delta/go-git.git/misc, branch dev.unified

all: disable tests that fail on Alpine

2022-08-02T17:23:42+00:00

These changes are enough to pass all.bash using the
disabled linux-amd64-alpine builder via debugnewvm.

For #19938.
For #39857.

Change-Id: I7d160612259c77764b70d429ad94f0864689cdce
Reviewed-on: https://go-review.googlesource.com/c/go/+/419995
TryBot-Result: Gopher Robot 
Run-TryBot: Russ Cox 
Reviewed-by: Ian Lance Taylor

misc/cgo/test: use fewer threads in TestSetgidStress in long mode

2022-07-27T20:21:13+00:00

TestSetgidStress originally spawns 1000 threads for stress testing.
It caused timeout on some builders so CL 415677 reduced to 50 in
short mode. But it still causes flaky timeouts in longtest
builders, so reduce the number of threads in long mode as well.

Should fix #53641.

Change-Id: I02f4ef8a143bb1faafe3d11ad223f36f5cc245c6
Reviewed-on: https://go-review.googlesource.com/c/go/+/419453
Reviewed-by: Bryan Mills 
Run-TryBot: Cherry Mui 
TryBot-Result: Gopher Robot

cmd/compile: make jump table symbol local

2022-07-22T20:12:19+00:00

When using plugins, if the plugin and the main executable both
have the same function, and if it uses jump table, currently the
jump table symbol have the same name so it will be deduplicated by
the dynamic linker. This causes a function in the plugin may (in
the middle of the function) jump to the function with the same name
in the main executable (or vice versa). But the function may be
compiled slightly differently, because the plugin needs to be PIC.
Jumping from the middle of one function to the other will not work.
Avoid this problem by marking the jump table symbol local to a DSO.

Fixes #53989.

Change-Id: I2b573b9dfc22401c8a09ffe9b9ea8bb83d3700ca
Reviewed-on: https://go-review.googlesource.com/c/go/+/418960
Reviewed-by: Keith Randall 
Run-TryBot: Cherry Mui 
Reviewed-by: Than McIntosh 
TryBot-Result: Gopher Robot

misc/cgo/testshared: run tests only in GOPATH mode

2022-07-13T20:43:22+00:00

-buildmode=shared installs shared libraries into GOROOT
and expects to reuse them across builds.
Builds in module mode, however, each have their own set of
dependencies (determined by the module's requirements), so in general
cannot share dependencies with a single GOROOT.

Ideally in the long term we would like to eliminate -buildmode=shared
entirely (see #47788), but first we need a replacement for the subset
of use-cases where it still works today.

In the meantime, we should run these tests only in GOPATH mode.
Non-main packages in module mode should not be installed to
GOPATH/pkg, but due to #37015 they were installed there anyway,
and this test heavily relies on installing non-main packages.

For #37015.

Change-Id: I7c5d90b4075d6f33e3505d6a8f12752309ae5c03
Reviewed-on: https://go-review.googlesource.com/c/go/+/417194
Run-TryBot: Bryan Mills 
Reviewed-by: Ian Lance Taylor 
TryBot-Result: Gopher Robot 
Auto-Submit: Bryan Mills

misc/cgo/testcshared: don't rely on an erroneous install target in tests

2022-07-13T20:43:20+00:00

Non-main packages in module mode should not be installed to
GOPATH/pkg, but due to #37015 they were installed there anyway.

This change switches the 'go install' command in createHeaders to
instead use 'go build' (with an extension determined by the install
target for 'runtime/cgo', which is well-defined at least for the
moment), and switches TestCachedInstall (which appears to be
explicitly testing 'go install') to explicitly request GOPATH mode
(which provides a well-defined install target for the library).

This change follows a similar structure to CL 416954.

For #37015.

Change-Id: I22ae4af0f0d4c50adc9e0f0dc279859d1f258cc8
Reviewed-on: https://go-review.googlesource.com/c/go/+/417096
Run-TryBot: Bryan Mills 
TryBot-Result: Gopher Robot 
Auto-Submit: Bryan Mills 
Reviewed-by: Ian Lance Taylor

misc/cgo/testcarchive: don't rely on an erroneous install target in tests

2022-07-11T18:57:03+00:00

Non-main packages in module mode should not be installed to
GOPATH/pkg, but due to #37015 they were installed there anyway.

This change switches the 'go install' command in TestPIE to instead
use 'go build', and switches TestInstall and TestCachedInstall
(which appear to be explicitly testing 'go install') to explicitly
request GOPATH mode (which does have a well-defined install target).

For #37015.

Change-Id: Ifb24657d2781d1e35cf40078e8e3ebf56aab9cc8
Reviewed-on: https://go-review.googlesource.com/c/go/+/416954
TryBot-Result: Gopher Robot 
Run-TryBot: Bryan Mills 
Auto-Submit: Bryan Mills 
Reviewed-by: Ian Lance Taylor

misc/cgo/test: make TestSetgidStress cheaper

2022-07-06T14:23:50+00:00

TestSetgidStress spawns 1000 threads, which can be expensive on
some platforms or slow builders. Run with 50 threads in short
mode instead.

This makes the failure less reproducible even with buggy code. But
one can manually stress test it (e.g. when a flaky failure appear
on the builder).

Fixes #53641.

Change-Id: I33b5ea5ecaa8c7a56f59c16f9171657ee295db47
Reviewed-on: https://go-review.googlesource.com/c/go/+/415677
Reviewed-by: Austin Clements 
TryBot-Result: Gopher Robot 
Run-TryBot: Cherry Mui

cmd/internal/obj/arm64: save LR and SP in one instruction for small frames

2022-06-29T22:26:58+00:00

When we create a thread with signals blocked. But glibc's
pthread_sigmask doesn't really allow us to block SIGSETXID. So we
may get a signal early on before the signal stack is set. If we
get a signal on the current stack, it will clobber anything below
the SP. This CL makes it to save LR and decrement SP in a single
MOVD.W instruction for small frames, so we don't write below the
SP.

We used to use a single MOVD.W instruction before CL 379075.
CL 379075 changed to use an STP instruction to save the LR and FP,
then decrementing the SP. This CL changes it back, just this part
(epilogues and large frame prologues are unchanged). For small
frames, it is the same number of instructions either way.

This decreases the size of a "small" frame from 0x1f0 to 0xf0.
For frame sizes in between, it could benefit from using an
STP instruction instead of using the prologue for the "large"
frame case. We don't bother it for now as this is a stop-gap
solution anyway.

This only addresses the issue with small frames. Luckily, all
functions from thread entry to setting up the signal stack have
samll frames.

Other possible ideas:
- Expand the unwind info metadata, separate SP delta and the
  location of the return address, so we can express "SP is
  decremented but the return address is in the LR register". Then
  we can always create the frame first then write the LR, without
  writing anything below the SP (except the frame pointer at SP-8,
  which is minor because it doesn't really affect program
  execution).
- Set up the signal stack immediately in mstart in assembly.

For Go 1.19 we do this simple fix. We plan to do the metadata fix
in Go 1.20 ( #53609 ).

Other LR architectures are addressed in CL 413428.

Fix #53374.

Change-Id: I9d6582ab14ccb06ac61ad43852943d9555e22ae5
Reviewed-on: https://go-review.googlesource.com/c/go/+/412474
Run-TryBot: Cherry Mui 
TryBot-Result: Gopher Robot 
Reviewed-by: Austin Clements 
Reviewed-by: Eric Fang

cmd/go: prepend builtin prolog when checking for preamble errors

2022-06-25T19:07:01+00:00

Fixes #50710

Change-Id: I62feddbe3eaae9605d196bec60d378614436603a
Reviewed-on: https://go-review.googlesource.com/c/go/+/379754
Auto-Submit: Ian Lance Taylor 
Reviewed-by: Dmitri Shuralyov 
TryBot-Result: Gopher Robot 
Run-TryBot: Ian Lance Taylor 
Reviewed-by: Ian Lance Taylor 
Reviewed-by: Dmitri Shuralyov

cmd/cgo: dont override declared struct type

2022-06-22T16:21:49+00:00

Fixes #52611

Change-Id: I835df8d6a98a37482446ec00af768c96fd8ee4fe
GitHub-Last-Rev: ea54dd69eef90eaf1641889039344fff70158ece
GitHub-Pull-Request: golang/go#52733
Reviewed-on: https://go-review.googlesource.com/c/go/+/404497
Run-TryBot: Ian Lance Taylor 
Reviewed-by: Ian Lance Taylor 
Reviewed-by: Dexter Ouyang 
Auto-Submit: Ian Lance Taylor 
Run-TryBot: Ian Lance Taylor 
Reviewed-by: Alex Rakoczy 
TryBot-Result: Gopher Robot