This eliminates ~75% of the nil checks being emitted,
on all architectures. We can do better, but we need
a bit more general support from the compiler, and
I don't want to do that so close to Go 1.2.
What's here is simple but effective and safe.
A few small code generation cleanups were required
to make the analysis consistent on all systems about
which nil checks are omitted, at least in the test.
Adam Langley [Tue, 17 Sep 2013 17:30:36 +0000 (13:30 -0400)]
crypto/tls: don't select ECDSA ciphersuites with only an RSA certificate.
47ec7a68b1a2 added support for ECDSA ciphersuites but didn't alter the
cipher suite selection to take that into account. Thus Go servers could
try and select an ECDSA cipher suite while only having an RSA
certificate, leading to connection failures.
text/template/parse, html/template: copy Tree.text during html template clone
The root cause of the panic reported in https://code.google.com/p/go/issues/detail?id=5980
is that parse's Tree.Text wasn't being copied during the clone.
Fix this by adding and using a Copy method for parse.Tree.
Fixes #5980.
R=golang-dev, r
CC=golang-dev
https://golang.org/cl/12420044
Carl Shapiro [Tue, 17 Sep 2013 02:03:19 +0000 (19:03 -0700)]
runtime: export PCDATA value reader
This interface is required to use the PCDATA interface
implemented in Go 1.2. While initially entirely private, the
FUNCDATA side of the interface has been made public. This
change completes the FUNCDATA/PCDATA interface.
Hide container symbols like text and etext so that
the individual pieces inside are shown instead.
For example, if text and main.init have the same
address, it was a toss-up which name was printed.
The code for call site-specific pointer bitmaps was not ready in time,
but the zeroing required without it is too expensive to use by default.
We will have to wait for precise collection of stack frames until Go 1.3.
The precise collection can be re-enabled by
GOEXPERIMENT=precisestack ./all.bash
but that will not be the default for a Go 1.2 build.
Fixes #6087.
R=golang-dev, jeremyjackins, dan.kortschak, r
CC=golang-dev
https://golang.org/cl/13677045
The uint64 divide function calls _mul64x32 to do a 64x32-bit multiply
and then compares the result against the 64-bit numerator.
If the result is bigger than the numerator, must use the slow path.
Unfortunately, the 64x32 produces a 96-bit product, and only the
low 64 bits were being used in the comparison. Return all 96 bits,
the bottom 64 via the original uint64* pointer, and the top 32
as the function's return value.
runtime, syscall: work around FreeBSD/amd64 kernel bug
The kernel implementation of the fast system call path,
the one invoked by the SYSCALL instruction, is broken for
restarting system calls. A C program demonstrating this is below.
Change the system calls to use INT $0x80 instead, because
that (perhaps slightly slower) system call path actually works.
I filed http://www.freebsd.org/cgi/query-pr.cgi?pr=182161.
The C program demonstrating that it is FreeBSD's fault is below.
It reports the same "Bad address" failures from wait.
Andrew Gerrand [Mon, 16 Sep 2013 05:47:13 +0000 (15:47 +1000)]
doc: re-organize golang.org site content
Remove "References" section.
Remove most articles and redirect to blog.golang.org.
Move /ref/spec and /ref/mem to /doc/spec and /doc/mem.
Remove duplicate links from the remaining
"Documents", "The Project", and "Help" pages.
Defer to the wiki for more links and community content.
Update command reference and mention cover tool.
Add "Pop-out" text to the front page.
Pick one of four videos at random to feature on the front page.
Rob Pike [Mon, 16 Sep 2013 00:26:23 +0000 (10:26 +1000)]
encoding/gob: ignore chan and func fields of structures
Previously, fields of type chan or func caused an error.
Now we just treat them like unexported fields and ignore them.
This makes it easier to guarantee long-term compatibilty since
a substructure from another package cannot break gob
encoding by adding a func or chan field.
cmd/gc: don't generate algs for internal map types.
Fake types describing the internal structure of hashmaps are
generated for use by precise GC.
Generating hash and eq functions for these fake types slows down
the build and wastes space: the go tool binary size is 13MB
instead of 12MB, and the package size on amd64 is 48.7MB instead
of 45.3MB.
runtime: avoid inconsistent goroutine state in profiler
Because profiling signals can arrive at any time, we must
handle the case where a profiling signal arrives halfway
through a goroutine switch. Luckily, although there is much
to think through, very little needs to change.
Dave Cheney [Fri, 13 Sep 2013 05:01:22 +0000 (15:01 +1000)]
syscall: add TCIOFLUSH family of constants
Fixes #6355.
zerrors_linux_{386,amd64,arm}.go were regenerated using mkerrors.sh but I opted to add the three TC.*FLUSH lines by hand to keep the diff smaller and avoid problems with the API checker.
I'll check freebsd and darwin, could I ask for help with net/open bsd.
Rob Pike [Fri, 13 Sep 2013 02:44:45 +0000 (12:44 +1000)]
text/template/parse: mostly roll back the error detection for unmatched right delimiters
It's too late to change this behavior: it breaks templates with minimized JavaScript.
Makes me sad because this common error can never be caught: "{foo}}".
Three cheers for compatibility.
cmd/go: do not support code.google.com/r/zzz projects
This reverts CL 13261048. I have just learned that these are
no longer supported on code.google.com (that is, it is impossible
to create them), so there is little reason to add support in
Go 1.2.
Update #5408
R=golang-dev, dave, r
CC=golang-dev
https://golang.org/cl/13317046
runtime, cmd/gc, cmd/ld: ignore method wrappers in recover
Bug #1:
Issue 5406 identified an interesting case:
defer iface.M()
may end up calling a wrapper that copies an indirect receiver
from the iface value and then calls the real M method. That's
two calls down, not just one, and so recover() == nil always
in the real M method, even during a panic.
[For the purposes of this entire discussion, a wrapper's
implementation is a function containing an ordinary call, not
the optimized tail call form that is somtimes possible. The
tail call does not create a second frame, so it is already
handled correctly.]
Fix this bug by introducing g->panicwrap, which counts the
number of bytes on current stack segment that are due to
wrapper calls that should not count against the recover
check. All wrapper functions must now adjust g->panicwrap up
on entry and back down on exit. This adds slightly to their
expense; on the x86 it is a single instruction at entry and
exit; on the ARM it is three. However, the alternative is to
make a call to recover depend on being able to walk the stack,
which I very much want to avoid. We have enough problems
walking the stack for garbage collection and profiling.
Also, if performance is critical in a specific case, it is already
faster to use a pointer receiver and avoid this kind of wrapper
entirely.
Bug #2:
The old code, which did not consider the possibility of two
calls, already contained a check to see if the call had split
its stack and so the panic-created segment was one behind the
current segment. In the wrapper case, both of the two calls
might split their stacks, so the panic-created segment can be
two behind the current segment.
Fix this by propagating the Stktop.panic flag forward during
stack splits instead of looking backward during recover.
go/token: rename RemoveLine to MergeLine, improve documentation
This is a follow-up to feedback from gri in
https://golang.org/cl/12837044/. Most of the wording
and naming improvements are lifted shamelessly from him.
Nicholas Sullivan [Thu, 12 Sep 2013 16:23:34 +0000 (12:23 -0400)]
crypto/x509: allow ECDSA public keys to be marshaled.
The public key serialization from CreateCertificate is factored out to be
used in MarshalPKIXPublicKey.
Testcode with one P224 ECDSA keypair has been added.
Rob Pike [Thu, 12 Sep 2013 03:22:56 +0000 (13:22 +1000)]
text/template: catch unmatched right delimiter
It was simply a missing error case: when scanning plain text
outside of an action, a right delimiter should be an error.
Reduces a number of trials but it still can detect memory leak
when we make blunders in runtime-integarted network poller work,
like just forgetting to call runtime_pollClose in code paths.
Also disables the test on windows/386.
R=alex.brainman, r
CC=golang-dev
https://golang.org/cl/13022046
cmd/gc: inline copy in frontend to call memmove directly.
A new node type OSPTR is added to refer to the data pointer of
strings and slices in a simple way during walk(). It will be
useful for future work on simplification of slice arithmetic.
««« original CL description
cmd/5g, cmd/6g, cmd/8g: faster compilation
Replace linked list walk with memset.
This reduces CPU time taken by 'go install -a std' by ~10%.
Before:
real user sys
0m23.561s 0m16.625s 0m5.848s
0m23.766s 0m16.624s 0m5.846s
0m23.742s 0m16.621s 0m5.868s
after:
0m22.714s 0m14.858s 0m6.138s
0m22.644s 0m14.875s 0m6.120s
0m22.604s 0m14.854s 0m6.081s
R=golang-dev, r
CC=golang-dev
https://golang.org/cl/13084043
»»»
Asking about runtime/cgo when CgoEnabled=false now correctly
returns an error from build.Import (specifically, NoGoError), because
there are no buildable Go files in that directory.
The API tool was depending on it returning a package with no Go
files instead. Correct that assumption.
Fixes all.bash on local machines.
(Dashboard appears not to be running the api tool at all.)
««« original CL description
cmd/api: break the builds
There is some question about whether the api tool is
running on Windows (see issue 6124), and now I'm
starting to question whether it runs on any of the builders,
since both darwin/amd64 and linux/amd64 are crashing for me
in the api tool due to a recent cgo-related change, and yet
the dashboard is happy.
If the dashboard is still happy after this CL, we have a problem.
There is some question about whether the api tool is
running on Windows (see issue 6124), and now I'm
starting to question whether it runs on any of the builders,
since both darwin/amd64 and linux/amd64 are crashing for me
in the api tool due to a recent cgo-related change, and yet
the dashboard is happy.
If the dashboard is still happy after this CL, we have a problem.
frame is not necessary anymore, but we might some day
get back to functions where the frame size does not vary
by program counter, and if so we'll need it. Avoid needing
to introduce a new struct format later by keeping it now.
go/build: reject directory with only cgo files if cgo not in use
The old test for "no Go files" was p.Name == "", meaning we never
saw a Go package statement. That test fails if there are cgo files
that we parsed (and recorded the package name) but then chose
not to use (because cgo is not available).
Ian Lance Taylor [Wed, 11 Sep 2013 16:01:47 +0000 (09:01 -0700)]
cmd/yacc: replace units example with simpler expr example
The units example is nice but is covered by the Lucent
license, which may be a concern for some people making a
commercial source code distribution of Go.
R=golang-dev, r
CC=golang-dev
https://golang.org/cl/13283045
The various throwing > 0 finish a change started
in a previous CL, which sets throwing = -1 to mean
"don't show the internals". That gets set during the
"all goroutines are asleep - deadlock!" crash, and it
should also be set during any other expected crash
that does not indicate a problem within the runtime.
Most runtime.throw do indicate a problem within the
runtime, however, so we should be able to enumerate
the ones that should be silent. The goroutine sleeping
deadlock is the only one I can think of.
Otherwise, if panic starts running deferred functions,
the code that panicked appears to be calling those
functions directly, which is not the case and can be
confusing.
net: implement TCP connection setup with fast failover
This CL adds minimal support of Happy Eyeballs-like TCP connection
setup to Dialer API. Happy Eyeballs and derivation techniques are
described in the following:
- Happy Eyeballs: Success with Dual-Stack Hosts
http://tools.ietf.org/html/rfc6555
- Analysing Dual Stack Behaviour and IPv6 Quality
http://www.potaroo.net/presentations/2012-04-17-dual-stack-quality.pdf
Usually, the techniques consist of three components below.
- DNS query racers, that run A and AAAA queries in parallel or series
- A short list of destination addresses
- TCP SYN racers, that run IPv4 and IPv6 transport in parallel or series
This CL implements only the latter two. The existing DNS query
component gathers together A and AAAA records in series, so we don't
touch it here. This CL just uses extended resolveInternetAddr and makes
it possible to run multiple Dial racers in parallel.
For example, when the given destination is a DNS name and the name has
multiple address family A and AAAA records, and it happens on the TCP
wildcard network "tcp" with DualStack=true like the following:
cmd/go: report correct directory for 'no version control'
The scan starts at the directory we care about and works
backward to the GOPATH root. The error should say the
original directory name, not the name of the GOPATH root.