: mstorsjo, Quuxplusone, Mordante, libcxx-commits

Differential Revision: https://reviews.llvm.org/D119295
2022-02-15 00:41:11 +01:00
Arthur O'Dwyer fa6b9e4010 [libc++] Normalize all our '#pragma GCC system_header', and regression-test.
Now we'll notice if a header forgets to include this magic phrase.

Differential Revision: https://reviews.llvm.org/D118800
2022-02-04 12:27:19 -05:00
Arthur O'Dwyer 38db42d004 [libc++] [NFC] s/_LIBCPP_STD_VER > 17 && !defined(_LIBCPP_HAS_NO_CONCEPTS)/!defined(_LIBCPP_HAS_NO_CONCEPTS)/
Per Discord discussion, we're normalizing on a simple `!defined(_LIBCPP_HAS_NO_CONCEPTS)`
so that we can do a big search-and-replace for `!defined(_LIBCPP_HAS_NO_CONCEPTS)`
back into `_LIBCPP_STD_VER > 17` when we're ready to abandon support for concept-syntax-less
compilers.

Differential Revision: https://reviews.llvm.org/D118748
2022-02-02 11:02:56 -05:00
Arthur O'Dwyer 8b29b84c99 [libc++] Fix LWG3422 "Issues of seed_seq's constructors"
https://cplusplus.github.io/LWG/issue3422

Also add a static_assert to check the "Mandates:" on the
iterator-pair constructor. Oddly, the `InputIterator` parameter
itself is merely preconditioned, not constrained, to satisfy the
input iterator requirements.

Also drive-by rename `init` to `__init`.

Differential Revision: https://reviews.llvm.org/D117962
2022-01-24 20:14:25 -05:00
Arthur O'Dwyer 0359b85c61 [libc++] [ABI BREAK] Conform lognormal_distribution::param_type.
Fixes #52906.

Differential Revision: https://reviews.llvm.org/D116344
2022-01-17 10:22:41 -05:00
Louis Dionne d202c76441 [libc++] Start using `arc4random()` to implement `std::random_device` on Apple
On Apple platforms, arc4random is faster than /dev/urandom, and it is
the recommended user-space RNG according to Apple's own OS folks.

This commit adds an ABI switch to guard ABI-break-protections in
std::random_device, and starts using arc4random instead of /dev/urandom
to implement std::random_device on Apple platforms.

Note that previously, `std::random_device` would allow passing a custom
token to its constructor, and that token would be interpreted as the name
of a file to read entropy from. This was implementation-defined and
undocumented. After this change, Apple platforms will be using arc4random()
instead, and any custom token passed to the constructor will be ignored.
This behavioral change will also impact other platforms that use the
arc4random() implementation, such as OpenBSD. This should be fine since
that is effectively a relaxation of the constructor's requirements.

rdar://86638350

Differential Revision: https://reviews.llvm.org/D116045
2022-01-12 11:24:23 -05:00
Arthur O'Dwyer 4d81a46f7f [libc++] Alphabetize header #includes. NFCI.
The NFC part of D116809. We still want to enforce this in CI,
but the mechanism for that is still to-be-determined.

Differential Revision: https://reviews.llvm.org/D116809
2022-01-10 16:30:38 -05:00
Louis Dionne beff71520b [libc++] Partially revert 346ef5e587
This moves the macro definitions back to __config, but keeps the
improved documentation. 346ef5e587 had broken the MinGW build.
2021-12-21 23:58:17 +02:00
Louis Dionne 346ef5e587 [libc++][NFC] Improve documentation of the various random_device implementations
Also, move the setting of the macro closer to its point of use, which
also has the benefit of uncluttering `__config`.
2021-12-21 15:32:09 -05:00
Louis Dionne e03ce65190 [libc++][NFC] Reformatting in random_device.h and random.cpp 2021-12-21 13:32:56 -05:00
Nikolas Klauser feb80aa96b [libc++] `= delete` member functions with // = delete;
Use `= delete` for member functions that are marked with `// = delete;`

Reviewed By: ldionne, Quuxplusone, #libc

Spies: jloser, libcxx-commits

Differential Revision: https://reviews.llvm.org/D115291
2021-12-08 19:29:44 +01:00
Louis Dionne 81eda008e9 [libc++] Extract __clamp_to_integral to its own header
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
2021-12-08 08:33:37 -05:00
Fabian Wolff b254c2e2c4 [libc++] Fix `uniform_int_distribution` for 128-bit result type
Fixes https://llvm.org/PR51520. The problem is that `uniform_int_distribution`
currently uses an unsigned integer with at most 64 bits internally, which
is then casted to the desired result type. If the result type is `int64_t`,
this will produce a negative number if the most significant bit is set,
but if the result type is `__int128_t`, the value remains non-negative
and will be out of bounds for the example in PR#51520. (The reason why
it also seems to work if the upper or lower bound is changed is
because the branch at [1] will then no longer be taken, and proper
rejection sampling takes place.)

The bigger issue here is probably that `uniform_int_distribution` can be
instantiated with `__int128_t` but will silently produce incorrect results
(only the lowest 64 bits can ever be set). libstdc++ also supports `__int128_t`
as a result type, so I have simply extended the maximum width of the
internal intermediate result type.

[1]: https://github.com/llvm/llvm-project/blob/6d28dffb6/libcxx/include/__random/uniform_int_distribution.h#L266-L267

Differential Revision: https://reviews.llvm.org/D114129
2021-12-01 11:03:29 -05:00
Arthur O'Dwyer 344cef6695 [libc++] Granularize the <random> header. NFCI.
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
2021-11-22 13:24:27 -05:00
Louis Dionne 134723edd5 [libcxx] Move all algorithms into their own headers
This is a fairly mechanical change, it just moves each algorithm into
its own header. This is intended to be a NFC.

This commit re-applies 7ed7d4ccb8, which was reverted in 692d7166f7
because the Modules build got broken. The modules build has now been
fixed, so we're re-committing this.

Differential Revision: https://reviews.llvm.org/D103583

Attribution note
----------------
I'm only committing this. This commit is a mix of D103583, D103330 and
D104171 authored by:

Co-authored-by: Christopher Di Bella <cjdb@google.com>
Co-authored-by: zoecarver <z.zoelec2@gmail.com>
2021-06-19 07:49:06 -04:00