cmd/dist, cmd/go: enable more warnings, make clang errors legible
This does not change the default compiler on OS X to clang.
It appears that for now we can keep using gcc as long as we
enable a few more warning settings that are on-by-default
elsewhere.
R=golang-dev, bradfitz, dave
CC=golang-dev
https://golang.org/cl/11610044
runtime: use funcdata to supply garbage collection information
This CL introduces a FUNCDATA number for runtime-specific
garbage collection metadata, changes the C and Go compilers
to emit that metadata, and changes the runtime to expect it.
The old pseudo-instructions that carried this information
are gone, as is the linker code to process them.
Keith Randall [Fri, 19 Jul 2013 18:19:18 +0000 (11:19 -0700)]
runtime: cleanup: use ArgsSizeUnknown to mark all functions
whose argument size is unknown (C vararg functions, and
assembly code without an explicit specification).
We used to use 0 to mean "unknown" and 1 to mean "zero".
Now we use ArgsSizeUnknown (0x80000000) to mean "unknown".
runtime: prevent sysmon from polling network excessivly
If the network is not polled for 10ms, sysmon starts polling network
on every iteration (every 20us) until another thread blocks in netpoll.
Fixes #5922.
David Symonds [Fri, 19 Jul 2013 13:44:22 +0000 (23:44 +1000)]
regexp: exclude exhaustive RE2 test from running under race detector.
It is an expensive test to run, and even more so with -race,
and causes timeouts on builders. It is doubtful that it would
find a race that other tests in this package wouldn't, so there
is little loss in excluding it.
Update #5837.
R=golang-dev, dave
CC=golang-dev
https://golang.org/cl/11568043
runtime: handle morestack/lessstack in stack trace
If we start a garbage collection on g0 during a
stack split or unsplit, we'll see morestack or lessstack
at the top of the stack. Record an argument frame size
for those, and record that they terminate the stack.
Deferreturn is synthesizing a new call frame.
It must not be interrupted between copying the args there
and fixing up the program counter, or else the stack will
be in an inconsistent state, one that will confuse the
garbage collector.
With preemption, _sfloat2 can show up in stack traces.
Write the function prototype in a way that accurately
shows the frame size and the fact that it might contain
pointers.
runtime: mark concatstring as variadic (fixes 386 build)
Windows was the only one seeing this bug reliably in the builder,
but it was easy to reproduce using 'GOGC=1 go test strconv'.
concatstring looked like it took only one string, but in fact it
takes a long list of strings. Add an explicit ... so that the traceback
will not use the "fixed" frame size and instead look at the
frame size metadata recorded by the caller.
This will behave like similar "*-other-window" functions in Emacs.
Default key bind is C-x 4 C-c C-j – while awkward, it follows both
the convention for other-window functions and the convention for
not using user- or emacs-reserved keys.
I believe the runtime is strong enough now to reenable
preemption during the function prologue.
Assuming this is or can be made stable, it will be in Go 1.2.
More aggressive preemption is not planned for Go 1.2.
runtime: more reliable preemption
Currently preemption signal g->stackguard0==StackPreempt
can be lost if it is received when preemption is disabled
(e.g. m->lock!=0). This change duplicates the preemption
signal in g->preempt and restores g->stackguard0
when preemption is enabled.
Update #543.
With this CL, I believe the runtime always knows
the frame size during the gc walk. There is no fallback
to "assume entire stack frame of caller" anymore.
Joel Sing [Wed, 17 Jul 2013 16:33:16 +0000 (12:33 -0400)]
crypto/tls: Add support for ECDHE-ECDSA
Add support for ECDHE-ECDSA (RFC4492), which uses an ephemeral server
key pair to perform ECDH with ECDSA signatures. Like ECDHE-RSA,
ECDHE-ECDSA also provides PFS.
Daniel Morsing [Wed, 17 Jul 2013 09:04:34 +0000 (11:04 +0200)]
cmd/8g: Make clearfat non-interleaved with pointer calculations.
clearfat (used to zero initialize structures) will use AX for x86 block ops. If we write to AX while calculating the dest pointer, we will fill the structure with incorrect values.
Since 64-bit arithmetic uses AX to synthesize a 64-bit register, getting an adress by indexing with 64-bit ops can clobber the register.
runtime: record argument size in assembly functions
I have not done the system call stubs in sys_*.s.
I hope to avoid that, because those do not block, so those
frames will not appear in stack traces during garbage
collection.
syscall: record argument size for all assembly functions
While we're here, fix Syscall9 on NetBSD and OpenBSD:
it was storing the results into the wrong memory locations.
I guess no one uses that function's results on those systems.
Part of cleaning up stack traces and argument frame information.
cmd/gc: do not race instrument syscall.forkAndExecInChild
Race instrumentation can allocate, switch stacks, preempt, etc.
All that is not allowed in between fork and exec.
Fixes #4840.
R=golang-dev, daniel.morsing, dave
CC=golang-dev
https://golang.org/cl/11324044
cmd/gc: fix race detector instrumentation of type switches.
A type switch on a value with map index expressions,
could get a spurious instrumentation from a OTYPESW node.
These nodes do not need instrumentation because after
walk the type switch has been turned into a sequence
of ifs.
"M requires pointer receiver" can be misinterpreted to
mean that method M should have a pointer receiver but
does not. In fact the message means "M has a pointer
receiver" (and you don't have a pointer).
The postinstall script causes the installation to fail because the last
step that copies files for Xcode is broken. Two details can cause the
command to fail:
1. The XCODE_MISC_DIR value has a space. Without quotes in the cp
command, cp will just complain that this is an invalid syntax.
2. The source of the cp is a directory with two subdirectories.
We actually want the files for either Xcode 3 or Xcode 4 to be copied.
Using xcodebuild -version, we check for the Xcode version and
select which of xcode/3/* or xcode/4/* should be the source
of the copy.
cmd/go, testing: streamline direct use of test binaries
Before:
$ go test -c -cover fmt
$ ./fmt.test -test.covermode=set
PASS
coverage: 65.1% of statements in strconv
$
After:
$ go test -c -cover fmt
$ ./fmt.test
PASS
coverage: 65.1% of statements in strconv
$
In addition to being cumbersome, the old flag didn't make sense:
the cover mode cannot be changed after the binary has been built.
Another useful effect of this CL is that if you happen to do
$ go test -c -covermode=atomic fmt
and then forget you did that and run benchmarks,
the final line of the output (the coverage summary) reminds you
that you are benchmarking with coverage enabled, which might
not be what you want.
We put this in because Marshal encoded named []byte but Unmarshal rejected them.
And we noticed that Marshal's behavior was undocumented so we documented it.
But I am starting to think the docs and Unmarshal were correct and Marshal's
behavior was the problem.
Rolling back to give us more time to think.
««« original CL description
json: unmarshal types that are byte slices.
The json package cheerfully would marshal
type S struct {
IP net.IP
}
but would give an error when unmarshalling. This change allows any
type whose concrete type is a byte slice to be unmarshalled from a
string.
encoding/json: coerce invalid UTF-8 to valid UTF-8 during Marshal
In practice, rejecting an entire structure due to a single invalid byte
in a string is just too picky, and too hard to track down.
Be consistent with the bulk of the standard library by converting
invalid UTF-8 into UTF-8 with replacement runes.
Shenghou Ma [Fri, 12 Jul 2013 18:00:07 +0000 (02:00 +0800)]
run.bash: enlarge timeout of runtime tests
Recently addition to runtime test makes it take very close to 720s
of timeout limit on the netbsd-arm-qemu builder.
cmd/5g, cmd/6g, cmd/8g: fix line number of caller of deferred func
Deferred functions are not run by a call instruction. They are run by
the runtime editing registers to make the call start with a caller PC
returning to a
CALL deferreturn
instruction.
That instruction has always had the line number of the function's
closing brace, but that instruction's line number is irrelevant.
Stack traces show the line number of the instruction before the
return PC, because normally that's what started the call. Not so here.
The instruction before the CALL deferreturn could be almost anywhere
in the function; it's unrelated and its line number is incorrect to show.
Fix the line number by inserting a true hardware no-op with the right
line number before the returned-to CALL instruction. That is, the deferred
calls now appear to start with a caller PC returning to the second instruction
in this sequence:
NOP
CALL deferreturn
The traceback will show the line number of the NOP, which we've set
to be the line number of the function's closing brace.
The NOP here is not the usual pseudo-instruction, which would be
elided by the linker. Instead it is the real hardware instruction:
XCHG AX, AX on 386 and amd64, and AND.EQ R0, R0, R0 on ARM.
Fixes #5856.
R=ken2, ken
CC=golang-dev
https://golang.org/cl/11223043
If the stack frame size is larger than the known-unmapped region at the
bottom of the address space, then the stack split prologue cannot use the usual
condition:
SP - size >= stackguard
because SP - size may wrap around to a very large number.
Instead, if the stack frame is large, the prologue tests:
SP - stackguard >= size
(This ends up being a few instructions more expensive, so we don't do it always.)
Preemption requests register by setting stackguard to a very large value, so
that the first test (SP - size >= stackguard) cannot possibly succeed.
Unfortunately, that same very large value causes a wraparound in the
second test (SP - stackguard >= size), making it succeed incorrectly.
To avoid *that* wraparound, we have to amend the test:
cmd/go, testing: remove redundant "for pkg" in coverage message
This is a transcript before this change. I've capitalized the text being removed.
Note that it is always near another line that already says fmt, marked with <<<
$ cd $GOROOT/src/pkg/fmt
$ go test -cover
PASS
coverage FOR FMT: 91.3% of statements
ok fmt 0.040s <<<
$ go test -coverpkg strconv
PASS
coverage FOR FMT: 64.9% of statements in strconv
ok fmt 0.039s <<<
$ go test -cover -c
$ ./fmt.test -test.covermode=set <<<
PASS
coverage FOR FMT: 91.3% of statements
$ go test -coverpkg strconv -c
$ ./fmt.test -test.covermode=set <<<
PASS
coverage FOR FMT: 64.9% of statements in strconv
That the summary printed by 'go test [options] fmt' is unchanged:
$ go test -cover fmt
ok fmt 0.040s coverage: 91.3% of statements
$ go test -coverpkg strconv fmt
ok fmt 0.038s coverage: 64.9% of statements in strconv
The current cas64 definition hard-codes the x86 behavior
of updating *old with the new value when the cas fails.
This is inconsistent with cas32 and casp.
Make it consistent.
This means that the cas64 uses will be epsilon less efficient
than they might be, because they have to do an unnecessary
memory load on x86. But so be it. Code clarity and consistency
is more important.
misc/cgo/test: make test work with -linkmode=internal
The static func named thread in issue5337.go's C snippet
conflicts with the static func named thread in issue3350.go's C snippet.
I don't know why (they're both static) but I also don't care,
because -linkmode=internal only needs to be able to handle
the cgo in the standard library, and it does.
Change the test to avoid this problem.
Fixes build (after run.bash is fixed to detect the breakage).
STRINGSZ (200) is fine for lines generated by things like
instruction dumps, but an error containing a couple file
names can easily exceed that, especially on Macs with
the ridiculous default $TMPDIR.