Joel Sing [Mon, 8 Dec 2025 13:11:55 +0000 (00:11 +1100)]
runtime: use atomic C types with atomic C functions
Mark types as _Atomic - fixes breakage introduced in CL 726964
across most LLVM based platforms/builders.
Change-Id: I5e64b9ccb0cf5244977a787a52ee124bc03c10de
Reviewed-on: https://go-review.googlesource.com/c/go/+/728040
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com> Reviewed-by: Dmitri Shuralyov <dmitshur@google.com> Reviewed-by: Michael Knyszek <mknyszek@google.com> Reviewed-by: Cherry Mui <cherryyz@google.com>
Nick Ripley [Sat, 6 Dec 2025 15:09:38 +0000 (10:09 -0500)]
runtime: deflake TestProfBufWakeup
If CI infrastructure is oversubscribed, the profile buffer reader can be
blocked long enough for the status in the traceback to be something like
"[syscall, 3 minutes]", rather than the "[syscall]" we are looking for.
Tweak the regexp to look for the expected state at the beginning of the
status in the brackets.
While we're here, clarify the possible "race" in the test, which has
more to do with failing to catch a buggy implementation rather than
failing for a correct implementation. Ideally if the implementation is
buggy, we should see the t.Errorf at least some of the time, even if we
don't see it in every run.
Change-Id: Iebd5229d338dc3f973349cea6dd84c506a6a6964
Reviewed-on: https://go-review.googlesource.com/c/go/+/727660 Reviewed-by: Michael Knyszek <mknyszek@google.com>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com> Reviewed-by: Dmitri Shuralyov <dmitshur@google.com>
khr@golang.org [Mon, 8 Dec 2025 14:21:39 +0000 (09:21 -0500)]
runtime: mark getfp as nosplit
When compiling with -l, we can't take a stack split here.
Fixes #76702
Change-Id: Ieab1225c6259c7f16bb5188aa84bff615d9db2e5
Reviewed-on: https://go-review.googlesource.com/c/go/+/728060
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Auto-Submit: Keith Randall <khr@golang.org> Reviewed-by: Cherry Mui <cherryyz@google.com> Reviewed-by: Keith Randall <khr@google.com>
Meng Zhuo [Thu, 13 Nov 2025 08:13:31 +0000 (16:13 +0800)]
test/codegen: test negation with add/sub on riscv64
Change-Id: Ic0eca86d3c93707ebd7c716e774ebda55af4f196
Reviewed-on: https://go-review.googlesource.com/c/go/+/703755
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matloob [Fri, 5 Dec 2025 20:25:42 +0000 (15:25 -0500)]
cmd/go: convert some more tests to script tests
Convert more tests to script tests so they can run in parallel with the
rest of the script tests. This CL converts
TestPackageMainTestCompilerFlags, TestGoListTest,
TestListTemplateContextFunction, and TestIssue22588.
Change-Id: I4f8410e85d4811e82d85d884d28a2a0d6a6a6964
Reviewed-on: https://go-review.googlesource.com/c/go/+/727420
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com> Reviewed-by: Michael Matloob <matloob@google.com> Reviewed-by: Alan Donovan <adonovan@google.com>
Alan Donovan [Fri, 5 Dec 2025 17:41:21 +0000 (12:41 -0500)]
cmd/go/internal/vet: skip -fix on pkgs from vendor or non-main mod
This change causes go fix (and go vet -fix) to skip applying fixes
to any package in the vendor/ tree, including the GOROOT vendor
packages that are part of std, and to any package from a non-main
module (since these usually come from the readonly module cache).
+ test
Fixes golang/go#76479
Change-Id: Ifdb73e09fbe413b4d99a92e5081b8ea43460be0b
Reviewed-on: https://go-review.googlesource.com/c/go/+/727300
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Auto-Submit: Alan Donovan <adonovan@google.com>
runtime: don't count nGsyscallNoP for extra Ms in C
In #76435, it turns out that the new metric
/sched/goroutines/not-in-go:goroutines counts C threads that have called
into Go before (on Linux) as not-in-go goroutines. The reason for this
is that the M is still attached to the C thread on Linux as an
optimization, so we don't go through all the trouble of detaching the M
and, of course, decrementing nGsyscallNoP.
There's an easy fix to this accounting issue. The flag on the M,
isExtraInC, says whether a thread with an extra M attached no longer has
any Go on its (logical) stack. When we take the P from an M in this
state, we simply just don't increment nGsyscallNoP. When it calls back
into Go, we similarly skip the decrement to nGsyscallNoP.
This is more efficient than alternatives, like always updating
nGsyscallNoP in cgocallbackg, since that would add a new
read-modify-write atomic onto that fast path. It does mean we count
threads in C with a P still attached as not-in-go, but this transient in
most real programs, assuming the thread indeed does not call back into
Go any time soon.
Fixes #76435.
Change-Id: Id05563bacbe35d3fae17d67fb5ed45fa43fa0548
Reviewed-on: https://go-review.googlesource.com/c/go/+/726964
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com> Reviewed-by: Michael Pratt <mpratt@google.com>
Alan Donovan [Thu, 4 Dec 2025 20:29:49 +0000 (15:29 -0500)]
cmd/go: fix race applying fixes in fix and vet -fix modes
Previously, the cmd/fix tool, which is analogous to a compiler
in a "go fix" or "go vet -fix" build, applied its fixes directly
to source files during the build. However, this led to races
since the edits may in some cases occur concurrently with other
build steps that are still reading those source file.
This change separates the computation of the fixes, which
happens during the build, and applying the fixes, which happens
in a phase after the build.
The unitchecker now accepts a FixArchive file name (see CL 726940).
If it is non-empty, the unitchecker will write the fixed files
into an archive instead of updating them directly.
The vet build sets this option, then reads the produced zip
files in the second phase. The files are saved in the cache;
some care is required to sequence the various cache operations
so that a cache hit has all-or-nothing semantics.
The tweak to vet_basic.txt is a sign that there was a latent
bug, inadvertently fixed by this change: because the old approach
relied on side effects of cmd/fix to mutate files, rather than
the current pure-functional approach of computing fixes which
are then applied as a second pass, a cache hit would cause some
edits not to be applied. Now they are applied.
Fixes golang/go#71859
Change-Id: Ib8e70644ec246dcdb20a90794c11ea6fd420247d
Reviewed-on: https://go-review.googlesource.com/c/go/+/727000
Auto-Submit: Alan Donovan <adonovan@google.com> Reviewed-by: Michael Matloob <matloob@golang.org>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com> Reviewed-by: Michael Matloob <matloob@google.com>
This change expands the Pinner documentation based on a few points of
feedback.
- We need a note that the Pinner has a finalizer.
- We need a note that the Pinner is safe to reuse.
I also added a note that the zero value is ready to use, and expanded
upon the use-cases of a Pinner.
Fixes #76431.
Change-Id: I312385557e67a815db05def02c1b1d7dcaa9d764
Reviewed-on: https://go-review.googlesource.com/c/go/+/726641
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Auto-Submit: Michael Knyszek <mknyszek@google.com> Reviewed-by: Michael Pratt <mpratt@google.com>
Michael Matloob [Thu, 4 Dec 2025 20:32:53 +0000 (15:32 -0500)]
cmd/go/testdata/script: skip vet_cache in short mode
vet_cache uses a clean cache
Change-Id: I68e9f32e60ad228785e9bf28f1c3a42e6a6a6964
Reviewed-on: https://go-review.googlesource.com/c/go/+/726961
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Auto-Submit: Michael Matloob <matloob@golang.org> Reviewed-by: Alan Donovan <adonovan@google.com> Reviewed-by: Michael Matloob <matloob@google.com>
runtime: skip TestArenaCollision if we run out of hints
This seems failure mode seems to have become more common on Windows. I
suspect the randomized heap base address has something to do with it,
but I'm not 100% sure.
What's definitely certain is that we're running out of hints, since
we're seeing failures that mheap_.arenaHints is nil and GetNextArenaHint
doesn't actually check that.
At the very least we can check that and skip. We know that in this case
there's not that much we can do.
Fixes #76566.
Change-Id: I8ccc8994806b6c95e3157eb296b09705637564b3
Reviewed-on: https://go-review.googlesource.com/c/go/+/726527 Reviewed-by: Michael Pratt <mpratt@google.com>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
runtime: relax threadsSlack in TestReadMetricsSched
runtime.GC is called in the test and may spin up GOMAXPROCS
(proportional to the initial count) new threads. We need to be robust to
this, and it happens relatively frequently on some platforms.
We didn't notice this earlier since the heap is so miniscule that
runtime.GC essentially finished instantly without all the threads
getting spun up.
Fixes #76613.
Change-Id: I2af02cb090d5c1c952e4db53ad35895b6f23f638
Reviewed-on: https://go-review.googlesource.com/c/go/+/726642
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com> Reviewed-by: Michael Pratt <mpratt@google.com>
runtime: skip mayMoreStackMove in goroutine leak tests
mayMoreStackMove may introduce more scheduler chaos because of all the
stack movement (not as much as mayMoreStackPreempt) so let's disable the
tests here too, since we have evidence that they can produce false
negatives under this configuration. Though we're not 100% sure why this
is happening yet, let's at least stop the flow of flaky failures.
For #75729.
Change-Id: I16d13dba9a61fbd47563b21cbf188e4754f58213
Reviewed-on: https://go-review.googlesource.com/c/go/+/726526
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com> Reviewed-by: Michael Pratt <mpratt@google.com>
runtime/race: set missing argument frame for ppc64x atomic And/Or wrappers
The ppc64x TSAN wrappers for atomic And/Or did not initialize R6 with the Go argument frame before calling racecallatomic. Since racecallatomic expects R6 to point to the argument list and dereferences it unconditionally, this led to a nil-pointer dereference under -race.
Other atomic TSAN wrappers (Load/Store/Add/Swap/CAS) already set up R6 in the expected way. This change aligns the And/Or wrappers with the rest by adding the missing R6 initialisation.
This keeps the behavior consistent across all atomic operations on ppc64x.
Fixes #76051.
Change-Id: Iaf578449a6171a0c6f7c33ec6f64c1251297ae6d
Cq-Include-Trybots: luci.golang.try:gotip-linux-ppc64_power10,gotip-linux-ppc64_power8,gotip-linux-ppc64le_power8,gotip-linux-ppc64le_power9,gotip-linux-ppc64le_power10
Reviewed-on: https://go-review.googlesource.com/c/go/+/718560 Reviewed-by: Mark Freeman <markfreeman@google.com>
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runtime: reject any goroutine leak test failure that failed to execute
This is far more general than the regexp, which was necessary only
because runTestProg doesn't return the error. This change makes
runTestProg a wrapper function around a function that *does* return the
error.
For #76526.
Change-Id: Ib3daa75eb0fe314a28a7a368474943ba470d0d4d
Reviewed-on: https://go-review.googlesource.com/c/go/+/726525
Auto-Submit: Michael Knyszek <mknyszek@google.com>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com> Reviewed-by: Michael Pratt <mpratt@google.com>
When enabling DIT on ARM64, add speculation barrier instructions to
ensure that subsequent instructions are executed using the updated
DIT state.
See https://developer.apple.com/documentation/xcode/writing-arm64-code-for-apple-platforms#Enable-DIT-for-constant-time-cryptographic-operations
which recommends doing this. The Arm documentation for DIT doesn't tell
you to do this, but it seems prudent.
Change-Id: Idbc87b332650a77b8cb3509c11377bf5c724f3cf
Reviewed-on: https://go-review.googlesource.com/c/go/+/726980
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com> Reviewed-by: Cherry Mui <cherryyz@google.com>
Cuong Manh Le [Fri, 5 Dec 2025 14:49:53 +0000 (21:49 +0700)]
cmd/compile: fix mis-infer bounds in slice len/cap calculations
CL 704875 enhanced prove to infer bounds when index have a relationship
with len(A) - K. However, the change incorrectly infer "K - len(A)" case,
causing wrong bounds information.
Fixing this by matching exactly "len(A) - K" case.
Fixes #76709
Change-Id: Ibeedff55520658401af5bd3aa7e98cc1bcf38fd6
Reviewed-on: https://go-review.googlesource.com/c/go/+/727180 Reviewed-by: Cherry Mui <cherryyz@google.com>
Auto-Submit: Cuong Manh Le <cuong.manhle.vn@gmail.com>
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cuishuang [Thu, 4 Dec 2025 03:39:53 +0000 (11:39 +0800)]
all: fix some comment issues
Change-Id: I5dec35b1432705b3a52859c38e758220282226af
Reviewed-on: https://go-review.googlesource.com/c/go/+/726700
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com> Reviewed-by: Sean Liao <sean@liao.dev>
Auto-Submit: Dmitri Shuralyov <dmitshur@golang.org> Reviewed-by: Cherry Mui <cherryyz@google.com> Reviewed-by: Dmitri Shuralyov <dmitshur@google.com>
The probeSeq doc comment describes the probe sequence as triangular and
gives the formula for terms in the sequence. This formula isn't actually
used in the code, though. List the first few terms of the sequence
explicitly so the connection between the description and the code is
more clear.
Change-Id: I6a6a69648bc94e15df436815c16128ebef3c6eb8
Reviewed-on: https://go-review.googlesource.com/c/go/+/726820
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com> Reviewed-by: Michael Pratt <mpratt@google.com> Reviewed-by: Dmitri Shuralyov <dmitshur@google.com>
- CL 726000: go/analysis/passes/modernize: omitzero: suppress on kubebuilder
- CL 726621: internal/refactor/inline: built-ins may affect inference
- CL 727041: go/analysis/passes/modernize: fix stringscut false positives
- CL 727040: go/analysis/unitchecker: write fixed files to an archive
Fixes #76649.
Fixes #76287.
Fixes #76687.
For #71859.
[git-generate]
go install golang.org/x/build/cmd/updatestd@latest
go install golang.org/x/tools/cmd/bundle@latest
updatestd -goroot=$(pwd) -branch=internal-branch.go1.26-vendor
Change-Id: I0a369ad85b06adab3a977c2c523b8214fb53271a
Reviewed-on: https://go-review.googlesource.com/c/go/+/727022
Auto-Submit: Dmitri Shuralyov <dmitshur@golang.org> Reviewed-by: Dmitri Shuralyov <dmitshur@google.com>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com> Reviewed-by: Alan Donovan <adonovan@google.com>
Michael Matloob [Thu, 4 Dec 2025 19:21:44 +0000 (14:21 -0500)]
cmd/internal/fuzztest: move fuzz tests out of cmd/go test suite
They are very slow: taking them out of the cmd/go test suite makes the
go command tests go from about 80 seconds to run on my system, to about
50 seconds to run.
Change-Id: I19b5c252bd2b6e6d64821cada961ddaa6a6a6964
Reviewed-on: https://go-review.googlesource.com/c/go/+/726960
Auto-Submit: Michael Matloob <matloob@google.com> Reviewed-by: Alan Donovan <adonovan@google.com> Reviewed-by: Michael Matloob <matloob@google.com>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
qmuntal [Wed, 3 Dec 2025 10:20:41 +0000 (11:20 +0100)]
crypto: use rand.IsDefaultReader instead of comparing to boring.RandReader
Several crypto functions accepting a rand parameter skip calling
boringcrypto when the rand is not boring.RandReader.
The new crypto/internal/rand package currently defines its own Reader
that wraps boring.RandReader. That will unintentionally bypass
boringcrypto when used with the aforementioned functions.
Fixes #76672
Change-Id: Ie0c1345530c734a23815f9593590b5d32604f54d
Reviewed-on: https://go-review.googlesource.com/c/go/+/726220 Reviewed-by: Dmitri Shuralyov <dmitshur@google.com> Reviewed-by: Filippo Valsorda <filippo@golang.org> Reviewed-by: Roland Shoemaker <roland@golang.org>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
qmuntal [Wed, 3 Dec 2025 11:32:15 +0000 (12:32 +0100)]
crypto/hpke: remove unused hybridKEM field
hybridKEM.pqGenerateKey is not used anywhere. Having it around
is confusing, as it suggests that the mlkem seed is generated within
the mlkem package, when it is not.
Change-Id: Ie0bdb79d6b774db7b21dfff2b966452463f1ce08
Reviewed-on: https://go-review.googlesource.com/c/go/+/726260 Reviewed-by: Filippo Valsorda <filippo@golang.org>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com> Reviewed-by: Dmitri Shuralyov <dmitshur@google.com> Reviewed-by: Roland Shoemaker <roland@golang.org>
cmd/link: don't update offset of existing ELF section name
Fixes #76656
Change-Id: If2e823ba1577700af00f5883e4ea5c139e4749c1
Reviewed-on: https://go-review.googlesource.com/c/go/+/726100 Reviewed-by: Keith Randall <khr@golang.org> Reviewed-by: Keith Randall <khr@google.com> Reviewed-by: Michael Stapelberg <stapelberg@google.com>
Auto-Submit: Ian Lance Taylor <iant@golang.org>
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doc: pre-announce removal of gotypesalias and asynctimerchan GODEBUG flags
This announcement follows the policy outlined in #76163.
For #76472.
Change-Id: I4299e7f474e314810883dc4f50be6afba8c3e3e7
Reviewed-on: https://go-review.googlesource.com/c/go/+/726020
Auto-Submit: Robert Griesemer <gri@google.com> Reviewed-by: Alan Donovan <adonovan@google.com> Reviewed-by: Robert Griesemer <gri@google.com>
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spec: remove restriction on channel element types for close built-in (bug fix)
The spec states that if the argument type for close is a type parameter,
it's type set must only contain channels and they must all have the same
element type. This latter requirement (all must have the same element
type) was never enforced by the compiler, nor is it important for
correctness or required by the implementation.
This change removes this requirement also in the spec and thus
documents what was always (since 1.18) the case.
Fixes #74034.
Change-Id: If65d50bfb581b7f37999413088d3d3b1820e054a
Reviewed-on: https://go-review.googlesource.com/c/go/+/725923
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Auto-Submit: Robert Griesemer <gri@google.com> Reviewed-by: Robert Findley <rfindley@google.com>
Keith Randall [Tue, 2 Dec 2025 22:22:34 +0000 (14:22 -0800)]
doc: mention stack allocation of slices
Very similar to last release's note.
Change-Id: Ie7afe21d98cee1c9718e53b20e8af8ee18504bb9
Reviewed-on: https://go-review.googlesource.com/c/go/+/725921 Reviewed-by: Dmitri Shuralyov <dmitshur@golang.org> Reviewed-by: Dmitri Shuralyov <dmitshur@google.com> Reviewed-by: Keith Randall <khr@google.com>
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Auto-Submit: Keith Randall <khr@golang.org>
Devon Mar [Tue, 25 Nov 2025 07:38:09 +0000 (07:38 +0000)]
net: parse addresses without separators in ParseMac
IEEE EUI guidelines states that "an EUI-48 can be represented in the IEEE RA
hexadecimal (hex) form with the octets separated by hyphens, or as a pure
base-16 numerical representation without hyphens"
(https://standards.ieee.org/wp-content/uploads/import/documents/tutorials/eui.pdf p.9).
The latter form is used in Azure Instance Metadata Service
(https://github.com/Azure/azure-container-networking/pull/4122) among others.
Fixes #66682
Change-Id: Id66c23d50ebb1fed1f3bdb5cf3822a8fd60b886d
GitHub-Last-Rev: 77900cc1a68cb535b685a63cf84b5413b480df2c
GitHub-Pull-Request: golang/go#76387
Reviewed-on: https://go-review.googlesource.com/c/go/+/722720
Auto-Submit: Damien Neil <dneil@google.com> Reviewed-by: Damien Neil <dneil@google.com> Reviewed-by: Dmitri Shuralyov <dmitshur@google.com>
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khr@golang.org [Mon, 1 Dec 2025 18:32:23 +0000 (10:32 -0800)]
cmd/compile: more generated equality function tests
Change-Id: I05cd103ea8d8bbee0ad907ff3e594de273d49e86
Reviewed-on: https://go-review.googlesource.com/c/go/+/725600 Reviewed-by: Keith Randall <khr@google.com> Reviewed-by: Dmitri Shuralyov <dmitshur@google.com>
Auto-Submit: Keith Randall <khr@google.com>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com> Reviewed-by: Cuong Manh Le <cuong.manhle.vn@gmail.com>
crypto/x509: prevent HostnameError.Error() from consuming excessive resource
Constructing HostnameError.Error() takes O(N^2) runtime due to using a
string concatenation in a loop. Additionally, there is no limit on how
many names are included in the error message. As a result, a malicious
attacker could craft a certificate with an infinite amount of names to
unfairly consume resource.
To remediate this, we will now use strings.Builder to construct the
error message, preventing O(N^2) runtime. When a certificate has 100 or
more names, we will also not print each name individually.
Thanks to Philippe Antoine (Catena cyber) for reporting this issue.
Fixes #76445
Fixes CVE-2025-61729
Change-Id: I6343776ec3289577abc76dad71766c491c1a7c81
Reviewed-on: https://go-internal-review.googlesource.com/c/go/+/3000 Reviewed-by: Neal Patel <nealpatel@google.com> Reviewed-by: Damien Neil <dneil@google.com>
Reviewed-on: https://go-review.googlesource.com/c/go/+/725920 Reviewed-by: Roland Shoemaker <roland@golang.org> Reviewed-by: Dmitri Shuralyov <dmitshur@google.com>
TryBot-Bypass: Dmitri Shuralyov <dmitshur@golang.org>
Robert Griesemer [Thu, 20 Nov 2025 22:05:27 +0000 (14:05 -0800)]
spec: more precise prose for built-in function new
1) explain new(type) (simpler) before new(expr) (more complicated)
2) for new(expr), explain what happens when expr is an untyped bool
3) explain that new(nil) is not permitted
4) streamline examples slightly
Fixes #76122.
Change-Id: I5ddb26bd88241b4b2b9aa9b532a62f7861c2341c
Reviewed-on: https://go-review.googlesource.com/c/go/+/722482
Auto-Submit: Robert Griesemer <gri@google.com>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com> Reviewed-by: Robert Griesemer <gri@google.com> Reviewed-by: Alan Donovan <adonovan@google.com>
Commit-Queue: Robert Griesemer <gri@google.com> Reviewed-by: Ian Lance Taylor <iant@golang.org>
Damien Neil [Mon, 1 Dec 2025 20:28:19 +0000 (12:28 -0800)]
net/http: deflake TestClientConnReserveAndConsume
This test includes an assertion that a client conn's state hook
is called exactly once, but some of the test cases can result in
two events occurring: A request completes and a connection closes.
Change the assertion to just check that the hook is called
at least once.
Fixes #76480
Change-Id: Ie1438581b072b10623eb3d5fe443294a639c9853
Reviewed-on: https://go-review.googlesource.com/c/go/+/725601
Commit-Queue: Damien Neil <dneil@google.com>
Auto-Submit: Damien Neil <dneil@google.com> Reviewed-by: Nicholas Husin <husin@google.com> Reviewed-by: Nicholas Husin <nsh@golang.org>
TryBot-Bypass: Damien Neil <dneil@google.com>
Both CL 723241 and CL 723581 added identical definitions.
Change-Id: I6a6a636c9e5f8c9080b9389ebf9d3f10305d79ac
Reviewed-on: https://go-review.googlesource.com/c/go/+/725661
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com> Reviewed-by: Dmitri Shuralyov <dmitshur@golang.org>
Auto-Submit: Michael Pratt <mpratt@google.com> Reviewed-by: Michael Knyszek <mknyszek@google.com>
胡玮文 [Sun, 23 Nov 2025 18:29:24 +0000 (02:29 +0800)]
internal/runtime/cgroup: lineReader fuzz test
The original unit test is converted to a fuzz test, to be more confident
on future refactors. All sub-tests are converted to seed corpus.
Change-Id: Id0c167ed47729a00ea0614d17746ddcc284697d3
Reviewed-on: https://go-review.googlesource.com/c/go/+/723581
Auto-Submit: Michael Pratt <mpratt@google.com>
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Ian Lance Taylor [Fri, 28 Nov 2025 22:34:06 +0000 (14:34 -0800)]
debug/elf: correct case of DWARF in comment
Change-Id: I5b80b0e3e50fafdb732c732cdae6e2756d919d20
Reviewed-on: https://go-review.googlesource.com/c/go/+/725360 Reviewed-by: Dmitri Shuralyov <dmitshur@google.com> Reviewed-by: Mark Freeman <markfreeman@google.com>
Auto-Submit: Ian Lance Taylor <iant@golang.org> Reviewed-by: Sean Liao <sean@liao.dev>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Brad Fitzpatrick [Wed, 26 Nov 2025 18:11:41 +0000 (10:11 -0800)]
doc/next: clean up some Go 1.26 release notes
The Var.Kind stuff was in Go 1.25.
And the net additions were in the wrong tense and didn't have links.
Change-Id: Ie710e1d41c714fe627a3a21a5afb6b7f78301f68
Reviewed-on: https://go-review.googlesource.com/c/go/+/724780 Reviewed-by: Dmitri Shuralyov <dmitshur@google.com>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Auto-Submit: Dmitri Shuralyov <dmitshur@golang.org> Reviewed-by: Mark Freeman <markfreeman@google.com> Reviewed-by: Dmitri Shuralyov <dmitshur@golang.org>
Pull in the latest published version of github.com/google/pprof
as part of the continuous process of keeping Go's dependencies
up to date.
For #36905.
[git-generate]
cd src/cmd
go get github.com/google/pprof@v0.0.0-20251114195745-4902fdda35c8
go mod tidy
go mod vendor
Change-Id: Id26eb632f637fb2c602d87cb83fdff7f099934ce
Reviewed-on: https://go-review.googlesource.com/c/go/+/725500
Auto-Submit: Dmitri Shuralyov <dmitshur@golang.org>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com> Reviewed-by: Dmitri Shuralyov <dmitshur@google.com> Reviewed-by: Michael Pratt <mpratt@google.com>
The Go 1.26 code freeze has recently started. This is a time to update
all golang.org/x/... module versions that contribute packages to the
std and cmd modules in the standard library to latest master versions.
For #36905.
[git-generate]
go install golang.org/x/build/cmd/updatestd@latest
go install golang.org/x/tools/cmd/bundle@latest
updatestd -goroot=$(pwd) -branch=master
Change-Id: I39c68d4c36d0c83ac07c3cda3c4d042bb32a9624
Reviewed-on: https://go-review.googlesource.com/c/go/+/725480
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cmd$ go get golang.org/x/tools@1ad6f3d
cmd$ GOWORK=off go mod tidy
cmd$ GOWORK=off go mod vendor
This merge pulls in the following commits, which include several fixes
needed for go1.26, marked by an asterisk. None of the unmarked commits
affects vendored packages, so it is safe (and simpler) to merge rather
than cherrypick via a release branch.
tools$ git log --oneline 68724afed209...1ad6f3d02713
*4a3f2f81eb go/analysis/passes/printf: panic when function literal is assigned to the blank identifier
*d5d7d21fe7 gopls/internal/cache: fix %q verb use with wrong type
*92a094998a go/analysis/passes/modernize: rangeint: handle usages of loop label
*ffbdcac342 go/analysis/passes/modernize: stditerators: add reflect iters
*2e3e83a050 internal/refactor/inline: preserve local package name used by callee d32ec34454 gopls/internal/protocol/generate: move injections to tables.go 98d172d8bd gopls/internal/protocol: add form field in type CodeAction e1317381e4 go/packages: suppress test on (e.g.) wasm
*e31ed53b51 internal/stdlib: regenerate
*6f1f89817d internal/analysis/driverutil: include end positions in -json output 7839abf5e8 gopls/internal/metadata: document when Module can be nil 98aa9a7d0b gopls/internal/cache: make unimported completions deterministic 4c5faddb0f internal/modindex: unescape import paths c2c902c441 gopls/completion: avoid nil dereference
*4bf3169c8a go/analysis/passes/modernize: waitgroup: highlight "go func" part ba5189b063 gopls/internal/template: fix printf mistake in test
*a7d12506a0 go/analysis/passes/printf: clarify checkForward c7a1a29f93 internal/pkgbits: fix printf mistake in test af205c0a29 gopls/doc/release/v0.21.0.md: tweaks
Change-Id: I23c991987afeb2db3e0f98f76f8ee5000c8a6e02
Reviewed-on: https://go-review.googlesource.com/c/go/+/725460
Auto-Submit: Alan Donovan <adonovan@google.com>
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Commit-Queue: Alan Donovan <adonovan@google.com>
debug/elf: make check for empty symbol section consistent for 64-bit and 32-bit binaries
The check for whether a binary's symbols section is empty is
inconsistent across the 32-bit and 64-bit flows.
Change-Id: I1abc235320a53cf957cfb83c9e7bcad6e52bc529
GitHub-Last-Rev: f264915ca2964ad8f34ce1deee4f42c2f9dc21bf
GitHub-Pull-Request: golang/go#75334
Reviewed-on: https://go-review.googlesource.com/c/go/+/702195
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Cuong Manh Le [Fri, 28 Nov 2025 10:19:42 +0000 (17:19 +0700)]
cmd/compile: avoid unnecessary interface conversion in bloop
Fixes #76482
Change-Id: I076568d8ae92ad6c9e0a5797cfe5bbfb615f63d2
Reviewed-on: https://go-review.googlesource.com/c/go/+/725180
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Auto-Submit: Cuong Manh Le <cuong.manhle.vn@gmail.com>
Daniel Morsing [Thu, 27 Nov 2025 06:45:20 +0000 (06:45 +0000)]
runtime/secret: reorganize tests to fix -buildmode=shared
The testing assembly methods had a linkname that was implicitly
satisfied during the regular build but not there during the shared
build. Fix by moving the testing routine into the package itself.
For good measure, section off the assembly files from the non-experiment
build. Should prevent further build failures as we work on this.
Cq-Include-Trybots: luci.golang.try:gotip-linux-amd64-longtest,gotip-linux-arm64-longtest
Change-Id: I2b45668e44641ae7880ff14f6402d982c7eaedd7
Reviewed-on: https://go-review.googlesource.com/c/go/+/724001 Reviewed-by: David Chase <drchase@google.com>
Auto-Submit: Filippo Valsorda <filippo@golang.org> Reviewed-by: Filippo Valsorda <filippo@golang.org>
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胡玮文 [Sat, 22 Nov 2025 03:00:47 +0000 (11:00 +0800)]
internal/runtime/cgroup: stricter unescapePath
8 and 9 in escape sequence is invalid now, it should be octal.
Escape sequence larger than \377 is invalid now, it does not fit one
byte.
Change-Id: I3fdebce1d054c44919f0e66a33c778b5a2b099e2
Reviewed-on: https://go-review.googlesource.com/c/go/+/723242 Reviewed-by: Dmitri Shuralyov <dmitshur@google.com> Reviewed-by: Michael Pratt <mpratt@google.com>
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Auto-Submit: Dmitri Shuralyov <dmitshur@google.com>
胡玮文 [Fri, 21 Nov 2025 17:44:14 +0000 (01:44 +0800)]
internal/runtime/cgroup: fix path on non-root mount point
We should trim the mount root (4th field in /proc/self/mountinfo) from
cgroup path read from /proc/self/cgroup before appending it to the mount
point. Non-root mount points are very common in containers with cgroup
v1.
parseCPURelativePath is renamed to parseCPUCgroup, as it is unclear what
it is relative to. cgroups(7) says "This pathname is relative to the
mount point of the hierarchy." It should mean the root of the hierarchy,
and we cannot concat it to arbirary cgroup mount point. So just use the
word cgroup, since it parses /proc/self/cgroup.
It now returns errMalformedFile if the cgroup pathname does not start
with "/", and errPathTooLong if the pathname can't fit into the buffer.
We already rely on this when composing the path, just make this explicit
to avoid incorrect paths.
We now parse cgroup first then parse the mount point accordingly. We
consider the previously read cgroup pathname and version to ensure we
got the desired mount point. The out buffer is reused to pass in the
cgroup, to avoid extra memory allocation.
This should also resolve the race mentioned in the comments, so removing
those comments. If our cgroup changed between the two read syscalls, we
will stick with the cgroup read from /proc/self/cgroup. This is the same
behavior as cgroup change after FindCPU() returns, so nothing special to
comment about now.
parseCPUMount now returns error when the combined path is too long, to
avoid panic or truncation if we got a really long path from mountinfo.
cgrouptest is changed to use dev returned from stat() to detect
filesystem boundary, since we don't return mount point and sub-path
separately now. This also avoid using os.Root since we don't handle
untrusted input here. os.Root is too complex, and the performance is
bad.
Fixes #76390
Change-Id: Ia9cbd7be3e58a2d51caf27a973fbd201dac06afc
Reviewed-on: https://go-review.googlesource.com/c/go/+/723241 Reviewed-by: Michael Pratt <mpratt@google.com> Reviewed-by: Dmitri Shuralyov <dmitshur@google.com>
Auto-Submit: Michael Knyszek <mknyszek@google.com>
Auto-Submit: Michael Pratt <mpratt@google.com>
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Change-Id: I7468b56eb26f14bc809f8f7580535e6562795c62
Reviewed-on: https://go-review.googlesource.com/c/go/+/723300 Reviewed-by: Michael Pratt <mpratt@google.com>
Auto-Submit: Michael Pratt <mpratt@google.com>
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thepudds [Thu, 20 Nov 2025 19:43:50 +0000 (14:43 -0500)]
io: reduce intermediate allocations in ReadAll and have a smaller final result
Currently, io.ReadAll allocates a significant amount of intermediate
memory as it grows its result slice to the size of the input data.
This CL aims to reduce the allocated memory. Geomean benchstat results
comparing existing io.ReadAll to this CL for a variety of input sizes:
│ old | new vs base │
sec/op 132.2µ 66.32µ -49.83%
B/op 645.4Ki 324.6Ki -49.70%
final-capacity 178.3k 151.3k -15.10%
excess-ratio 1.216 1.033 -15.10%
The corresponding full benchstat results are below. The input data sizes
are a blend of random sizes, power-of-2 sizes, and power-of-10 sizes.
This CL reduces intermediate bytes allocated in io.ReadAll by reading
via a set of slices of exponentially growing size, and then copying
into a final perfectly-sized slice at the end.
The current memory allocations impact real uses. For example, in #50774
two real-world reports were ~60% more bytes allocated via io.ReadAll
compared to an alternate approach, and also a separate report of
~5x more bytes allocated than the input data size of ~5MiB.
Separately, bytes.Buffer.ReadFrom uses a 2x growth strategy, which
usually can beat the pre-existing io.ReadAll on total bytes allocated
but sometimes not (depending on alignment between exact input data size
and growth). That said, bytes.Buffer.ReadFrom usually ends up with
more excess memory used in a larger final result than the current
io.ReadAll (often significantly more).
If we compare bytes.Buffer.ReadFrom to this CL, we also see
better geomean overall results reported with this CL:
(Full corresponding benchstat results comparing this CL vs. bytes.Buffer
are at https://go.dev/play/p/eqwk2BkaSwJ).
One challenge with almost any change of growth strategy for something
widely used is there can be a subset of users that benefited more from
the old growth approach (e.g., based on their data size aligning
particularly well with the old growth), even if the majority of users
on average benefit from the new growth approach.
To help mitigate that, this CL somewhat follows the old read pattern
in its early stages.
Here are the full benchstat results comparing the existing
io.ReadAll vs. this CL. The standard metrics are included, plus
the final result capacity and an excess capacity ratio, which is
the final capacity of the result divided by the input data size (so 1.0
is no excess memory present in the result, though due to
size class rounding the ratio is usually above 1.0 unless the
input data size exactly matches a size class).
We consider smaller reported excess capacity to be better for most
uses given it means the final allocation puts less pressure on the GC
(both in cases when it will almost immediately be garbage in user code,
or if for example the final result is held for multiple GC cycles).
The input data sizes used in the benchmarks:
- Six powers of 10.
- Six powers of 2.
- Ten random sizes between 1KiB and 100MiB (chosen uniformly
on a log scale).
- size=300 (so that we have something below 512, which is the
initial read size).
Finally, the read size in this CL currently grows exponentially
at a 1.5x growth rate. The old approach had its read size grow at
a ~1.25x growth rate once the reads are larger. We could consider
for example using a 1.25x read size growth rate here as well.
There are perhaps some ~mild trade-offs. One benefit might
be something like a ~5% smaller peak live heap contribution
(at the end, when copying into the final result) if we used
a 1.25x read growth instead of 1.5x read growth.
That said, for some systems, larger read sizes can trigger
higher throughput behavior further down the stack or
elsewhere in a system, such as via better read-ahead behavior,
larger transfer sizes, etc.
I've observed this effect in various real-world systems,
including distributed systems as well as for example with
spinning platters (which are still widely used, including
backing various "Internet scale" systems). When the effect
exists, it is usually substantial.
Therefore, my guess is it is better to get to larger read
sizes faster, which is one reason the CL is using 1.5x
read size growth rate instead of 1.25x. Also, for something
like peak live heap contribution, we are already getting
substantial wins in this CL for total heap bytes allocated,
so maybe that is OK.
(I have the actual benchmark in a separate commit, which I can
send later, or I can update this CL if preferred).
Fixes #50774
Updates #74299
Change-Id: I65eabf1d83a00fbdbe42e4c697116955f8251740
Reviewed-on: https://go-review.googlesource.com/c/go/+/722500
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com> Reviewed-by: Michael Pratt <mpratt@google.com> Reviewed-by: Keith Randall <khr@google.com> Reviewed-by: Keith Randall <khr@golang.org> Reviewed-by: Dmitri Shuralyov <dmitshur@google.com>
Dave Vasilevsky [Tue, 25 Nov 2025 03:55:45 +0000 (03:55 +0000)]
os: allow direntries to have zero inodes on Linux
Some Linux filesystems have been known to return valid enties with
zero inodes. This new behavior also puts Go in agreement with recent
glibc.
Fixes #76428
Change-Id: Ieaf50739a294915a3ea2ef8c5a3bb2a91a186881
GitHub-Last-Rev: 8f83d009ef0320fd3fe7cf03e55d5d24df57f015
GitHub-Pull-Request: golang/go#76448
Reviewed-on: https://go-review.googlesource.com/c/go/+/724220 Reviewed-by: Cherry Mui <cherryyz@google.com> Reviewed-by: Ian Lance Taylor <iant@golang.org>
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Ian Lance Taylor [Tue, 18 Nov 2025 04:20:26 +0000 (20:20 -0800)]
cmd/link: test that moduledata is in its own section
This is a test for CL 720660.
For #76038
Change-Id: I2f630b738ddb5a9c48e3c5d4374c1e995910541a
Reviewed-on: https://go-review.googlesource.com/c/go/+/721480 Reviewed-by: Cherry Mui <cherryyz@google.com>
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Auto-Submit: Ian Lance Taylor <iant@golang.org> Reviewed-by: David Chase <drchase@google.com>
Ian Lance Taylor [Tue, 18 Nov 2025 02:35:50 +0000 (18:35 -0800)]
cmd/link: test that findfunctab is in gopclntab section
This is a test for CL 719743.
Change-Id: I2d7b9d00d2d4dd63a21ca00f09eb7c9378ec70f8
Reviewed-on: https://go-review.googlesource.com/c/go/+/721461 Reviewed-by: David Chase <drchase@google.com>
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Auto-Submit: Ian Lance Taylor <iant@golang.org> Reviewed-by: Cherry Mui <cherryyz@google.com>
Ian Lance Taylor [Tue, 18 Nov 2025 02:29:42 +0000 (18:29 -0800)]
cmd/link: test that funcdata values are in gopclntab section
This is a test for CL 719440.
For #76038
Change-Id: I8fc55118b3c7dea39a36e04ffb060fcb6150af54
Reviewed-on: https://go-review.googlesource.com/c/go/+/721460 Reviewed-by: Cherry Mui <cherryyz@google.com> Reviewed-by: David Chase <drchase@google.com>
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Auto-Submit: Ian Lance Taylor <iant@golang.org>
Ian Lance Taylor [Thu, 13 Nov 2025 21:01:14 +0000 (13:01 -0800)]
cmd/link, runtime, debug/gosym: move pclntab magic to internal/abi
Change-Id: I2d3c41b0e61b994d7b04bd16a791fd226dc45269
Reviewed-on: https://go-review.googlesource.com/c/go/+/720302 Reviewed-by: Michael Knyszek <mknyszek@google.com> Reviewed-by: David Chase <drchase@google.com> Reviewed-by: Cherry Mui <cherryyz@google.com>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Since before Go 1 the Go linker has handled ELF by first building the
ELF section string table, and then pointing ELF section headers to it.
This duplicates code as sections are effectively created twice,
once with the name and then again with the full section header.
The code duplication also means that it's easy to create unnecessary
section names; for example, every internally linked Go program
currently contains the string ".go.fuzzcntrs" although most do not
have a section by that name.
This CL changes the linker to simply build the section string table
after all the sections are known.
Change-Id: I27ba15b2af3dc1b8d7436b6c409f818aa8e6bfb4
Reviewed-on: https://go-review.googlesource.com/c/go/+/718840 Reviewed-by: Cherry Mui <cherryyz@google.com> Reviewed-by: David Chase <drchase@google.com>
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thepudds [Tue, 25 Nov 2025 14:57:50 +0000 (09:57 -0500)]
cmd/compile: introduce alias analysis and automatically free non-aliased memory after growslice
This CL is part of a set of CLs that attempt to reduce how much work the
GC must do. See the design in https://go.dev/design/74299-runtime-freegc
This CL updates the compiler to examine append calls to prove
whether or not the slice is aliased.
If proven unaliased, the compiler automatically inserts a call to a new
runtime function introduced with this CL, runtime.growsliceNoAlias,
which frees the old backing memory immediately after slice growth is
complete and the old storage is logically dead.
Two append benchmarks below show promising results, executing up to
~2x faster and up to factor of ~3 memory reduction with this CL.
The approach works with multiple append calls for the same slice,
including inside loops, and the final slice memory can be escaping,
such as in a classic pattern of returning a slice from a function
after the slice is built. (The final slice memory is never freed with
this CL, though we have other work that tackles that.)
An example target for this CL is we automatically free the
intermediate memory for the appends in the loop in this function:
func f1(input []int) []int {
var s []int
for _, x := range input {
s = append(s, g(x)) // s cannot be aliased here
if h(x) {
s = append(s, x) // s cannot be aliased here
}
}
return s // slice escapes at end
}
In this case, the compiler and the runtime collaborate so that
the heap allocated backing memory for s is automatically freed after
a successful grow. (For the first grow, there is nothing to free,
but for the second and subsequent growths, the old heap memory is
freed automatically.)
The new runtime.growsliceNoAlias is primarily implemented
by calling runtime.freegc, which we introduced in CL 673695.
The high-level approach here is we step through the IR starting
from a slice declaration and look for any operations that either
alias the slice or might do so, and treat any IR construct we
don't specifically handle as a potential alias (and therefore
conservatively fall back to treating the slice as aliased when
encountering something not understood).
For loops, some additional care is required. We arrange the analysis
so that an alias in the body of a loop causes all the appends in that
same loop body to be marked aliased, even if the aliasing occurs after
the append in the IR:
func f2() {
var s []int
for i := range 10 {
s = append(s, i) // aliased due to next line
alias = s
}
}
For nested loops, we analyse the nesting appropriately so that
for example this append is still proven as non-aliased in the
inner loop even though it aliased for the outer loop:
func f3() {
for range 10 {
var s []int
for i := range 10 {
s = append(s, i) // append using non-aliased slice
}
alias = s
}
}
A good starting point is the beginning of the test/escape_alias.go file,
which starts with ~10 introductory examples with brief comments that
attempt to illustrate the high-level approach.
For more details, see the new .../internal/escape/alias.go file,
especially the (*aliasAnalysis).analyze method.
In the first benchmark, an append in a loop builds up a slice from
nothing, where the slice elements are each 64 bytes. In the table below,
'count' is the number of appends. With 1 append, there is no opportunity
for this CL to free memory. Once there are 2 appends, the growth from
1 element to 2 elements means the compiler-inserted growsliceNoAlias
frees the 1-element array, and we see a ~33% reduction in memory use
and a small reported speed improvement.
As the number of appends increases for example to 5, we are at
a ~20% speed improvement and ~45% memory reduction, and so on until
we reach ~40% faster and ~50% less memory allocated at the end of
the table.
There can be variation in the reported numbers based on -randlayout, so
this table is for 30 different values of -randlayout with a total
n=150. (Even so, there is still some variation, so we probably should
not read too much into small changes.) This is with GOAMD64=v3 on
a VM that gcc reports is cascadelake.
The second benchmark is similar, but instead uses an 8-byte integer
for the slice element. The first 4 appends in the loop never call into
the runtime thanks to the excellent CL 664299 introduced by Keith in
Go 1.25 that allows some <= 32 byte dynamically-sized slices to be on
the stack, so this CL is neutral for <= 32 bytes. Once the 5th append
occurs at count=5, a grow happens via the runtime and heap allocates
as normal, but freegc does not yet have anything to free, so we see
a small ~1.4ns penalty reported there. But once the second growth
happens, the older heap memory is now automatically freed by freegc,
so we start to see some benefit in memory reductions and speed
improvements, starting at a tiny speed improvement (close to a wash,
or maybe noise) by the second growth before count=10, and building up to
~2x faster with ~68% fewer allocated bytes reported.
Of course, these are just microbenchmarks, but likely indicate
there are some opportunities here.
The immediately following CL 712422 tackles inlining and is able to get
runtime.freegc working automatically with iterators such as used by
slices.Collect, which becomes able to automatically free the
intermediate memory from its repeated appends (which earlier
in this work required a temporary hand edit to the slices package).
For now, we only use the NoAlias version for element types without
pointers while waiting on additional runtime support in CL 698515.
Updates #74299
Change-Id: I1b9d286aa97c170dcc2e203ec0f8ca72d84e8221
Reviewed-on: https://go-review.googlesource.com/c/go/+/710015 Reviewed-by: Keith Randall <khr@google.com>
Auto-Submit: Keith Randall <khr@golang.org> Reviewed-by: Dmitri Shuralyov <dmitshur@google.com>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com> Reviewed-by: Keith Randall <khr@golang.org>
limeidan [Mon, 24 Nov 2025 09:28:42 +0000 (17:28 +0800)]
cmd/link, cmd/internal/obj: fix a remote call failure issue
When a function call exceeds the immediate value range of the instruction,
a trampoline is required to assist in the jump. Trampoline is only omitted
when plt is needed; otherwise, a check is required.
Change-Id: I7fe2e08d75f6f574475837b560e650bbd4215858
Reviewed-on: https://go-review.googlesource.com/c/go/+/724580 Reviewed-by: abner chenc <chenguoqi@loongson.cn>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com> Reviewed-by: sophie zhao <zhaoxiaolin@loongson.cn> Reviewed-by: Cherry Mui <cherryyz@google.com> Reviewed-by: Dmitri Shuralyov <dmitshur@google.com>
Mark Freeman [Mon, 24 Nov 2025 22:04:49 +0000 (17:04 -0500)]
go/types, types2: replace setDefType with pending type check
Given a type definition of the form:
type T RHS
The setDefType function would set T.fromRHS as soon as we knew its
top-level type. For instance, in:
type S struct { ... }
S.fromRHS is set to a struct type before type-checking anything inside
the struct.
This permit access to the (incomplete) RHS type in a cyclic type
declaration. Accessing this information is fraught (as it's incomplete),
but was used for reporting certain types of cycles.
This CL replaces setDefType with a check that ensures no value of type
T is used before its RHS is set up.
This CL is strictly more complete than what setDefType achieved. For
instance, it enables correct reporting for the below cycles:
type A [unsafe.Sizeof(A{})]int
var v any = 42
type B [v.(B)]int
func f() C {
return C{}
}
type C [unsafe.Sizeof(f())]int
Fixes #76383
Fixes #76384
Change-Id: I9dfab5b708013b418fa66e43362bb4d8483fedec
Reviewed-on: https://go-review.googlesource.com/c/go/+/724140
Auto-Submit: Mark Freeman <markfreeman@google.com> Reviewed-by: Robert Griesemer <gri@google.com>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
crypto,testing/cryptotest: ignore random io.Reader params, add SetGlobalRandom
First, we centralize all random bytes generation through drbg.Read. The
rest of the FIPS 140-3 module can't use external functions anyway, so
drbg.Read needs to have all the logic.
Then, make sure that the crypto/... tree uses drbg.Read (or the new
crypto/internal/rand.Reader wrapper) instead of crypto/rand, so it is
unaffected by applications setting crypto/rand.Reader.
Next, pass all unspecified random io.Reader parameters through the new
crypto/internal/rand.CustomReader, which just redirects to drbg.Read
unless GODEBUG=cryptocustomrand=1 is set. Move all the calls to
MaybeReadByte there, since it's only needed for these custom Readers.
Finally, add testing/cryptotest.SetGlobalRandom which sets
crypto/rand.Reader to a locked deterministic source and overrides
drbg.Read. This way SetGlobalRandom should affect all cryptographic
randomness in the standard library.
Fixes #70942
Co-authored-by: qiulaidongfeng <2645477756@qq.com>
Change-Id: I6a6a69641311d9fac318abcc6d79677f0e406100
Reviewed-on: https://go-review.googlesource.com/c/go/+/724480 Reviewed-by: Nicholas Husin <nsh@golang.org>
Auto-Submit: Filippo Valsorda <filippo@golang.org> Reviewed-by: Nicholas Husin <husin@google.com> Reviewed-by: Roland Shoemaker <roland@golang.org>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
matloob [Wed, 26 Nov 2025 23:04:22 +0000 (18:04 -0500)]
runtime: update mkmalloc to make generated code look nicer
This cl adds a new operation that can remove an if statement or replace
it with its body if its condition is var or !var for some variable var
that's being replaced with a constant.
Change-Id: I864abf1f023b2a66b2299ca65d4f837d6a6a6964
Reviewed-on: https://go-review.googlesource.com/c/go/+/724940
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com> Reviewed-by: Michael Knyszek <mknyszek@google.com> Reviewed-by: Michael Matloob <matloob@google.com>
Auto-Submit: Michael Matloob <matloob@google.com>
Daniel Morsing [Thu, 25 Sep 2025 16:26:03 +0000 (17:26 +0100)]
runtime/secret: implement new secret package
Implement secret.Do.
- When secret.Do returns:
- Clear stack that is used by the argument function.
- Clear all the registers that might contain secrets.
- On stack growth in secret mode, clear the old stack.
- When objects are allocated in secret mode, mark them and then zero
the marked objects immediately when they are freed.
- If the argument function panics, raise that panic as if it originated
from secret.Do. This removes anything about the secret function
from tracebacks.
For now, this is only implemented on linux for arm64 and amd64.
This is a rebased version of Keith Randalls initial implementation at
CL 600635. I have added arm64 support, signal handling, preemption
handling and dealt with vDSOs spilling into system stacks.
Fixes #21865
Change-Id: I6fbd5a233beeaceb160785e0c0199a5c94d8e520 Co-authored-by: Keith Randall <khr@golang.org>
Reviewed-on: https://go-review.googlesource.com/c/go/+/704615 Reviewed-by: Roland Shoemaker <roland@golang.org>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Auto-Submit: Filippo Valsorda <filippo@golang.org> Reviewed-by: Cherry Mui <cherryyz@google.com>
Alan Donovan [Mon, 21 Jul 2025 18:35:08 +0000 (14:35 -0400)]
go/types: relax NewSignatureType for append(slice, str...)
CL 688815 contained a partial fix for the reported bug, but
NewSignatureType continued to panic. This change relaxes it
to permit construction of the type "func([]byte, B) []byte"
where "type B []byte". We must do so because a client
may instantiate the type "func([]byte, T...)" where [T ~string|~[]byte]
at T=B, and may have no way to know that they are dealing
with this very special edge case of append.
Added a regression test of NewSignatureType, which I should
have done in the earlier CL.
Also, make typestring less pedantic and fragile.
Fixes #73871
Change-Id: I3d8f8609582149f9c9f8402a04ad516c2c63bbc6
Reviewed-on: https://go-review.googlesource.com/c/go/+/689277
TryBot-Bypass: Alan Donovan <adonovan@google.com> Reviewed-by: Robert Findley <rfindley@google.com>
Auto-Submit: Alan Donovan <adonovan@google.com> Reviewed-by: Mark Freeman <markfreeman@google.com>
matloob [Wed, 26 Nov 2025 15:30:34 +0000 (10:30 -0500)]
cmd/go: remove experiment checks for compile -c
There's a comment that we should test that compile -c is compatible with
the fieldtrack and preemptibleloops experiments and then remove the
check disabling -c when those experiments are enabled.
I tested this and the tests pass with fieldtrack (with the exception of one go command test that makes the assumption that fieldtrack is off), and the preemptibleloops experiment is already broken without this experiment.
Also remove the check for the value of the GO19CONCURRENTCOMPILATION
environment variable. The compiler concurrency can be limited by setting
GOMAXPROCS.
Change-Id: I0c02745de463ea572673648061185cd76a6a6964
Reviewed-on: https://go-review.googlesource.com/c/go/+/724680 Reviewed-by: Alan Donovan <adonovan@google.com> Reviewed-by: Cherry Mui <cherryyz@google.com>
Auto-Submit: Michael Matloob <matloob@golang.org>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Dmitri Shuralyov [Wed, 26 Nov 2025 21:12:53 +0000 (16:12 -0500)]
doc/next: document broken freebsd/riscv64 port
Also update comment in cmd/dist's broken map to point to the top-level
umbrella issue.
For #76475.
For #75005.
Change-Id: I43b8384af4264dc5d72ceea8d05730b9db81123a
Reviewed-on: https://go-review.googlesource.com/c/go/+/724860 Reviewed-by: Cherry Mui <cherryyz@google.com> Reviewed-by: Dmitri Shuralyov <dmitshur@google.com>
Auto-Submit: Dmitri Shuralyov <dmitshur@golang.org>
TryBot-Bypass: Dmitri Shuralyov <dmitshur@golang.org>
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