delta/go-git.git/src/runtime, branch dev.inline

runtime/cgo: retry pthread_create on EAGAIN for OpenBSD

2016-12-05T21:15:05+00:00

For reasons that I do not know, OpenBSD does not call pthread_create
directly, but instead looks it up in libpthread.so. That means that we
can't use the code used on other systems to retry pthread_create on
EAGAIN, since that code simply calls pthread_create.

This patch copies that code to an OpenBSD-specific version.

Also, check for an EAGAIN failure in the test, as that seems to be the
underlying cause of the test failure on several systems including OpenBSD.

Fixes #18146.

Change-Id: I3bceaa1e03a7eaebc2da19c9cc146b25b59243ef
Reviewed-on: https://go-review.googlesource.com/33905
Run-TryBot: Ian Lance Taylor 
TryBot-Result: Gobot Gobot 
Reviewed-by: Brad Fitzpatrick

runtime/cgo: retry pthread_create on EAGAIN

2016-12-05T18:46:18+00:00

Update #18146.

Change-Id: Ib447aabae9f203a8b61fb8c984b57d8e2bfe69c2
Reviewed-on: https://go-review.googlesource.com/33894
Run-TryBot: Ian Lance Taylor 
TryBot-Result: Gobot Gobot 
Reviewed-by: Brad Fitzpatrick

runtime: don't skip TestCgoCallbackGC on FreeBSD

2016-12-05T18:10:50+00:00

Seems to be fixed according to discussion on issue 16396.

Fixes #16396.

Change-Id: Ibac7037a24280204e48cb4d3000af524f65afd36
Reviewed-on: https://go-review.googlesource.com/33903
Run-TryBot: Ian Lance Taylor 
TryBot-Result: Gobot Gobot 
Reviewed-by: Brad Fitzpatrick

runtime: check that Version does not contain \r \n

2016-12-05T16:49:53+00:00

Change-Id: I8982cfa7337ec457b5235a207ebfda00ef6a2e5a
Reviewed-on: https://go-review.googlesource.com/33917
Run-TryBot: Russ Cox 
TryBot-Result: Gobot Gobot 
Reviewed-by: Brad Fitzpatrick

runtime: skip GDB tests on mips64

2016-12-03T17:25:26+00:00

Updates #18173

Change-Id: I4c667c89ba3bf16433a4cef7cb01054f1798667d
Reviewed-on: https://go-review.googlesource.com/33892
Run-TryBot: Brad Fitzpatrick 
TryBot-Result: Gobot Gobot 
Reviewed-by: Ian Lance Taylor

runtime: fix incorrect comment about bitvector layout

2016-12-01T16:42:47+00:00

Commit 303b69fe packed bitvectors more tightly, but missed a comment
describing their old layout. Update that comment.

Change-Id: I095ccb01f245197054252545f37b40605a550dec
Reviewed-on: https://go-review.googlesource.com/33718
Reviewed-by: Matthew Dempsky

Revert "runtime: handle SIGPIPE in c-archive and c-shared programs"

2016-12-01T11:23:17+00:00

This reverts commit d24b57a6a1a3530e590b7c0a72dc78043e198630.

Reason for revert: Further complications arised (issue 18100). We'll try again in Go 1.9.

Change-Id: I5ca93d2643a4be877dd9c2d8df3359718440f02f
Reviewed-on: https://go-review.googlesource.com/33770
TryBot-Result: Gobot Gobot 
Reviewed-by: Minux Ma 
Run-TryBot: Minux Ma

runtime: fix undead arguments in cgocall

2016-11-30T17:09:17+00:00

From the garbage collector's perspective, time can move backwards in
cgocall. However, in the midst of this time warp, the pointer
arguments to cgocall can go from dead back to live. If a stack growth
happens while they're dead and then a GC happens when they become live
again, GC can crash with a bad heap pointer.

Specifically, the sequence that leads to a panic is:

1. cgocall calls entersyscall, which saves the PC and SP of its call
site in cgocall. Call this PC/SP "X". At "X" both pointer arguments
are live.

2. cgocall calls asmcgocall. Call the PC/SP of this call "Y". At "Y"
neither pointer argument is live.

3. asmcgocall calls the C code, which eventually calls back into the
Go code.

4. cgocallbackg remembers the saved PC/SP "X" in some local variables,
calls exitsyscall, and then calls cgocallbackg1.

5. The Go code causes a stack growth. This stack unwind sees PC/SP "Y"
in the cgocall frame. Since the arguments are dead at "Y", they are
not adjusted.

6. The Go code returns to cgocallbackg1, which calls reentersyscall
with the recorded saved PC/SP "X", so "X" gets stashed back into
gp.syscallpc/sp.

7. GC scans the stack. It sees there's a saved syscall PC/SP, so it
starts the traceback at PC/SP "X". At "X" the arguments are considered
live, so it scans them, but since they weren't adjusted, the pointers
are bad, so it panics.

This issue started as of commit ca4089ad, when the compiler stopped
marking arguments as live for the whole function.

Since this is a variable liveness issue, fix it by adding KeepAlive
calls that keep the arguments live across this whole time warp.

The existing issue7978 test has all of the infrastructure for testing
this except that it's currently up to chance whether a stack growth
happens in the callback (it currently only happens on the
linux-amd64-noopt builder, for example). Update this test to force a
stack growth, which causes it to fail reliably without this fix.

Fixes #17785.

Change-Id: If706963819ee7814e6705693247bcb97a6f7adb8
Reviewed-on: https://go-review.googlesource.com/33710
Reviewed-by: Brad Fitzpatrick 
Reviewed-by: Keith Randall

runtime: use standard comment style in cgocall

2016-11-30T17:09:06+00:00

Change-Id: I9f2c2da4aa512729ae40562b06601da95ba50d6f
Reviewed-on: https://go-review.googlesource.com/33689
Reviewed-by: Brad Fitzpatrick 
Reviewed-by: Keith Randall

runtime: fall back to /proc/self/auxv in Android libs

2016-11-29T15:27:53+00:00

Android's libc doesn't provide access to auxv, so currently the Go
runtime synthesizes a fake, minimal auxv when loaded as a library on
Android. This used to be sufficient, but now we depend on auxv to
retrieve the system physical page size and panic if we can't retrieve
it.

Fix this by falling back to reading auxv from /proc/self/auxv if the
loader-provided auxv is empty and removing the synthetic auxv vectors.

Fixes #18041.

Change-Id: Ia2ec2c764a6609331494a5d359032c56cbb83482
Reviewed-on: https://go-review.googlesource.com/33652
Run-TryBot: Austin Clements 
TryBot-Result: Gobot Gobot 
Reviewed-by: David Crawshaw