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@ChrisDenton ChrisDenton commented Dec 14, 2025

Successful merges:

r? @ghost
@rustbot modify labels: rollup

Create a similar rollup

jamie-osec and others added 30 commits December 10, 2025 21:45
This commit introduces two new constants to SystemTime: `MIN` and `MAX`,
whose value represent the maximum values for the respective data type,
depending upon the platform.

Technically, this value is already obtainable during runtime with the
following algorithm: Use `SystemTime::UNIX_EPOCH` and call `checked_add`
(or `checked_sub`) repeatedly with `Duration::new(0, 1)` on it, until it
returns None.  Mathematically speaking, this algorithm will terminate
after a finite amount of steps, yet it is impractical to run it, as it
takes practically forever.

Besides, this commit also adds a unit test.  Concrete implementation
depending upon the platform is done in later commits.

In the future, the hope of the authors lies within the creation of a
`SystemTime::saturating_add` and `SystemTime::saturating_sub`, similar
to the functions already present in `std::time::Duration`.  However, for
those, these constants are crucially required, thereby this should be
seen as the initial step towards this direction.

Below are platform specifc notes:

# Hermit

The HermitOS implementation is more or less identitcal to the Unix one.

# sgx

The implementation uses a `Duration` to store the Unix time, thereby
implying `Duration::ZERO` and `Duration::MAX` as the limits.

# solid

The implementation uses a `time_t` to store the system time within a
single value (i.e. no dual secs/nanosecs handling), thereby implying its
`::MIN` and `::MAX` values as the respective boundaries.

# UEFI

UEFI has a weird way to store times, i.e. a very complicated struct.
The standard proclaims "1900-01-01T00:00:00+0000" to be the lowest
possible value and `MAX_UEFI_TIME` is already present for the upper
limit.

# Windows

Windows is weird.  The Win32 documentation makes no statement on a
maximum value here.  Next to this, there are two conflicting types:
`SYSTEMTIME` and `FILETIME`.  Rust's Standard Library uses `FILETIME`,
whose limit will (probably) be `i64::MAX` packed into two integers.
However, `SYSTEMTIME` has a lower-limit.

# xous

It is similar to sgx in the sense of using a `Duration`.

# unsupported

Unsupported platforms store a `SystemTime` in a `Duration`, just like
sgx, thereby implying `Duration::ZERO` and `Duration::MAX` as the
respective limits.
This updates to mdbook 0.5.2 from mdbook 0.4.52. A primary aspect of
this change is that it splits the `mdbook` crate into multiple crates,
and various API changes and cleanup.

There's full release notes and a migration guide at
https://github.com/rust-lang/mdBook/blob/master/CHANGELOG.md#mdbook-050.

This also includes submodule updates:

## book

2 commits in 8c0eacd5c4acbb650497454f3a58c9e8083202a4..39aeceaa3aeab845bc4517e7a44e48727d3b9dbe
2025-11-18 10:36:41 -0500 to 2025-12-12 11:02:27 -0500
- Synchronize TrplNote name
- Update to mdbook 0.5

## edition-guide

1 commits in 9cf5443d632673c4d41edad5e8ed8be86eeb3b8f..c3c0f0b3da26610138b7ba7663f60cd2c68cf184
2025-11-15 21:51:11 +0000 to 2025-11-28 18:54:18 +0000
- Update to mdbook 0.5 (rust-lang/edition-guide#381)

## nomicon

2 commits in 0fe83ab28985b99aba36a1f0dbde3e08286fefda..9fe8fa599ad228dda74f240cc32b54bc5c1aa3e6
2025-11-15 00:03:14 +0000 to 2025-12-03 11:54:04 +0000
- Remove references to outdated unsafe code guidelines (rust-lang/nomicon#512)
- Update to mdbook 0.5 (rust-lang/nomicon#511)

## reference

5 commits in b14b4e40f53ca468beaf2f5d0dfb4f4c4ba6bc7b..50c5de90487b68d429a30cc9466dc8f5b410128f
2025-12-02 21:17:44 +0000 to 2025-12-09 22:19:05 +0000
- UB: update the extra clause for provenance UB during const evaluation (rust-lang/reference#2091)
- Remove `[no-mentions]` handler in our triagebot config (rust-lang/reference#2102)
- Clarify that omitting `nostack` is a promise from the compiler to the programmer (rust-lang/reference#1999)
- Specify that range patterns must be nonempty. (rust-lang/reference#2093)
- Update to mdbook 0.5 (rust-lang/reference#2096)

## rust-by-example

1 commits in 111cfae2f9c3a43f7b0ff8fa68c51cc8f930637c..7d21279e40e8f0e91c2a22c5148dd2d745aef8b6
2025-11-27 17:16:42 -0300 to 2025-12-01 15:02:09 -0300
- Update to mdbook 0.5 (rust-lang/rust-by-example#1977)
This solves the "can't find the upvar" ICEs that resulted from
`maybe_read_scrutinee` being unfit for purpose.
The split between walk_pat and maybe_read_scrutinee has now become
redundant.

Due to this change, one testcase within the testsuite has become similar
enough to a known ICE to also break. I am leaving this as future work,
as it requires feature(type_alias_impl_trait)
As per code review, it is preferred to not use derives in tests that
aren't about them.
This aims to make each major part responsible for modifying the
precision be visible in the logs.
As Nadrieril remarked, the previous comment was misleadingly framed.
See clippy issue 16086 for context
Expect the entire input to be a single XML document, instead of
reading it line by line. This detects trailing junk better.
Copied validate_junit.py from libtest-junit.

JUnit format works well in edition 2021, but is currently broken
in edition 2024 by the mergeable doctest report.
Fix the panic in write_message() which expects messages to contain
no embedded newlines. We still want a trailing newline at the end
of the file though, so write it in different manner.

Doctest runner no longer panics, but the output is kinda broken
when `compile_fail` doctests are present. This is because they
are not mergeable.
There is a slight edge case when adding and subtracting a `Duration`
from a `SystemTime`, namely when the duration itself is finer/smaller
than the time precision on the operating systems.

On most (if not all non-Windows) operating systems, the precision of
`Duration` aligns with the `SystemTime`, both being one nanosecond.

However, on Windows, this time precision is 100ns, meaning that adding
or subtracting a `Duration` whose value is `< Duration::new(0, 100)`
will result in that method behaving like an addition/subtracting of
`Duration::ZERO`, due to the `Duration` getting rounded-down to the zero
value.
The Windows implementation of `SystemTime::checked_sub` contains a bug,
namely that it does not return `None` on values below 1601.

This bug stems from the fact that internally, the time gets converted to
an i64, with zero representing the anchor in 1601.  Of course,
performing checked subtraction on a signed integer generally works fine.
However, the resulting value delivers undefined behavior on Windows
systems.

To mitigate this issue, we try to convert the resulting i64 to an u64
because a negative value should obviously fail there.
…=ChrisDenton

Add SystemTime::{MIN, MAX}

Accepted ACP: <rust-lang/libs-team#692>
Tracking Issue: <rust-lang#149067>

---

This merge request introduces two new constants to `SystemTime`: `MIN` and `MAX`, whose values represent the maximum values for the respective data type, depending upon the platform.

Technically, this value is already obtainable during runtime with the following algorithm:
Use `SystemTime::UNIX_EPOCH` and call `checked_add` (or `checked_sub`) repeatedly with `Duration::new(0, 1)` on it, until it returns None.
Mathematically speaking, this algorithm will terminate after a finite amount of steps, yet it is impractical to run it, as it takes practically forever.

Besides, this commit also adds a unit test to verify those values represent the respective minimum and maximum, by letting a `checked_add` and `checked_sub` on it fail.

In the future, the hope of the authors lies within the creation of a `SystemTime::saturating_add` and `SystemTime::saturating_sub`, similar to the functions already present in `std::time::Duration`.
However, for those, these constants are crucially required, thereby this should be seen as the initial step towards this direction.
With this change, implementing these functions oneself outside the standard library becomes feasible in a portable manner for the first time.

This feature (and a related saturating version of `checked_{add, sub}` has been requested multiple times over the course of the past few years, most notably:
* rust-lang#100141
* rust-lang#133525
* rust-lang#105762
* rust-lang#71224
* rust-lang#45448
* rust-lang#52555
…Mark-Simulacrum

tidy: Detect outdated workspaces in workspace list

Detects the case in rust-lang#149415 (will pass CI once that lands).
Fix trailing newline in JUnit formatter

`write_message()` expects messages to contain no newlines.

Fixes rust-lang#149436
Update to mdbook 0.5

This updates to mdbook 0.5.2 from mdbook 0.4.52. A primary aspect of this change is that it splits the `mdbook` crate into multiple crates, and various API changes and cleanup.

There's full release notes and a migration guide at https://github.com/rust-lang/mdBook/blob/master/CHANGELOG.md#mdbook-050.

This also includes submodule updates:

## book

1 commits in 8c0eacd5c4acbb650497454f3a58c9e8083202a4..9c9104e8a82430f97f42e738051bda718919211c
2025-11-18 10:36:41 -0500 to 2025-12-10 11:33:49 -0500
- Update to mdbook 0.5

## edition-guide

1 commits in 9cf5443d632673c4d41edad5e8ed8be86eeb3b8f..c3c0f0b3da26610138b7ba7663f60cd2c68cf184
2025-11-15 21:51:11 +0000 to 2025-11-28 18:54:18 +0000
- Update to mdbook 0.5 (rust-lang/edition-guide#381)

## nomicon

2 commits in 0fe83ab28985b99aba36a1f0dbde3e08286fefda..9fe8fa599ad228dda74f240cc32b54bc5c1aa3e6
2025-11-15 00:03:14 +0000 to 2025-12-03 11:54:04 +0000
- Remove references to outdated unsafe code guidelines (rust-lang/nomicon#512)
- Update to mdbook 0.5 (rust-lang/nomicon#511)

## reference

5 commits in b14b4e40f53ca468beaf2f5d0dfb4f4c4ba6bc7b..50c5de90487b68d429a30cc9466dc8f5b410128f
2025-12-02 21:17:44 +0000 to 2025-12-09 22:19:05 +0000
- UB: update the extra clause for provenance UB during const evaluation (rust-lang/reference#2091)
- Remove `[no-mentions]` handler in our triagebot config (rust-lang/reference#2102)
- Clarify that omitting `nostack` is a promise from the compiler to the programmer (rust-lang/reference#1999)
- Specify that range patterns must be nonempty. (rust-lang/reference#2093)
- Update to mdbook 0.5 (rust-lang/reference#2096)

## rust-by-example

1 commits in 111cfae2f9c3a43f7b0ff8fa68c51cc8f930637c..7d21279e40e8f0e91c2a22c5148dd2d745aef8b6
2025-11-27 17:16:42 -0300 to 2025-12-01 15:02:09 -0300
- Update to mdbook 0.5 (rust-lang/rust-by-example#1977)
…donszelmann

Cleanup of attribute parsing errors

Removes the specific `UnknownMetaItem` and `IllFormedAttributeInputLint` errors.
Note that `IllFormedAttributeInputLint` is not a lint, contrary to its name

r? ```@jdonszelmann```
Fix typo in armv7a-vex-v5 documentation

Fixed a typo in the platform support documentation for the `armv7a-vex-v5` target.
@rustbot rustbot added A-attributes Area: Attributes (`#[…]`, `#![…]`) A-run-make Area: port run-make Makefiles to rmake.rs A-tidy Area: The tidy tool O-hermit Operating System: Hermit O-SGX Target: SGX O-solid Operating System: SOLID O-unix Operating system: Unix-like O-windows Operating system: Windows S-waiting-on-review Status: Awaiting review from the assignee but also interested parties. T-bootstrap Relevant to the bootstrap subteam: Rust's build system (x.py and src/bootstrap) T-clippy Relevant to the Clippy team. T-compiler Relevant to the compiler team, which will review and decide on the PR/issue. T-libs Relevant to the library team, which will review and decide on the PR/issue. T-rustdoc Relevant to the rustdoc team, which will review and decide on the PR/issue. T-style Relevant to the style team, which will review and decide on the PR/issue. labels Dec 14, 2025
@ChrisDenton
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@bors r+ rollup=never p=5

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bors commented Dec 14, 2025

📌 Commit fb97a27 has been approved by ChrisDenton

It is now in the queue for this repository.

@bors bors added S-waiting-on-bors Status: Waiting on bors to run and complete tests. Bors will change the label on completion. and removed S-waiting-on-review Status: Awaiting review from the assignee but also interested parties. labels Dec 14, 2025
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The job aarch64-gnu-llvm-20-2 failed! Check out the build log: (web) (plain enhanced) (plain)

Click to see the possible cause of the failure (guessed by this bot)
stack backtrace:
   0: __rustc::rust_begin_unwind
   1: core::panicking::panic_fmt
   2: core::panicking::assert_failed_inner
   3: core::panicking::assert_failed::<u64, u64>
   4: hir_ty::layout::tests::check_size_and_align_expr
   5: hir_ty::layout::tests::closure::match_pattern
   6: <hir_ty::layout::tests::closure::match_pattern::{closure#0} as core::ops::function::FnOnce<()>>::call_once
note: Some details are omitted, run with `RUST_BACKTRACE=full` for a verbose backtrace.
---- layout::tests::closure::match_pattern stdout end ----
---- layout::tests::closure::capture_specific_fields stdout ----

thread 'layout::tests::closure::capture_specific_fields' (75988) panicked at src/tools/rust-analyzer/crates/hir-ty/src/layout/tests/closure.rs:169:5:
assertion `left == right` failed: size mismatch
  left: 48
 right: 16
stack backtrace:
   0: __rustc::rust_begin_unwind
   1: core::panicking::panic_fmt
   2: core::panicking::assert_failed_inner
   3: core::panicking::assert_failed::<u64, u64>
   4: hir_ty::layout::tests::check_size_and_align_expr
   5: hir_ty::layout::tests::closure::capture_specific_fields
   6: <hir_ty::layout::tests::closure::capture_specific_fields::{closure#0} as core::ops::function::FnOnce<()>>::call_once
note: Some details are omitted, run with `RUST_BACKTRACE=full` for a verbose backtrace.
---- layout::tests::closure::capture_specific_fields stdout end ----

failures:
    layout::tests::closure::match_pattern
    layout::tests::closure::capture_specific_fields

test result: FAILED. 924 passed; 2 failed; 1 ignored; 0 measured; 0 filtered out; finished in 1.56s

error: test failed, to rerun pass `-p hir-ty --lib`
Bootstrap failed while executing `--stage 2 test --skip tests --skip coverage-map --skip coverage-run --skip library --skip tidyselftest`
Build completed unsuccessfully in 0:47:11
  local time: Sun Dec 14 06:01:45 UTC 2025
  network time: Sun, 14 Dec 2025 06:01:46 GMT
##[error]Process completed with exit code 1.

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@bors r-

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A-attributes Area: Attributes (`#[…]`, `#![…]`) A-run-make Area: port run-make Makefiles to rmake.rs A-tidy Area: The tidy tool O-hermit Operating System: Hermit O-SGX Target: SGX O-solid Operating System: SOLID O-unix Operating system: Unix-like O-windows Operating system: Windows S-waiting-on-bors Status: Waiting on bors to run and complete tests. Bors will change the label on completion. T-bootstrap Relevant to the bootstrap subteam: Rust's build system (x.py and src/bootstrap) T-clippy Relevant to the Clippy team. T-compiler Relevant to the compiler team, which will review and decide on the PR/issue. T-libs Relevant to the library team, which will review and decide on the PR/issue. T-rustdoc Relevant to the rustdoc team, which will review and decide on the PR/issue. T-style Relevant to the style team, which will review and decide on the PR/issue.

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