This is the first round of TODOs created based on relnote todo output. There are many entries that need to be documented, expanded, reworded, and this change makes progress on setting that up. For this cycle, relnote todo implemented a simple heuristic of finding CLs that mention accepted proposals (see issue 62376, or comment https://go.dev/issue/62376#issuecomment-2101086794 specifically). The "Items that don't need to be mentioned in Go 1.23 release notes but are picked up by relnote todo." section in todo.md contains an attempt at reviewing that list. The large number of items needed to be reviewed made it impractical to spend much time on any individual one. For #65614. Change-Id: Id9d5f1795575a46df2ec4ed0088de07ee6075a90 Reviewed-on: https://go-review.googlesource.com/c/go/+/588015 Reviewed-by: Dmitri Shuralyov <dmitshur@google.com> Auto-Submit: Dmitri Shuralyov <dmitshur@golang.org> LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com> Reviewed-by: Carlos Amedee <carlos@golang.org>
1.5 KiB
Timer changes
Go 1.23 makes two significant changes to the implementation of [time.Timer] and [time.Ticker].
First, Timer
s and Ticker
s that are no longer referred to by the program
become eligible for garbage collection immediately, even if their
Stop
methods have not been called.
Earlier versions of Go did not collect unstopped Timer
s until after
they had fired and never collected unstopped Ticker
s.
Second, the timer channel associated with a Timer
or Ticker
is
now unbuffered, with capacity 0.
The main effect of this change is that Go now guarantees
that for any call to a Reset
or Stop
method, no stale values
prepared before that call will be sent or received after the call.
Earlier versions of Go used channels with a one-element buffer,
making it difficult to use Reset
and Stop
correctly.
A visible effect of this change is that len
and cap
of timer channels
now returns 0 instead of 1, which may affect programs that
poll the length to decide whether a receive on the timer channel
will succeed.
Such code should use a non-blocking receive instead.
These new behaviors are only enabled when the main Go program
is in a module with a go.mod
go
line using Go 1.23.0 or later.
When Go 1.23 builds older programs, the old behaviors remain in effect.
The new GODEBUG setting asynctimerchan=1
can be used to revert back to asynchronous channel behaviors
even when a program names Go 1.23.0 or later in its go.mod
file.