runtime: use timer.lock in runtimer

Continue using timer.lock to simplify timer operations.

[This is one CL in a refactoring stack making very small changes
in each step, so that any subtle bugs that we miss can be more
easily pinpointed to a small change.]

Change-Id: I504335a010d6eb4d7d627145b64a896582158406
Reviewed-on: https://go-review.googlesource.com/c/go/+/564129
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Reviewed-by: Ian Lance Taylor <iant@google.com>

runtime: use timer.lock in cleantimers

Continue using timer.lock to simplify timer operations.

[This is one CL in a refactoring stack making very small changes
in each step, so that any subtle bugs that we miss can be more
easily pinpointed to a small change.]

Change-Id: Ic12fd2630e8ac23cddd00fa7e3240a1ac19da596
Reviewed-on: https://go-review.googlesource.com/c/go/+/564126
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Reviewed-by: Ian Lance Taylor <iant@google.com>

runtime: use timer.lock in modtimer

Continue using timer.lock to simplify timer operations.

Note the removal of a previous potential deadlock.
(Explained at new line 325, there was a lock inversion
between individual timer locks and the 'timers' lock.)

[This is one CL in a refactoring stack making very small changes
in each step, so that any subtle bugs that we miss can be more
easily pinpointed to a small change.]

Change-Id: I8c9be00d13c6acd171a8aa2882a4fc844498f754
Reviewed-on: https://go-review.googlesource.com/c/go/+/564125
Reviewed-by: Ian Lance Taylor <iant@google.com>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>

runtime: add timer lock to lock ranking

No deadlocks yet!

Change-Id: I87fb3742a386d682fbcc8cb98e98771b54bc3fec
Reviewed-on: https://go-review.googlesource.com/c/go/+/564133
Reviewed-by: Austin Clements <austin@google.com>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>

runtime: use timer.lock in deltimer

The state set is now simplified enough that all the CAS loops
are starting to look the same: they are just spin locks.
So introduce an actual timer.lock method and use it in deltimer.

[This is one CL in a refactoring stack making very small changes
in each step, so that any subtle bugs that we miss can be more
easily pinpointed to a small change.]

Change-Id: Ifd7f20eeede5c764ef10ecba64855c29a5ddbe39
Reviewed-on: https://go-review.googlesource.com/c/go/+/564124
Reviewed-by: Ian Lance Taylor <iant@google.com>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>

runtime: merge timerDeleted into timerModified

When we make a change to a timer, we have to note the
desired change to t.when and then wait for the timer heap
owner to apply the change. There are two possible changes:
delete or set a new t.when. Most of the code for processing
these changes is the same, so we can simplify the code by
making both have the same state: timerDeleted is now
timerModified with t.nextwhen == 0.

This is part of a larger simplification of the state set.

[This is one CL in a refactoring stack making very small changes
in each step, so that any subtle bugs that we miss can be more
easily pinpointed to a small change.]

Change-Id: I1a2a12f8250bcd40f7b08b83f22c3a82b124eda6
Reviewed-on: https://go-review.googlesource.com/c/go/+/564123
Reviewed-by: Ian Lance Taylor <iant@google.com>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>

runtime: merge timerNoStatus into timerRemoved

For historical reasons, we have to treat a zero timer as
the same as an initialized timer that was stopped (removed).
The two states are already treated mostly identically.
Merge them.

This is part of a larger simplification of the state set.

[This is one CL in a refactoring stack making very small changes
in each step, so that any subtle bugs that we miss can be more
easily pinpointed to a small change.]

Change-Id: I9c3aeb8f92bafb18c47489c1ec20a7b87ac5cd9c
Reviewed-on: https://go-review.googlesource.com/c/go/+/564122
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Reviewed-by: Ian Lance Taylor <iant@google.com>

runtime: merge timerMoving into timerModifying

timerMoving is just a kind of "locked for modification",
so merge it into timerModifying.

This is part of a larger simplification of the state set.

[This is one CL in a refactoring stack making very small changes
in each step, so that any subtle bugs that we miss can be more
easily pinpointed to a small change.]

Change-Id: I5379122f96d9921ecda7a6a37cabd6c6b4d529a4
Reviewed-on: https://go-review.googlesource.com/c/go/+/564121
Reviewed-by: Ian Lance Taylor <iant@google.com>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>

runtime: merge timerRemoving into timerModifying

timerRemoving is just a kind of "locked for modification",
so merge it into timerModifying. This does potentially remove
a fast path from deltimer, in that deltimer of timerRemoving
is a fast-path exit while deltimer of timerModifying has to
wait for the timer to settle. Since all the timerModifying
critical paths are bounded and short, this should not matter.

This is part of a larger simplification of the state set.

[This is one CL in a refactoring stack making very small changes
in each step, so that any subtle bugs that we miss can be more
easily pinpointed to a small change.]

Change-Id: I039bf6a5a041a158dc3d1af8127f28eed50fc540
Reviewed-on: https://go-review.googlesource.com/c/go/+/564120
Reviewed-by: Ian Lance Taylor <iant@google.com>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>

runtime: merge timerModifiedEarlier and timerModifierLater

Nothing actually needs to know the difference between these
two states, so merge them.

This is part of a larger simplification of the state set.

[This is one CL in a refactoring stack making very small changes
in each step, so that any subtle bugs that we miss can be more
easily pinpointed to a small change.]

Change-Id: Ia30699ac92e66467773942e7df1fb21470a6e51a
Reviewed-on: https://go-review.googlesource.com/c/go/+/564119
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Reviewed-by: Ian Lance Taylor <iant@google.com>

runtime: delete addtimer

modtimer can always be used in place of addtimer.
Do that and delete addtimer, avoiding duplicated logic.

[This is one CL in a refactoring stack making very small changes
in each step, so that any subtle bugs that we miss can be more
easily pinpointed to a small change.]

Change-Id: I70291796bdac3bef5e0850f039f6f4a1da4498ae
Reviewed-on: https://go-review.googlesource.com/c/go/+/564118
Reviewed-by: Ian Lance Taylor <iant@google.com>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>

runtime: move all timer-locking code into time.go

No code changes, only code moves here.
Move all code that locks pp.timersLock into time.go
so that it is all in one place, for easier abstraction.

[This is one CL in a refactoring stack making very small changes
in each step, so that any subtle bugs that we miss can be more
easily pinpointed to a small change.]

Change-Id: I1b59af7780431ec6479440534579deb1a3d9d7a3
Reviewed-on: https://go-review.googlesource.com/c/go/+/564117
Reviewed-by: Ian Lance Taylor <iant@google.com>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>

runtime: delete clearDeletedTimers

adjusttimers already contains the same logic. Use it instead.
This avoids having two copies of the code and is faster.

adjusttimers was formerly O(n log n) but is now O(n).
clearDeletedTimers was formerly O(n² log n) and is now gone!

[This is one CL in a refactoring stack making very small changes
in each step, so that any subtle bugs that we miss can be more
easily pinpointed to a small change.]

Change-Id: I32bf24817a589033dc304b359f8df10ea21f48fc
Reviewed-on: https://go-review.googlesource.com/c/go/+/564116
Reviewed-by: Ian Lance Taylor <iant@google.com>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>

runtime: simplify, speed up adjusttimers

The current adjusttimers does an O(n) loop and then queues
a bunch of reinsertions, each of which is O(log n), for a worst
case of O(n log n) time plus an allocation of n elements.

Reestablishing the heap invariant from an arbitrarily ordered
slice can be done in O(n) time, so it is both simpler and faster
to avoid the allocated temporary queue and just re-init the
heap if we have damaged it. The cost of doing so is no worse
than the O(n) loop we already did.

This change also avoids holding multiple timers locked (status
set to timerMoving) at any given moment, as well as holding
individual timers locked for unbounded amounts of time,
as opposed to fixed-size critical sections.

[This is one CL in a refactoring stack making very small changes
in each step, so that any subtle bugs that we miss can be more
easily pinpointed to a small change.]

Change-Id: If966c1d1e66db797f4b19e7b1abbc06ab651764d
Reviewed-on: https://go-review.googlesource.com/c/go/+/564115
Reviewed-by: Ian Lance Taylor <iant@google.com>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>

go/build: add check for allowed vendor packages

Add a test that checks that all vendored packages in both src/ and
src/cmd are on an allowlist.

For #65678.

Change-Id: Ie9982f8b69c9c0fc6fef41c9dadeb464ecd7781a
Reviewed-on: https://go-review.googlesource.com/c/go/+/564355
Reviewed-by: Bryan Mills <bcmills@google.com>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Reviewed-by: Dmitri Shuralyov <dmitshur@golang.org>
Reviewed-by: Dmitri Shuralyov <dmitshur@google.com>

cmd/go: fix TestScript/mod_vendor_goversion for CL 567476

Change-Id: I00b9934a4942a662a2eb14941c9d07e8750aa1b5
Reviewed-on: https://go-review.googlesource.com/c/go/+/567815
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Auto-Submit: Russ Cox <rsc@golang.org>
Reviewed-by: Robert Findley <rfindley@google.com>

reflect: add Overflow methods to Type

This CL adds new methods synonymous with the method of the same name
in reflect.Value to reflect.Type: OverflowComplex, OverflowFloat, OverflowInt, OverflowUint.

Fixes #60427

Change-Id: I7a0bb35629e59a7429820f13fcd3a6f120194bc6
GitHub-Last-Rev: 26c11bcffe0f418e7d5c37e14587e738d5d939d6
GitHub-Pull-Request: golang/go#65955
Reviewed-on: https://go-review.googlesource.com/c/go/+/567296
Auto-Submit: Ian Lance Taylor <iant@google.com>
Reviewed-by: Dmitri Shuralyov <dmitshur@google.com>
Reviewed-by: Ian Lance Taylor <iant@google.com>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>

cmd/dist: let the three runtime -quick tests run simultaneously

For #65164

Change-Id: Ied19cebd113ef91c34f613cafbeb92a335d6420d
GitHub-Last-Rev: 8118be6e30ffc4edcd88b8a1d5ee3105e2c760de
GitHub-Pull-Request: golang/go#65444
Reviewed-on: https://go-review.googlesource.com/c/go/+/560597
Commit-Queue: Ian Lance Taylor <iant@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Reviewed-by: Keith Randall <khr@google.com>
Reviewed-by: Than McIntosh <thanm@google.com>
Auto-Submit: Ian Lance Taylor <iant@golang.org>

cmd/compile: mark pointer to noalg type as noalg

When the compiler writes PtrToThis field of noalg type, it generates
its pointer type. Mark them as noalg to prevent put them in typelinks.

Fixes #65957

Change-Id: Icbc3b18bc866f9138c7648e42dd500a80326f72b
Reviewed-on: https://go-review.googlesource.com/c/go/+/567335
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
Auto-Submit: Keith Randall <khr@google.com>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Reviewed-by: Keith Randall <khr@google.com>

go/types, types2: move Checker.langCompat from version.go to expr.go (cleanup)

This makes version.go holding core version checking code only.
No functional changes.

Change-Id: Ia88a48166cad2698765697dd7a8625b56ecc2226
Reviewed-on: https://go-review.googlesource.com/c/go/+/567536
Reviewed-by: Robert Griesemer <gri@google.com>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Reviewed-by: Robert Findley <rfindley@google.com>
Auto-Submit: Robert Griesemer <gri@google.com>

go/types, types2: consistently use singular when reporting version errors

Change-Id: I39af932b789cd18dc4bfc84f9667b1c32c9825f4
Reviewed-on: https://go-review.googlesource.com/c/go/+/567476
Reviewed-by: Robert Findley <rfindley@google.com>
Reviewed-by: Robert Griesemer <gri@google.com>
Auto-Submit: Robert Griesemer <gri@google.com>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>

go/types, types2: initial support for parameterized type aliases

Permit type parameters on type alias declarations depending on
Go language version.

Implement various version checks such that at most one version
error is reported per type alias declaration.

Add tparams field to Alias type node.

Missing:
        - instantiation of alias types
        - API additions (requires proposal)

For #46477.

Change-Id: Ica658292bd096d3bceb513027d3353501a6c58e4
Reviewed-on: https://go-review.googlesource.com/c/go/+/566856
Auto-Submit: Robert Griesemer <gri@google.com>
Reviewed-by: Robert Griesemer <gri@google.com>
Reviewed-by: Robert Findley <rfindley@google.com>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>

go/types, types2: separate formatting from error handling functions

This change moves formatting-specific functionality into a new file
format.go and rearranges the code in the errors.go files to be in
the same order for go/types and types2, making them more similar.

No functionality change. This is a pure code reordering.

Change-Id: Ibd818792397be146ad510a6c7308c85d3bb65956
Reviewed-on: https://go-review.googlesource.com/c/go/+/566555
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Auto-Submit: Robert Griesemer <gri@google.com>
Reviewed-by: Robert Findley <rfindley@google.com>
Reviewed-by: Robert Griesemer <gri@google.com>

go/types: generate initorder.go from types2 source

This CL reduces the amount of code that needs to be maintained
manually by about 320 LOC.

Change-Id: Ib797e86dd4abd3a9fe614787103f0e5cebd5e4ae
Reviewed-on: https://go-review.googlesource.com/c/go/+/565838
Reviewed-by: Robert Griesemer <gri@google.com>
Reviewed-by: Robert Findley <rfindley@google.com>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Auto-Submit: Robert Griesemer <gri@google.com>

go/types: generate mono.go from types2 source

This CL reduces the amount of code that needs to be maintained
manually by about 340 LOC.

Change-Id: If7b96c30e5a2f1ff28ebf4ca2f3ac3f73d6a8865
Reviewed-on: https://go-review.googlesource.com/c/go/+/565839
Reviewed-by: Robert Griesemer <gri@google.com>
Auto-Submit: Robert Griesemer <gri@google.com>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Reviewed-by: Robert Findley <rfindley@google.com>

go/types, types2: call error handler for each sub-error as needed

Factor out calling or typechecker error handler from error_.report.
In error_.report, decide if the typechecker error handler needs to
be called once or multiple times.

This change enables the use of sub-errors for types2 and go/types,
with the error handler taking care of deciding how many "separate"
errors are reported via the API.

Use new error reporting in go/types mono and initorder computation;
with the above adjustments, these changes should now pass gopls tests.

Also: adjust some format strings to avoid vet errors.

Change-Id: If05a7044399b4783c596c69a8158619f83c21c70
Reviewed-on: https://go-review.googlesource.com/c/go/+/566537
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Reviewed-by: Robert Findley <rfindley@google.com>
Reviewed-by: Robert Griesemer <gri@google.com>
Auto-Submit: Robert Griesemer <gri@google.com>

net/http/httputil: avoid ReverseProxy data race on 1xx response and error

ReverseProxy uses a httptrace.ClientTrace.Got1xxResponse trace hook
to capture 1xx response headers for proxying. This hook can be called
asynchrnously after RoundTrip returns. (This should only happen when
RoundTrip has failed for some reason.) Add synchronization so we don't
attempt to modifying the ResponseWriter headers map from the hook
after another goroutine has begun making use of it.

Fixes #65123

Change-Id: I8b7ecb1a140f7ba7e37b9d27b8a20bca41a118b1
Reviewed-on: https://go-review.googlesource.com/c/go/+/567216
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Reviewed-by: Jonathan Amsterdam <jba@google.com>
Auto-Submit: Damien Neil <dneil@google.com>

slices: Delete clears the tail when j == len(s)

Fixes #65669

Change-Id: Ifd2011dd604fef399e4352b804fc2f6a9e74096e
Reviewed-on: https://go-review.googlesource.com/c/go/+/566237
Reviewed-by: Ian Lance Taylor <iant@google.com>
Reviewed-by: Keith Randall <khr@google.com>
Auto-Submit: Keith Randall <khr@golang.org>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Reviewed-by: Keith Randall <khr@golang.org>

cmd/compile: fix early deadcode with label statement

CL 517775 moved early deadcode into unified writer. with new way to
handle dead code with label statement involved: any statements after
terminating statement will be considered dead until next label
statement.

However, this is not safe, because code after label statement may still
refer to dead statements between terminating and label statement.

It's only safe to remove statements after terminating *and* label one.

Fixes #65593

Change-Id: Idb630165240931fad50789304a9e4535f51f56e2
Reviewed-on: https://go-review.googlesource.com/c/go/+/565596
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Reviewed-by: Keith Randall <khr@google.com>
TryBot-Result: Gopher Robot <gobot@golang.org>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
Run-TryBot: Cuong Manh Le <cuong.manhle.vn@gmail.com>
Auto-Submit: Cuong Manh Le <cuong.manhle.vn@gmail.com>

runtime: use MapMaxKeyBytes,MapMaxElemBytes,MapBucketCount of internal/abi

For #59670

Change-Id: I9265e033bf3a84c3dc7b4a5d52c0df9672435f0d
GitHub-Last-Rev: 8e4099095cec9e774abe9b72212a1eab6f6f9fdb
GitHub-Pull-Request: golang/go#64774
Reviewed-on: https://go-review.googlesource.com/c/go/+/550117
Reviewed-by: Keith Randall <khr@golang.org>
Reviewed-by: Keith Randall <khr@google.com>
Reviewed-by: Than McIntosh <thanm@google.com>
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runtime: fix the potential race of idle P's during injectglist

Fixes #63555

Change-Id: I26e7baf58fcb78e66e0feed5725e371e25d657cc
Reviewed-on: https://go-review.googlesource.com/c/go/+/550175
Reviewed-by: Michael Pratt <mpratt@google.com>
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Reviewed-by: Carlos Amedee <carlos@golang.org>

runtime: don't clobber saved frame pointer during arm64 racecall

During calls to the race detector on arm64, we switch to the g0 stack if
we aren't already on it. If we are already on the g0 stack, the race
detector library code can then create a stack frame using the stack
pointer coming from Go code. The race detector library can go on to
write values to the top of its stack frame. But the Go ABI for arm64
saves the caller's frame pointer in the word below the current stack
frame. So, the saved frame pointer on the stack can be clobbered by the
race detector. Decrement the stack pointer to account for where the
frame pointer is saved, like we do for asmcgocall.

Change-Id: I66e5e4a671c3befc10776bac6869810ecf71790d
Reviewed-on: https://go-review.googlesource.com/c/go/+/561515
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Reviewed-by: Keith Randall <khr@golang.org>
Auto-Submit: Keith Randall <khr@google.com>
Reviewed-by: Keith Randall <khr@google.com>
Reviewed-by: Michael Knyszek <mknyszek@google.com>

runtime: disable use of runnext on wasm

When readying a goroutine, the scheduler typically places the readied
goroutine in pp.runnext, which will typically be the next goroutine to
run in the schedule.

In order to prevent a set of ping-pong goroutines from simply switching
back and forth via runnext and starving the rest of the run queue, a
goroutine scheduled via runnext shares a time slice (pp.schedtick) with
the previous goroutine.

sysmon detects "long-running goroutines", which really means Ps using
the same pp.schedtick for too long, and preempts them to allow the rest
of the run queue to run. Thus this avoids starvation via runnext.

However, wasm has no threads, and thus no sysmon. Without sysmon to
preempt, the possibility for starvation returns. Avoid this by disabling
runnext entirely on wasm. This means that readied goroutines always go
on the end of the run queue and thus cannot starve via runnext.

Note that this CL doesn't do anything about single long-running
goroutines. Without sysmon to preempt them, a single goroutine that
fails to yield will starve the run queue indefinitely.

For #65178.

Change-Id: I10859d088776125a2af8c9cd862b6e071da628b5
Cq-Include-Trybots: luci.golang.try:gotip-js-wasm,gotip-wasip1-wasm_wasmtime,gotip-wasip1-wasm_wazero
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cmd/compile/internal/noder: add method wrapper comments

Add commentary explaining why and how we create method wrappers.

Change-Id: Idf35a77d0483f24c2163e11f5e001fd5536cca63
Reviewed-on: https://go-review.googlesource.com/c/go/+/558395
Auto-Submit: Matthew Dempsky <mdempsky@google.com>
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Reviewed-by: Cuong Manh Le <cuong.manhle.vn@gmail.com>
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net: Correct the code snippet erroneously rolled back in CL550435

In CL https://golang.org/cl/550435, a segment that had already been reviewed and modified was rolled back due to an erroneous operation. Here, submit a correct code snippet.

Change-Id: I46adfad110d532aec5f557c350fe6dccbc583968
Reviewed-on: https://go-review.googlesource.com/c/go/+/565628
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Reviewed-by: Damien Neil <dneil@google.com>
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Reviewed-by: Carlos Amedee <carlos@golang.org>
Reviewed-by: Mateusz Poliwczak <mpoliwczak34@gmail.com>
Auto-Submit: Ian Lance Taylor <iant@golang.org>
Commit-Queue: Ian Lance Taylor <iant@golang.org>

net/http: prevent redirect loop in serveFile if "/" is a normal file

When FileServer(Dir("file")) is used where "file" is a normal file and
not a directory, the server enters a redirect loop.

The usage of a file inplace of a directory path is not documented in
http.Dir and it could be considered undefined behavior.

This CL updates serveFile to check if we are trying to traverse a normal
file instead of a directory and return an error, preventing the redirect
loop.

Fixes #63769

Change-Id: I81e289444e7d0bd72189c2e7b763f5540333e2d0
GitHub-Last-Rev: 754c9a1167916b5a8c3c827391d7e4a2ff3bc44d
GitHub-Pull-Request: golang/go#63860
Reviewed-on: https://go-review.googlesource.com/c/go/+/538719
Reviewed-by: Damien Neil <dneil@google.com>
Reviewed-by: Emmanuel Odeke <emmanuel@orijtech.com>
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Commit-Queue: Bryan Mills <bcmills@google.com>

net/http/pprof: avoid panic with user-defined "GET /" route

With the new routing style in go 1.22, declaring

    http.Handle("GET /", h)

generates a conflict with route "/debug/pprof/" and the others declared in
the net/http/pprof package. You get an error such as:

panic: pattern "GET /" (registered at .../pprof.go:94): GET / matches
fewer methods than /debug/pprof/, but has a more general path pattern

This patch prevents that error.  Adding GET is correct because no other
method makes sense with the /debug/pprof routes. However, a tool using any
method other than GET will break.

We preserve the traditional behaviour when GODEBUG=httpmuxgo121=1 is
specified.

Updates #65723

Change-Id: I49c21f5f3e802ad7538062d824354b2e4d8a800e
GitHub-Last-Rev: 35e4012663f454fee8f00a321c43592ce4754feb
GitHub-Pull-Request: golang/go#65791
Reviewed-on: https://go-review.googlesource.com/c/go/+/565176
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Reviewed-by: Carlos Amedee <carlos@golang.org>

cmd/internal, cmd/link: unify the relocation naming style of loong64

Change-Id: I2990701e71a63af7bdd6851b6008dc63cb1c1a83
Reviewed-on: https://go-review.googlesource.com/c/go/+/535616
Reviewed-by: abner chenc <chenguoqi@loongson.cn>
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Reviewed-by: sophie zhao <zhaoxiaolin@loongson.cn>
Reviewed-by: Cherry Mui <cherryyz@google.com>
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go/types: added test case for Checker.CheckExpr

For #65898.

Change-Id: I495e53060ac56b88a551ccd9901f25bbce97c714
Reviewed-on: https://go-review.googlesource.com/c/go/+/567215
Reviewed-by: Alan Donovan <adonovan@google.com>
Reviewed-by: Robert Findley <rfindley@google.com>
Reviewed-by: Robert Griesemer <gri@google.com>
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os: avoid GetFileInformationByHandleEx call when stat'ing files on Windows

os.Stat and os.Lstat on Windows use GetFileInformationByHandleEx to
retrieve file information for reparse points and files that
GetFileAttributesEx does not handle.

However, GetFileInformationByHandleEx is only necessary for
reparse points, so we can avoid the call for regular files.

With this change we can drop the FAT hack that was added in CL 154377,
as files won't have the FILE_ATTRIBUTE_REPARSE_POINT attribute set
on that file system.

Change-Id: Id18639067a6c3fa1bb2c6706d5b79358c224fe37
Reviewed-on: https://go-review.googlesource.com/c/go/+/566397
Reviewed-by: Carlos Amedee <carlos@golang.org>
Reviewed-by: Alex Brainman <alex.brainman@gmail.com>
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doc: document os.ModeSocket support on Windows

Updates #33357.

Change-Id: I66866475447e03f604202f34ddfbafdc0512cb72
Reviewed-on: https://go-review.googlesource.com/c/go/+/565135
Reviewed-by: Carlos Amedee <carlos@golang.org>
Reviewed-by: Bryan Mills <bcmills@google.com>
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reflect: fix typo in comment

Change-Id: Ia8e666b128622391d72e42449c01c4e10f3c9e1e
GitHub-Last-Rev: c74cf13b70772a965a14630108544a89690d1383
GitHub-Pull-Request: golang/go#65938
Reviewed-on: https://go-review.googlesource.com/c/go/+/566855
Reviewed-by: Carlos Amedee <carlos@golang.org>
Reviewed-by: qiulaidongfeng <2645477756@qq.com>
Auto-Submit: Ian Lance Taylor <iant@google.com>
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Reviewed-by: Ian Lance Taylor <iant@google.com>

syscall: fix typo in comment

Change-Id: I1804315fd3ec50ab1e3f480efd92c59e36fd47d0
GitHub-Last-Rev: 07d969ab71eabfe7034b62f45a1f4058b66ee014
GitHub-Pull-Request: golang/go#65921
Reviewed-on: https://go-review.googlesource.com/c/go/+/566615
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Reviewed-by: Carlos Amedee <carlos@golang.org>

archive/tar: check returned error before use hdr

Change-Id: I8c28dac73427e37d58d970b00d8f0f1413bede2e
GitHub-Last-Rev: a11a8036028ecf6f811b1470becc924b77a2c734
GitHub-Pull-Request: golang/go#65932
Reviewed-on: https://go-review.googlesource.com/c/go/+/566695
Auto-Submit: Ian Lance Taylor <iant@google.com>
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Reviewed-by: Joseph Tsai <joetsai@digital-static.net>
Reviewed-by: Ian Lance Taylor <iant@google.com>
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html/template: replace bytes.Compare call with bytes.Equal

Change-Id: I1bd3fdf0ceb9a83dbcc07f55b81489eb2c82c9ba
GitHub-Last-Rev: 05d49d7fb921e59529f7105a93b4b7fba51ab525
GitHub-Pull-Request: golang/go#65418
Reviewed-on: https://go-review.googlesource.com/c/go/+/560115
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Reviewed-by: Ian Lance Taylor <iant@google.com>

encoding/xml: remove unnecessary fmt.Sprintf call

Change-Id: Iba6014340d8b697a3a26b35e8d5a702ccf332e10
GitHub-Last-Rev: ef60463c7b98c2bdabe6d04e0f86947b7f395765
GitHub-Pull-Request: golang/go#65872
Reviewed-on: https://go-review.googlesource.com/c/go/+/565841
Reviewed-by: Ian Lance Taylor <iant@google.com>
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database/sql: wrap errors with %w in driverArgsConnLocked

Use fmt.Errorf %w verb to wrap errors in driverArgsConnLocked,
which allows for easier unwrapping and checking of error types.

Add tests in sql_test.go to ensure that Stmt.Exec and Stmt.Query
correctly wrap underlying Valuer errors, adhering to the new change.

Fixes #64707.

Change-Id: Id9f80e265735d0849ee7abba63e58e4c26e658ad
GitHub-Last-Rev: 0df367e0fb5b213513d4e0ab7f5a87984798f96d
GitHub-Pull-Request: golang/go#64728
Reviewed-on: https://go-review.googlesource.com/c/go/+/550116
Reviewed-by: Ian Lance Taylor <iant@google.com>
Reviewed-by: Carlos Amedee <carlos@golang.org>
Reviewed-by: Mauri de Souza Meneguzzo <mauri870@gmail.com>
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cmd/compile: use quotes to wrap user-supplied token

Use quotes to wrap user-supplied token in the syntax error message.
Updates #65790

Change-Id: I631a63df4a6bb8615b7850a324d812190bc15f30
GitHub-Last-Rev: f291e1d5a6adee558d21bb7e0a3a17471bad7eb6
GitHub-Pull-Request: golang/go#65840
Reviewed-on: https://go-review.googlesource.com/c/go/+/565518
Reviewed-by: Carlos Amedee <carlos@golang.org>
Reviewed-by: Robert Griesemer <gri@google.com>
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go/types, types2: fix typo in comment

Change-Id: I410c5fdd9fa3aa7ce5eb1d688621c7684f03a6f9
GitHub-Last-Rev: c3f53de27fb8602b500180242e0be274dc242f8d
GitHub-Pull-Request: golang/go#65950
Reviewed-on: https://go-review.googlesource.com/c/go/+/566858
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Reviewed-by: Robert Griesemer <gri@google.com>
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html/template: escape additional tokens in MarshalJSON errors

Escape "</script" and "<!--" in errors returned from MarshalJSON errors
when attempting to marshal types in script blocks. This prevents any
user controlled content from prematurely terminating the script block.

Fixes #65697

Change-Id: Icf0e26c54ea7d9c1deed0bff11b6506c99ddef1b
Reviewed-on: https://go-review.googlesource.com/c/go/+/564196
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net/http: reject client-side retries in server timeout tests

This breaks an unbounded client-side retry loop if the server's
timeout happens to fire during its final read of the TLS handshake.

The retry loop was observed on wasm platforms at CL 557437.
I was also able to reproduce chains of dozens of retries on my
linux/amd64 workstation by adjusting some timeouts and adding a couple
of sleeps, as in this patch:
https://gist.github.com/bcmills/d0a0a57e5f64eebc24e8211d8ea502b3
However, on linux/amd64 on my workstation the test always eventually
breaks out of the retry loop due to timing jitter.

I couldn't find a retry-specific hook in the http.Client,
http.Transport, or tls.Config structs, so I have instead abused the
Transport.Proxy hook for this purpose. Separately, we may want to
consider adding a retry-specific hook, or changing the net/http
implementation to avoid transparently retrying in this case.

Fixes #65410.
Updates #65178.

Change-Id: I0e43c039615fe815f0a4ba99a8813c48b1fdc7e6
Reviewed-on: https://go-review.googlesource.com/c/go/+/559835
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std: fix more nilness findings

(found with x/tools/go/analysis/passes/nilness)

Change-Id: I1bdc7811efbecea95608e634f894cb6c656e3a5b
Reviewed-on: https://go-review.googlesource.com/c/go/+/564221
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Reviewed-by: Michael Pratt <mpratt@google.com>
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cmd/gofmt: remove impossible err!=nil conditional

Change-Id: Ife63c766cefc14d2f6bdd3c706f913b1b6f99949
GitHub-Last-Rev: 04e23349e68a3ce12b7d33c0fd3ad8c7ffbd8aaa
GitHub-Pull-Request: golang/go#65929
Reviewed-on: https://go-review.googlesource.com/c/go/+/566099
Reviewed-by: Ian Lance Taylor <iant@google.com>
Reviewed-by: Robert Griesemer <gri@google.com>
Reviewed-by: Daniel Martí <mvdan@mvdan.cc>
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net: use bytealg.IndexByte in cgoLookupAddrPTR

Change-Id: I76f4dc1e8bda98936c1198cb45ce8141ca88845b
Reviewed-on: https://go-review.googlesource.com/c/go/+/566235
Auto-Submit: Ian Lance Taylor <iant@google.com>
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crypto/tls: fix typo in comment

Change-Id: I77371ef99797e2b53f1292c9d6a4eb157f116f88
GitHub-Last-Rev: 7ce7d014c0c46b320f9e4b742ae9360d1b5cf4dc
GitHub-Pull-Request: golang/go#65836
Reviewed-on: https://go-review.googlesource.com/c/go/+/565440
Reviewed-by: Ian Lance Taylor <iant@google.com>
Reviewed-by: qiulaidongfeng <2645477756@qq.com>
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Reviewed-by: Carlos Amedee <carlos@golang.org>
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crypto/ecdsa: fix typo

Change-Id: I32580ffb31ffad05a7c8d3aa0c491aff9f55ea6a
GitHub-Last-Rev: 67516eaa18923f0f59a69e82b74ecba74af387d4
GitHub-Pull-Request: golang/go#65565
Reviewed-on: https://go-review.googlesource.com/c/go/+/562316
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os: add available godoc link

Change-Id: I430c9a7c4936d7a8c8c787aa63de9a796d20fdf3
Reviewed-on: https://go-review.googlesource.com/c/go/+/539597
Reviewed-by: Carlos Amedee <carlos@golang.org>
Auto-Submit: Ian Lance Taylor <iant@google.com>
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cmd/go: print the package containing the unmatched embed patterns

Fixes #49534

Cq-Include-Trybots: luci.golang.try:gotip-linux-amd64-longtest,gotip-windows-amd64-longtest
Change-Id: Ia95868ecc1c3dc9715c0fdc7ab1f30348fffaef5
Reviewed-on: https://go-review.googlesource.com/c/go/+/540017
Auto-Submit: Bryan Mills <bcmills@google.com>
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Reviewed-by: Carlos Amedee <carlos@golang.org>
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syscall: add available godoc link

Change-Id: I0fcb79f471cdb8b464924d9b04c675f120861f67
Reviewed-on: https://go-review.googlesource.com/c/go/+/539835
Reviewed-by: Ian Lance Taylor <iant@google.com>
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text: add available godoc link

Change-Id: Idbc110cfc4fd6bbbc8b79807ac14abf7b30e0e65
Reviewed-on: https://go-review.googlesource.com/c/go/+/539855
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regexp: add available godoc link

Signed-off-by: cui fliter <imcusg@gmail.com>
Change-Id: I85339293d4cfb691125f991ec7162e9be186efdc
Reviewed-on: https://go-review.googlesource.com/c/go/+/539599
Reviewed-by: Michael Pratt <mpratt@google.com>
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sync: add available godoc link

Change-Id: I9bc5fd29b0eec8ceadcfee2116de5e7524ef92c2
Reviewed-on: https://go-review.googlesource.com/c/go/+/539617
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doc/next: add the missing slashes ahead of net#Dialer and net#ListenConfig

Change-Id: I216189f181ee73d16602c5cc86eb4d6b439a142b
Reviewed-on: https://go-review.googlesource.com/c/go/+/566595
Reviewed-by: Damien Neil <dneil@google.com>
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Reviewed-by: Ian Lance Taylor <iant@google.com>
Auto-Submit: Damien Neil <dneil@google.com>

crypto/x509: fix typo

Change-Id: I0911c59280e4a208a3deee1f70b47adc60fb734b
GitHub-Last-Rev: 12e95ade68c2f2dd8f87126eae9f3a75841ec8bc
GitHub-Pull-Request: golang/go#65833
Reviewed-on: https://go-review.googlesource.com/c/go/+/565439
Reviewed-by: Michael Pratt <mpratt@google.com>
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net/netip: introduce parsePrefixError for better error handling

Refactor ParsePrefix to return a parsePrefixError containing the input
string and a detailed message on failure, improving error context and
maintaining consistent error formatting within the netip package.

Change-Id: I8d9fb2f833b0f96f43a14622e66e225b54440410
GitHub-Last-Rev: e17bec3afa4efd6c52463bb93e8f694b42c0c2b7
GitHub-Pull-Request: golang/go#65798
Reviewed-on: https://go-review.googlesource.com/c/go/+/565275
Auto-Submit: Michael Pratt <mpratt@google.com>
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Reviewed-by: Damien Neil <dneil@google.com>
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net: don't force cgo resolver for .local subdomain queries

The cgo resolver sends DNS queries for .local subdomain
lookups, just as we do in the go resolver.
We don't need to fallback to the cgo resolver for this
domains when nsswitch.conf uses only file and dns modules.

This has a benefit that we select a consistent resolver,
that is only based on the system configuration, regardless
of the queried domain.

Updates #63978

Change-Id: I9166103adb94d7ab52992925f413f361130e7c52
GitHub-Last-Rev: e2bc5874cb5c9165e3cc058e9effe36d0ce68cd6
GitHub-Pull-Request: golang/go#63986
Reviewed-on: https://go-review.googlesource.com/c/go/+/540555
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time: use bytealg.IndexByte in byteString

Change-Id: I0d42bca7c6ee63c05a0ca09c165f2f591edf7c34
Reviewed-on: https://go-review.googlesource.com/c/go/+/565356
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Auto-Submit: Tobias Klauser <tobias.klauser@gmail.com>

cmd/compile/internal/dwarfgen: refactor putvar and putAbstractVar

Currently, changing putvar or putAbstractVar involves:

1. changing the abbrevs array to add new abbrevs or modify existing ones
2. changing the DW_ABRV_XXX const block to add the new abbrevs, this const
   block must match the changes to the abbrevs array
3. change the code at the start of putvar and putAbstractVar that selects
   the abbrev to use
4. change the body of putvar/putAbstractVar to emit the right attributes in
   the right sequence

Each change must agree with all other, this is error prone and if an mistake
is made there is no compile time or runtime check detecting it. Erroneous
code will simply produce unreadable debug sections.

This commit adds a mechanism to automatically generate code for abbrev
selection as well as the abbrev definitions based on static examination of
the body of putvar and putAbstractVar.

TestPutVarAbbrevGenerator is responsible for checking that the generated
code is kept updated and will regenerated it by passing the '-generate'
option to it.

benchstat output:

                         |    old.txt    |               new.txt                |
                         |    sec/op     |    sec/op      vs base               |
Template                    153.8m ±  6%    153.0m ±  6%       ~ (p=0.853 n=10)
Unicode                     98.98m ± 19%   100.22m ± 15%       ~ (p=0.796 n=10)
GoTypes                    1013.7m ± 13%    943.6m ±  8%       ~ (p=0.353 n=10)
Compiler                    98.48m ± 10%    97.79m ±  6%       ~ (p=0.353 n=10)
SSA                          8.921 ± 31%     6.872 ± 37%       ~ (p=0.912 n=10)
Flate                       114.3m ± 21%    128.0m ± 36%       ~ (p=0.436 n=10)
GoParser                    219.0m ± 27%    214.9m ± 26%       ~ (p=0.631 n=10)
Reflect                     447.5m ± 20%    452.6m ± 22%       ~ (p=0.684 n=10)
Tar                         166.9m ± 27%    166.2m ± 27%       ~ (p=0.529 n=10)
XML                         218.6m ± 25%    219.3m ± 24%       ~ (p=0.631 n=10)
LinkCompiler                492.7m ± 12%    523.2m ± 13%       ~ (p=0.315 n=10)
ExternalLinkCompiler         1.684 ±  3%     1.684 ±  2%       ~ (p=0.684 n=10)
LinkWithoutDebugCompiler    296.0m ±  8%    304.9m ± 12%       ~ (p=0.579 n=10)
StdCmd                       69.59 ± 15%     70.76 ± 14%       ~ (p=0.436 n=10)
geomean                     516.0m          511.5m        -0.87%

                         |   old.txt    |               new.txt               |
                         | user-sec/op  | user-sec/op   vs base               |
Template                   281.5m ± 10%   269.6m ± 13%       ~ (p=0.315 n=10)
Unicode                    107.3m ±  8%   110.2m ±  8%       ~ (p=0.165 n=10)
GoTypes                     2.414 ± 16%    2.181 ±  9%       ~ (p=0.315 n=10)
Compiler                   116.0m ± 16%   119.1m ± 11%       ~ (p=0.971 n=10)
SSA                         25.47 ± 39%    17.75 ± 52%       ~ (p=0.739 n=10)
Flate                      205.2m ± 25%   256.2m ± 43%       ~ (p=0.393 n=10)
GoParser                   456.8m ± 28%   427.0m ± 24%       ~ (p=0.912 n=10)
Reflect                    960.3m ± 22%   990.5m ± 23%       ~ (p=0.280 n=10)
Tar                        299.8m ± 27%   307.9m ± 27%       ~ (p=0.631 n=10)
XML                        425.0m ± 21%   432.8m ± 24%       ~ (p=0.353 n=10)
LinkCompiler               768.1m ± 11%   796.9m ± 14%       ~ (p=0.631 n=10)
ExternalLinkCompiler        1.713 ±  5%    1.666 ±  4%       ~ (p=0.190 n=10)
LinkWithoutDebugCompiler   313.0m ±  9%   316.7m ± 12%       ~ (p=0.481 n=10)
geomean                    588.6m         579.5m        -1.55%

          |   old.txt    |                new.txt                |
          |  text-bytes  |  text-bytes   vs base                 |
HelloSize   842.9Ki ± 0%   842.9Ki ± 0%       ~ (p=1.000 n=10) ¹
CmdGoSize   10.95Mi ± 0%   10.95Mi ± 0%       ~ (p=1.000 n=10) ¹
geomean     3.003Mi        3.003Mi       +0.00%
¹ all samples are equal

          |   old.txt    |                new.txt                |
          |  data-bytes  |  data-bytes   vs base                 |
HelloSize   15.08Ki ± 0%   15.08Ki ± 0%       ~ (p=1.000 n=10) ¹
CmdGoSize   314.7Ki ± 0%   314.7Ki ± 0%       ~ (p=1.000 n=10) ¹
geomean     68.88Ki        68.88Ki       +0.00%
¹ all samples are equal

          |   old.txt    |                new.txt                |
          |  bss-bytes   |  bss-bytes    vs base                 |
HelloSize   396.8Ki ± 0%   396.8Ki ± 0%       ~ (p=1.000 n=10) ¹
CmdGoSize   428.8Ki ± 0%   428.8Ki ± 0%       ~ (p=1.000 n=10) ¹
geomean     412.5Ki        412.5Ki       +0.00%
¹ all samples are equal

          |   old.txt    |               new.txt               |
          |  exe-bytes   |  exe-bytes    vs base               |
HelloSize   1.310Mi ± 0%   1.310Mi ± 0%  -0.01% (p=0.000 n=10)
CmdGoSize   16.37Mi ± 0%   16.37Mi ± 0%  -0.00% (p=0.000 n=10)
geomean     4.631Mi        4.631Mi       -0.00%

Change-Id: I7edf37b5a47fd9aceef931ddf2c701e66a7b38b2
Reviewed-on: https://go-review.googlesource.com/c/go/+/563815
Reviewed-by: Michael Pratt <mpratt@google.com>
Reviewed-by: Than McIntosh <thanm@google.com>
Auto-Submit: Michael Pratt <mpratt@google.com>
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sync: simplify the code with atomic.Pointer

Change-Id: I79797be6b385c9927d68350334d7f7387007085f
GitHub-Last-Rev: 3daa3b144f55f527d183d4ff35475ca4af3ee143
GitHub-Pull-Request: golang/go#65937
Reviewed-on: https://go-review.googlesource.com/c/go/+/566815
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Reviewed-by: Ian Lance Taylor <iant@google.com>

path/filepath: add Localize

Add the Localize function, which takes an io/fs slash-separated path
and returns an operating system path.

Localize returns an error if the path cannot be represented on
the current platform.

Replace internal/safefile.FromFS with Localize,
which serves the same purpose as this function.

The internal/safefile package remains separate from path/filepath
to avoid a dependency cycle with the os package.

Fixes #57151

Change-Id: I75c88047ddea17808276761da07bf79172c4f6fc
Reviewed-on: https://go-review.googlesource.com/c/go/+/531677
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net/http: allow multiple spaces between method and path in mux patterns

Fixes #64910

Change-Id: I14fd1e35c95b14591e3ad7b889dc1ab19a008730
GitHub-Last-Rev: b8d436cdee93d103703e7e6d4bb28315c5035300
GitHub-Pull-Request: golang/go#65868
Reviewed-on: https://go-review.googlesource.com/c/go/+/565916
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expvar: avoid conflict with user-defined "GET /" route.

With the new routing style in go 1.22, declaring

    http.Handle("GET /", h)

generates a conflict with route "/debug/vars" declared in the expvar
package. You get an error such as:

panic: pattern "GET /" (registered at ...) conflicts with pattern
"/debug/vars" (registered at ...expvar.go:384): GET / matches fewer
methods than /debug/vars, but has a more general path pattern

This patch prevents that error.  Adding GET is correct because no other
method makes sense with /debug/vars.

We preserve the traditional behaviour when GODEBUG=httpmuxgo121=1 is
specified.

Fixes #65723

Change-Id: Id2b963ebad41a1ebdcceb73baf3436d59aac73a0
GitHub-Last-Rev: 9c2b9f74a7c8a3c756e9948814231b8f4e60b216
GitHub-Pull-Request: golang/go#65745
Reviewed-on: https://go-review.googlesource.com/c/go/+/564735
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runtime/coverage: remove refs to deprecated io/ioutil

Change-Id: I66965e6a61cf1726db06670978a4654b84f3fd72
GitHub-Last-Rev: 90023e48435029c94a316413b30e46c9ce0019d5
GitHub-Pull-Request: golang/go#65900
Reviewed-on: https://go-review.googlesource.com/c/go/+/566356
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Reviewed-by: Ian Lance Taylor <iant@google.com>

path/filepath: support multiple TestAbs runs on Windows

TestAbs modifies the absTests global variable on Windows, which makes
the test to fail if it is run more than once, i.e. executing
"go test -run ^TestAbs$ -count 2 path/filepath".

This CL fixes the issue by clipping the absTests slices before
appending more elements to it.

Change-Id: I8f1144b2f10b8fa1b847e6639c0bda7baafc2dac
Reviewed-on: https://go-review.googlesource.com/c/go/+/566396
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text/template: add "else with" action

Add "else with" action will reduce the template complexity in some use cases(#57646).
This action will be added:
  {{with pipeline}} T1 {{else with pipeline}} T0 {{end}}.

Fixes #57646

Change-Id: I90ed546ab671805f753343b00bd3c9d1a1d5581d
Reviewed-on: https://go-review.googlesource.com/c/go/+/545376
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Reviewed-by: Rob Pike <r@golang.org>
Reviewed-by: Dmitri Shuralyov <dmitshur@google.com>
Reviewed-by: Ian Lance Taylor <iant@google.com>

net/http: make FileServer look good on mobile

Currently when viewing directories on a phone, the text is small and
often hard to tap correctly.  This commit adds the viewport property to
the page to make it look correct on phones.  This commit also makes the
page behave in Standards Mode instead of Quirks Mode which does not
effect the behavior of this page but makes me feel good inside ☺️

Change-Id: I4babcf79085e85fba57453b7a235e4750a269a42
Reviewed-on: https://go-review.googlesource.com/c/go/+/552595
Auto-Submit: Ian Lance Taylor <iant@golang.org>
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net: skip TestReadLine if /etc/services does not exist

Fixes #65905

Change-Id: I42326d3b743e80d5226ea374eca5c9edaef4dd4d
Reviewed-on: https://go-review.googlesource.com/c/go/+/566535
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path/filepath: delete the deprecated joinNonEmpty and isUNC

Change-Id: I4ce88b2e8e8d24afb63ca7246ce0c418fcb02c9e
Reviewed-on: https://go-review.googlesource.com/c/go/+/564715
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go/types: generate errors_test.go from types2 source

This CL reduces the amount of code that needs to be maintained
manually by about 50 LOC.

Change-Id: I022688d6db58bf58e7844487582725a23ca820be
Reviewed-on: https://go-review.googlesource.com/c/go/+/566515
Reviewed-by: Robert Griesemer <gri@google.com>
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go/types, types2: make error handling more similar

This change will make error handling between go/types and types2
more similar which will in turn allow more go/types files to be
generated from types2 sources.

Specifically:
- add Checker.newError to create error_ objects
- s/error_.errorf/error_.addf/
- remove error_.String (use error_.msg instead)
- replace Checker.report with error_.report
- make error_.report as similar as currently possible
- adjust dependencies

The new code consistently uses newError/addf/report
to report all errors.

Change-Id: Ibd6fd743a4f7746b4aa6b93fe768814dad9ee9c0
Reviewed-on: https://go-review.googlesource.com/c/go/+/566096
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runtime: add crash stack support for arm

Change-Id: Ide4002d1cf82f2daaf7261b367c391dedbbf7719
GitHub-Last-Rev: 80ee248c3e34529e7a522acc97db9fb69c82dffb
GitHub-Pull-Request: golang/go#65308
Reviewed-on: https://go-review.googlesource.com/c/go/+/558699
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Revert "os: make use of pidfd on linux"

This reverts CL 528438.

Reason for revert: Implicated in "bad FD" test failures. Full extent of
issue still unclear.

For #62654.
Fixes #65857.

Change-Id: I066e38040544c506917e90255bd0e330964a0276
Reviewed-on: https://go-review.googlesource.com/c/go/+/566477
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Revert "os: make FindProcess use pidfd on Linux"

This reverts CL 542699.

Reason for revert: Some applications assume FindProcess does not return
errors.

For #62654.
Fixes #65866.

Change-Id: Ic185a6253c8e508b08150b618c39a9905f6cdd60
Reviewed-on: https://go-review.googlesource.com/c/go/+/566476
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cmd: don't require build tags in relnote pathnames

Due to a bug in golang.org/x/build/relnote, API features affecting
specific builds would need to include those build tags in relnote
pathnames.

This CL vendors in the fixed golang.org/x/build. (That caused other
modules to be vendored in as well.)

It also renames the syscall relnote file to remove the build tags
from its pathname.

For #64169.

Change-Id: Iaf6cd9099df1156f4e20c63d519a862ea19a7a3b
Reviewed-on: https://go-review.googlesource.com/c/go/+/566455
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math: add round assembly implementations on riscv64

goos: linux
goarch: riscv64
pkg: math
            │ floor_old.bench │           floor_new.bench           │
            │     sec/op      │   sec/op     vs base                │
Ceil              54.12n ± 0%   22.05n ± 0%  -59.26% (p=0.000 n=10)
Floor             40.80n ± 0%   22.05n ± 0%  -45.96% (p=0.000 n=10)
Round             20.73n ± 0%   20.74n ± 0%        ~ (p=0.441 n=10)
RoundToEven       24.07n ± 0%   24.07n ± 0%        ~ (p=1.000 n=10)
Trunc             38.73n ± 0%   22.05n ± 0%  -43.07% (p=0.000 n=10)
geomean           33.58n        22.17n       -33.98%

Change-Id: I24fb9e3bbf8146da253b6791b21377bea1afbd16
Reviewed-on: https://go-review.googlesource.com/c/go/+/504737
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os: avoid writing within the tree during testing CopyFS

Change-Id: I1d3e7c100ddfbd2ea9a7bb9e8efae89893c8365a
Reviewed-on: https://go-review.googlesource.com/c/go/+/566335
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internal/poll: revise the determination about [handled] and improve the code readability for SendFile

There were a bit too many conditional branches in the old code,
resulting in a poor readability. It could be more concise by reducing
and consolidating some of the conditions.

Furthermore, how we've determined whether or not the data transimission
was handled by sendfile(2) seems inappropriate, because it marked the
operation as unhandled whenever any non-retryable error occurs from
calling sendfile(2), it doesn't look like a right approach, at least
this is an inconsistent behavior with what we've done in Splice.

Related to #64044

Change-Id: Ieb65e0879a8841654d0e64a1263a4e43179df1ba
Reviewed-on: https://go-review.googlesource.com/c/go/+/537275
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os: implement CopyFS

Fixes #62484

Change-Id: I5d8950dedf86af48f42a641940b34e62aa2cddcb
Reviewed-on: https://go-review.googlesource.com/c/go/+/558995
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encoding/xml: reject XML declaration after start of document

The XML specification requires an XML declaration, if present, to only
appear at the very beginning of the document, not even preceded by
whitespace. The parser currently accepts it at any part of the input.

Rejecting whitespace at the beginning of the file might break too many
users. This change instead only rejects an XML declaration preceded by
a non-whitespace token *and* allows the Encoder to emit whitespace
before an XML declaration. This means that a token stream produced by
the Decoder can be passed to the Encoder without error, while we still
don't emit clearly invalid XML.

This might break programs depending on Decoder allowing arbitrary XML
before the XML declaration.

Fixes #65691.

Change-Id: Ib1d4b3116aee63f40fd377f90595780b4befd1ee
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internal/trace/v2: make readBatch param more permissive

This function is copied to x/exp/trace. In https://go.dev/cl/566255 a
change is made where the source is a bytes.Reader instead of a
bufio.Reader from one of the two callers. Change the prototype here
instead of diverging the implementations.

Change-Id: I594224663996eadbc8c388442d68ac5706c52c8e
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go/types, types2: remove unreachable func (minor cleanup)

In some places we can't use unreachable() because it does
not terminate control flow and we need to resort to panic.
Be consistent and just use panic("unreachable") everywhere.
This also opens the door to reporting more specific panic
messages.

Mechanical change: s/unreachable()/panic("unreachable")/

Minor cleanup for better consistency.

Change-Id: I6b52af7c21dcfaa1ca19839d14040552db5d4cb4
Reviewed-on: https://go-review.googlesource.com/c/go/+/566135
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go/types: : generate operand.go from types2 source

This CL reduces the amount of code that needs to be maintained
manually by about 400 LOC.

Change-Id: I03f77c8067aebfdb2a1cce6827ded733ff55e1cc
Reviewed-on: https://go-review.googlesource.com/c/go/+/565837
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go/types: : generate assignments.go from types2 source

This CL reduces the amount of code that needs to be maintained
manually by about 600 LOC.

Change-Id: I7107c8050075281bf6840a9f5234d70e09734ce6
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runtime: be careful about crash FD changes during panic

There are two separate cases here:

The base case is simple: a concurrent call to SetCrashOutput while
panicking will switch the crash FD, which could cause the first half of
writes to go to the old FD, and the second half to the new FD. This
isn't a correctness problem, but would be annoying to see in practice.
Since it is easy to check for, I simply drop any changes if panicking is
already in progress.

The second case is more important: SetCrashOutput will close the old FD
after the new FD is swapped, but writeErrData has no locking around use
of the fd, so SetCrashOutput could close the FD out from under
writeErrData, causing lost writes. We handle this similarly, by not
allowing SetCrashOutput to close the old FD if a panic is in progress,
but we have to be more careful about synchronization between
writeErrData and setCrashFD to ensure that writeErrData can't observe
the old FD while setCrashFD allows close.

For #42888.

Change-Id: I7270b2cc5ea58a15ba40145b7a96d557acdfe842
Reviewed-on: https://go-review.googlesource.com/c/go/+/559801
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cmd/fix: support go versions with patch release

Support go version with patch release(e.g. 1.21.0)
and release candidates(e.g. 1.21rc1)
when parsing the go version in the fix command
by using new "go/version" package.

Fixes #62584

Change-Id: I0ec16137c7a396c68039d374c770c4021fb54b4e
GitHub-Last-Rev: 76bced5c48334c0937289bce8bcf50f82e3f0b98
GitHub-Pull-Request: golang/go#62586
Reviewed-on: https://go-review.googlesource.com/c/go/+/527342
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go/doc: fix typo in comment

Change-Id: Idcfd649b8b8c8b47f5622702969bf2d43aa57354
GitHub-Last-Rev: cd38bee1917377a5057d6dd7c911c55e79c59eae
GitHub-Pull-Request: golang/go#65835
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cmd: remove support for GOROOT_FINAL

Fixes #62047

Change-Id: If7811c1eb9073fb09b7006076998f8b2e1810bfb
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runtime: migrate internal/syscall to internal/runtime

For #65355

Change-Id: I5fefe30dcb520159de565e61dafc74a740fc8730
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os: make FindProcess use pidfd on Linux

Amend FindProcess to use pidfdFind, and make it return ErrProcessDone
if pidfdFind is used and the process is not found.

Since this is a change in API, introduce GODEBUG osfinderr=0 setting
to disable the feature.

Change-Id: I724c6f622f0c99f21a70b864cf7cf2b8836869ee
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go/types, types2: handle Alias types in substitution

Fixes #65854.
For #65778. // for x/tools/cmd/gotype

Change-Id: I67d4644b28e831926fc6c233098aa1755c57162f
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