e.g., don't delete /dev/null. this fix inspired by gnu libiberty,
unlink-if-ordinary.c.
Fixes#7563
LGTM=iant
R=golang-codereviews, iant, 0intro
CC=golang-codereviews, r
https://golang.org/cl/76810045
On DragonFly BSD, we adjust the ephemeral port range because
unlike other BSD systems its default ephemeral port range
doesn't conform to IANA recommendation as described in RFC 6355
and is pretty narrow.
On DragonFly BSD 3.6: default range [1024, 5000], high range [49152, 65535]
On FreeBSD 10: default range [10000, 65535], high range [49152, 65535]
On Linux 3.11: default range [32768, 61000]
Fixes#7541.
LGTM=iant
R=jsing, gobot, iant
CC=golang-codereviews
https://golang.org/cl/80610044
SendmsgN is an alternate version Sendmsg that also returns
the number of bytes transferred, instead of just the error.
Update #7645
LGTM=aram, iant
R=iant, aram, bradfitz
CC=golang-codereviews
https://golang.org/cl/81210043
chanrecv now expects a pointer to the data to be filled in.
mapiterinit expects a pointer to the hash iterator to be filled in.
In both cases, the temporary being pointed at changes from
dead to alive during the call. In order to make sure it is
preserved if a garbage collection happens after that transition
but before the call returns, the temp must be marked as live
during the entire call.
But if it is live during the entire call, it needs to be safe for
the garbage collector to scan at the beginning of the call,
before the new data has been filled in. Therefore, it must be
zeroed by the caller, before the call. Do that.
My previous attempt waited to mark it live until after the
call returned, but that's unsafe (see first paragraph);
undo that change in plive.c.
This makes powser2 pass again reliably.
I looked at every call to temp in the compiler.
The vast majority are followed immediately by an
initialization of temp, so those are fine.
The only ones that needed changing were the ones
where the next operation is to pass the address of
the temp to a function call, and there aren't too many.
Maps are exempted from this because mapaccess
returns a pointer to the data and lets the caller make
the copy.
Fixes many builds.
TBR=khr
CC=golang-codereviews
https://golang.org/cl/80700046
This change sets systemSkip on a test where Go and CAPI have different
chain building behaviour. CAPI is correct, but aligning the Go code is
probably too large a change prior to 1.3.
LGTM=bradfitz
R=golang-codereviews, bradfitz
CC=golang-codereviews
https://golang.org/cl/81620043
For now we strictly use IPV6_V6ONLY=1 for IPv6-only communications
and IPV6_V6ONLY=0 for both IPv4 and IPv6 communications. So let the
capability test do the same.
LGTM=iant
R=golang-codereviews, gobot, iant
CC=golang-codereviews
https://golang.org/cl/80140044
The root update on 3/11/2014 removed the Verisign root cert that the Go
tests use. This only affects the 'TestSystemVerify' test in
crypto/x509.
Fixes#7523.
LGTM=bradfitz
R=golang-codereviews, bradfitz
CC=golang-codereviews
https://golang.org/cl/80000044
cgo represents all 0-sized and unsized types internally as [0]byte. This means that pointers to incomplete types would be interchangable, even if given a name by typedef.
Fixes#7409.
LGTM=iant
R=golang-codereviews, bradfitz, iant
CC=golang-codereviews
https://golang.org/cl/76450043
This is the same check we use during stack copying.
The check cannot be applied to C stack frames, even
though we do emit pointer bitmaps for the arguments,
because (1) the pointer bitmaps assume all arguments
are always live, not true of outputs during the prologue,
and (2) the pointer bitmaps encode interface values as
pointer pairs, not true of interfaces holding integers.
For the rest of the frames, however, we should hold ourselves
to the rule that a pointer marked live really is initialized.
The interface scanning already implicitly checks this
because it interprets the type word as a valid type pointer.
This may slow things down a little because of the extra loads.
Or it may speed things up because we don't bother enqueuing
nil pointers anymore. Enough of the rest of the system is slow
right now that we can't measure it meaningfully.
Enable for now, even if it is slow, to shake out bugs in the
liveness bitmaps, and then decide whether to turn it off
for the Go 1.3 release (issue 7650 reminds us to do this).
The new m->traceback field lets us force printing of fp=
values on all goroutine stack traces when we detect a
bad pointer. This makes it easier to understand exactly
where in the frame the bad pointer is, so that we can trace
it back to a specific variable and determine what is wrong.
Update #7650
LGTM=khr
R=khr
CC=golang-codereviews
https://golang.org/cl/80860044
1. On entry to a function, only zero the ambiguously live stack variables.
Before, we were zeroing all stack variables containing pointers.
The zeroing is pretty inefficient right now (issue 7624), but there are also
too many stack variables detected as ambiguously live (issue 7345),
and that must be addressed before deciding how to improve the zeroing code.
(Changes in 5g/ggen.c, 6g/ggen.c, 8g/ggen.c, gc/pgen.c)
Fixes#7647.
2. Make the regopt word-based liveness analysis preserve the
whole-variable liveness property expected by the garbage collection
bitmap liveness analysis. That is, if the regopt liveness decides that
one word in a struct needs to be preserved, make sure it preserves
the entire struct. This is particularly important for multiword values
such as strings, slices, and interfaces, in which all the words need
to be present in order to understand the meaning.
(Changes in 5g/reg.c, 6g/reg.c, 8g/reg.c.)
Fixes#7591.
3. Make the regopt word-based liveness analysis treat a variable
as having its address taken - which makes it preserved across
all future calls - whenever n->addrtaken is set, for consistency
with the gc bitmap liveness analysis, even if there is no machine
instruction actually taking the address. In this case n->addrtaken
is incorrect (a nicer way to put it is overconservative), and ideally
there would be no such cases, but they can happen and the two
analyses need to agree.
(Changes in 5g/reg.c, 6g/reg.c, 8g/reg.c; test in bug484.go.)
Fixes crashes found by turning off "zero everything" in step 1.
4. Remove spurious VARDEF annotations. As the comment in
gc/pgen.c explains, the VARDEF must immediately precede
the initialization. It cannot be too early, and it cannot be too late.
In particular, if a function call sits between the VARDEF and the
actual machine instructions doing the initialization, the variable
will be treated as live during that function call even though it is
uninitialized, leading to problems.
(Changes in gc/gen.c; test in live.go.)
Fixes crashes found by turning off "zero everything" in step 1.
5. Do not treat loading the address of a wide value as a signal
that the value must be initialized. Instead depend on the existence
of a VARDEF or the first actual read/write of a word in the value.
If the load is in order to pass the address to a function that does
the actual initialization, treating the load as an implicit VARDEF
causes the same problems as described in step 4.
The alternative is to arrange to zero every such value before
passing it to the real initialization function, but this is a much
easier and more efficient change.
(Changes in gc/plive.c.)
Fixes crashes found by turning off "zero everything" in step 1.
6. Treat wide input parameters with their address taken as
initialized on entry to the function. Otherwise they look
"ambiguously live" and we will try to emit code to zero them.
(Changes in gc/plive.c.)
Fixes crashes found by turning off "zero everything" in step 1.
7. An array of length 0 has no pointers, even if the element type does.
Without this change, the zeroing code complains when asked to
clear a 0-length array.
(Changes in gc/reflect.c.)
LGTM=khr
R=khr
CC=golang-codereviews
https://golang.org/cl/80160044
Zeroing the outputs makes sure that during function calls
in those functions we do not let the garbage collector
treat uninitialized values as pointers.
The garbage collector may still see uninitialized values
if a preemption occurs during the function prologue,
before the zeroing has had a chance to run.
This reduces the number of 'bad pointer' messages when
that runtime check is enabled, but it doesn't fix all of them,
so the check is still disabled.
It will also avoid leaks, although I doubt any of these were
particularly serious.
LGTM=iant, khr
R=iant, khr
CC=golang-codereviews
https://golang.org/cl/80850044
This was added by the one-pass CL (post Go 1.2)
so it can still be removed.
Removing because surely there will be new operations
added later, and we can't change the constant value
once we define it, so "last" is a bad concept to expose.
Nothing uses it.
LGTM=bradfitz
R=golang-codereviews, bradfitz
CC=golang-codereviews
https://golang.org/cl/81160043
The garbage collector will scan these pointers,
so make sure they are initialized.
LGTM=bradfitz, khr
R=khr, bradfitz
CC=golang-codereviews
https://golang.org/cl/80960047
If you compile a program that has cgo LDFLAGS directives, those are exported to an environment variable to be used by subsequent compiler tool invocations. The linking phase when using the gccgo toolchain did not consider the envvar CGO_LDFLAGS's linking directives resulting in undefined references when using cgo+gccgo.
Fixes#7573
LGTM=iant
R=golang-codereviews, iant
CC=golang-codereviews
https://golang.org/cl/80780043
GCC on OS X 10.6 doesn't support -Wuninitialized without -O.
Fixes#7492.
LGTM=iant
R=golang-codereviews, dave, iant
CC=golang-codereviews
https://golang.org/cl/72360045
m->moreargp/morebuf were not cleared in case of preemption and stack growing,
it can lead to persistent leaks of large memory blocks.
It seems to fix the sync.Pool finalizer failures. I've run the test 500'000 times
w/o a single failure; previously it would fail dozens of times.
Fixes#7633.
Fixes#7533.
LGTM=rsc
R=golang-codereviews
CC=golang-codereviews, khr, rsc
https://golang.org/cl/80480044
Update channel race annotations to support change in
cl/75130045: doc: allow buffered channel as semaphore without initialization
The new annotations are added only for channels with capacity 1.
Strictly saying it's possible to construct a counter-example that
will produce a false positive with capacity > 1. But it's hardly can
lead to false positives in real programs, at least I would like to see such programs first.
Any additional annotations also increase probability of false negatives,
so I would prefer to add them lazily.
LGTM=rsc
R=golang-codereviews
CC=golang-codereviews, iant, khr, rsc
https://golang.org/cl/76970043
Currently it's possible that bgsweep finishes before all spans
have been swept (we only know that sweeping of all spans has *started*).
In such case bgsweep may fail wake up runfinq goroutine when it needs to.
finq may still be nil at this point, but some finalizers may be queued later.
Make bgsweep to wait for sweeping to *complete*, then it can decide
whether it needs to wake up runfinq for sure.
Update #7533
LGTM=rsc
R=rsc
CC=golang-codereviews
https://golang.org/cl/75960043
If we set obj, then it will be enqueued for marking at the end of the scanning loop.
This is not necessary, since we've already marked it.
This can wait for 1.4 if you wish.
LGTM=rsc
R=rsc
CC=golang-codereviews
https://golang.org/cl/80030043
Fixes#7627.
CL 61970044 changed the order in which .a files are passed to gccgo's link phase. However by reversing the order it caused gccgo to complain if both internal (liba.a) and external (liba_test.a) versions of a package were presented as the former would not contain all the necessary symbols, and the latter would duplicate symbols already defined.
This change ensures that all 'fake' targets remain at the top of the final link order which should be fine as a package compiled as an external test is a superset of its internal sibling.
Looking at how gcToolchain links tests I think this change now accurately mirrors those actions which present $WORK/_test before $WORK in the link order.
LGTM=iant
R=rsc, iant
CC=golang-codereviews, michael.hudson
https://golang.org/cl/80300043
Some platform that implements inp_localgroup-like shared internet
protocol control block group looks a bit sensitive about transport
layer protocol's address:port reuse. Sometimes it rejects a TCP SYN
packet using TCP RST, and sometimes silence.
For now, until test case refactoring, we admit few Dial failures on
TestTCPConcurrentAccept as a workaround.
Update #7400
Update #7541
LGTM=jsing
R=jsing
CC=golang-codereviews
https://golang.org/cl/75920043
The previous fix CL 69340044 still leaves a possibility of it.
This CL prevents the kernel, especially DragonFly BSD, from
performing unpredictable asynchronous connection establishment
on stream-based transport layer protocol sockets.
Update #7541
Update #7474
LGTM=jsing
R=jsing
CC=golang-codereviews
https://golang.org/cl/75930043
Disable it until it's debugged so it doesn't hide other real
problems on Windows. The test was known to be unreliable
anyway (which is why it only needed 1 of 20 runs to pass), but
apparently it never passes on Windows. Figure out why later.
Update #7634
LGTM=alex.brainman
R=adg, alex.brainman
CC=golang-codereviews
https://golang.org/cl/80110043
Change two-bit stack map entries to encode:
0 = dead
1 = scalar
2 = pointer
3 = multiword
If multiword, the two-bit entry for the following word encodes:
0 = string
1 = slice
2 = iface
3 = eface
That way, during stack scanning we can check if a string
is zero length or a slice has zero capacity. We can avoid
following the contained pointer in those cases. It is safe
to do so because it can never be dereferenced, and it is
desirable to do so because it may cause false retention
of the following block in memory.
Slice feature turned off until issue 7564 is fixed.
Update #7549
LGTM=rsc
R=golang-codereviews, bradfitz, rsc
CC=golang-codereviews
https://golang.org/cl/76380043
The existing code did not have a clear notion of whether
memory has been actually reserved. It checked based on
whether in 32-bit mode or 64-bit mode and (on GNU/Linux) the
requested address, but it confused the requested address and
the returned address.
LGTM=rsc
R=rsc, dvyukov
CC=golang-codereviews, michael.hudson
https://golang.org/cl/79610043
This the second part of making persistent HTTPS connections to
certain servers (notably Amazon) robust.
See the story in part 1: https://golang.org/cl/76400046/
This is the http Transport change that notes whether our
net.Conn.Read has ever seen an EOF. If it has, then we use
that as an additional signal to not re-use that connection (in
addition to the HTTP response headers)
Fixes#3514
LGTM=rsc
R=agl, rsc
CC=golang-codereviews
https://golang.org/cl/79240044
Update #3514
An io.Reader is permitted to return either (n, nil)
or (n, io.EOF) on EOF or other error.
The tls package previously always returned (n, nil) for a read
of size n if n bytes were available, not surfacing errors at
the same time.
Amazon's HTTPS frontends like to hang up on clients without
sending the appropriate HTTP headers. (In their defense,
they're allowed to hang up any time, but generally a server
hangs up after a bit of inactivity, not immediately.) In any
case, the Go HTTP client tries to re-use connections by
looking at whether the response headers say to keep the
connection open, and because the connection looks okay, under
heavy load it's possible we'll reuse it immediately, writing
the next request, just as the Transport's always-reading
goroutine returns from tls.Conn.Read and sees (0, io.EOF).
But because Amazon does send an AlertCloseNotify record before
it hangs up on us, and the tls package does its own internal
buffering (up to 1024 bytes) of pending data, we have the
AlertCloseNotify in an unread buffer when our Conn.Read (to
the HTTP Transport code) reads its final bit of data in the
HTTP response body.
This change makes that final Read return (n, io.EOF) when
an AlertCloseNotify record is buffered right after, if we'd
otherwise return (n, nil).
A dependent change in the HTTP code then notes whether a
client connection has seen an io.EOF and uses that as an
additional signal to not reuse a HTTPS connection. With both
changes, the majority of Amazon request failures go
away. Without either one, 10-20 goroutines hitting the S3 API
leads to such an error rate that empirically up to 5 retries
are needed to complete an API call.
LGTM=agl, rsc
R=agl, rsc
CC=golang-codereviews
https://golang.org/cl/76400046
The nproc and ndone fields are uint32. This makes the type
consistent.
LGTM=minux.ma
R=golang-codereviews, minux.ma
CC=golang-codereviews
https://golang.org/cl/79340044
Strictly speaking, it's not necessary in example_test.go, as the
Rows.Close docs say that "If Next returns false, the Rows are closed
automatically". However, if the for loop breaks or returns early, it's
not obvious that you'll leak unless you explicitly call Rows.Close.
LGTM=bradfitz
R=bradfitz
CC=golang-codereviews, rsc
https://golang.org/cl/79330043
Structured Exception Handling (SEH) was the first way to handle
exceptions (memory faults, divides by zero) on Windows.
The S might as well stand for "stack-based": the implementation
interprets stack addresses in a few different ways, and it gets
subtly confused by Go's management of stacks. It's also something
that requires active maintenance during cgo switches, and we've
had bugs in that maintenance in the past.
We have recently come to believe that SEH cannot work with
Go's stack usage. See http://golang.org/issue/7325 for details.
Vectored Exception Handling (VEH) is more like a Unix signal
handler: you set it once for the whole process and forget about it.
This CL drops all the SEH code and replaces it with VEH code.
Many special cases and 7 #ifdefs disappear.
VEH was introduced in Windows XP, so Go on windows/386 will
now require Windows XP or later. The previous requirement was
Windows 2000 or later. Windows 2000 immediately preceded
Windows XP, so Windows 2000 is the only affected version.
Microsoft stopped supporting Windows 2000 in 2010.
See http://golang.org/s/win2000-golang-nuts for details.
Fixes#7325.
LGTM=alex.brainman, r
R=golang-codereviews, alex.brainman, stephen.gutekanst, dave
CC=golang-codereviews, iant, r
https://golang.org/cl/74790043
This has come up twice now. Redirect future questions
to the explanation in the issue tracker.
LGTM=iant, r
R=r, iant
CC=golang-codereviews
https://golang.org/cl/79550043
Currently it's always zero, but that is inconsistent with math.Pow
and also plain wrong.
This is a proposal for how it should be defined.
Fixes#7583.
LGTM=rsc
R=golang-codereviews, iant, gobot, rsc
CC=golang-codereviews
https://golang.org/cl/76940044
ReadFrom should not return until it receives a non-nil error
or too many contiguous (0, nil)s from a given reader.
Currently it immediately returns if it receives one (0, nil).
Fixes#7611.
LGTM=bradfitz
R=golang-codereviews, bradfitz
CC=golang-codereviews
https://golang.org/cl/76400048
bi is a slice and not an array, so bi[:] does not make much sense.
LGTM=bradfitz
R=golang-codereviews, bradfitz
CC=golang-codereviews
https://golang.org/cl/79280043
It's a little bit waste to check if r is not a surrogate
code point because RuneError is not a surrogate code point.
LGTM=iant
R=golang-codereviews, iant
CC=golang-codereviews
https://golang.org/cl/79230043
"min" and "max" in "case '{'" clause are fresh variables.
The variables defined in the outer scope never get value
other than 0.
LGTM=bradfitz
R=golang-codereviews, bradfitz
CC=golang-codereviews
https://golang.org/cl/78750044
Currently Scan ignores an error returned from source if the number
of bytes source has read is 0.
Fixes#7594.
LGTM=gri
R=golang-codereviews, bradfitz, gri
CC=golang-codereviews
https://golang.org/cl/78120043
Revision 3ae4607a43ff introduced CONVNOP layers
to fix type checking issues arising from comparisons.
The added complexity made 8g run out of registers
when compiling an equality function in go.net/ipv6.
A similar issue occurred in test/sizeof.go on
amd64p32 with 6g.
Fixes#7405.
LGTM=khr
R=rsc, dave, iant, khr
CC=golang-codereviews
https://golang.org/cl/78100044
Encoding.Decode() failed to detect trailing garbages if input contains "==" followed by garbage smaller than 3 bytes (for example, it failed to detect "x" in "AA==x"). This patch fixes the bug and adds a few tests.
LGTM=nigeltao
R=golang-codereviews, bradfitz, nigeltao
CC=golang-codereviews
https://golang.org/cl/75340044
Removes most uses of the REP prefix, which has a high startup cost.
LGTM=iant
R=golang-codereviews, iant, khr
CC=golang-codereviews
https://golang.org/cl/77920043
Rationale:
It already is for scanning.
It is accepted for complexes already, but doesn't work.
It's analogous to %G and %E.
C accepts it too, and we try to be roughly compatible.
Fixes#7518.
LGTM=bradfitz
R=golang-codereviews, bradfitz
CC=golang-codereviews
https://golang.org/cl/77580044
CL 77580046 caused a data race issue with tests that assumes ReadAt
does not mutate receiver. This patch partially revert CL 77580046
to fix it.
LGTM=bradfitz
R=golang-codereviews, bradfitz
CC=golang-codereviews
https://golang.org/cl/77900043
These test cases are redundant because TestSimpleFold tests
all possible rotations of test data, so no need to add
rotated strings.
Also updated the comment as it's guaranteed that SimpleFold
returns values in increasing order.
LGTM=bradfitz
R=golang-codereviews, bradfitz
CC=golang-codereviews
https://golang.org/cl/77730043
UnreadRune should return an error if previous operation is not
ReadRune.
Fixes#7579.
LGTM=bradfitz
R=golang-codereviews, bradfitz
CC=golang-codereviews
https://golang.org/cl/77580046
Also move generated code into a separate file,
because it's difficult to work with the file otherwise.
LGTM=khr
R=golang-codereviews, khr
CC=golang-codereviews
https://golang.org/cl/76080044
A too large float constant is an error.
A too small float constant is rounded to zero.
Fixes#7419
Update #6902
LGTM=iant
R=golang-codereviews, iant
CC=golang-codereviews
https://golang.org/cl/76730046
utf8.RuneLen returns -1 for an invalid rune. In that case we
need to extend the internal buffer at least by 3 for \uFFFD.
Fixes#7577.
LGTM=iant
R=golang-codereviews, iant
CC=golang-codereviews
https://golang.org/cl/77420044
See testing.FailNow for further information.
Also avoid nil pointer derefernce in TestTransportMaxPerHostIdleConns.
LGTM=dave
R=golang-codereviews, dave
CC=golang-codereviews
https://golang.org/cl/76470043
"nn" can never be zero for any input "p", so no check is needed.
This change should improve readability a bit.
LGTM=nigeltao
R=golang-codereviews, bradfitz, nigeltao
CC=golang-codereviews
https://golang.org/cl/76610045
%q quotes each element of a string slice; this was never explained in the docs.
Fixes#7015.
LGTM=josharian
R=golang-codereviews, josharian
CC=golang-codereviews
https://golang.org/cl/77140044
Request ID reuse is allowed by the FastCGI spec [1]. In particular nginx uses
the same request ID, 1, for all requests on a given connection. Because
serveRequest does not remove the request from conn.requests, this causes it to
treat the second request as a duplicate and drops the connection immediately
after beginRequest. This manifests with nginx option 'fastcgi_keep_conn on' as
the following message in nginx error log:
2014/03/17 01:39:13 [error] 730#0: *109 recv() failed (104: Connection reset by peer) while reading response header from upstream, client: x.x.x.x, server: example.org, request: "GET / HTTP/1.1", upstream: "fastcgi://127.0.0.1:9001", host: "example.org"
Because handleRecord and serveRequest run in different goroutines, access to
conn.requests must now be synchronized.
[1] http://www.fastcgi.com/drupal/node/6?q=node/22#S3.3
LGTM=bradfitz
R=bradfitz
CC=golang-codereviews
https://golang.org/cl/76800043
I believe the original author of this code just forgot to check for error here.
LGTM=bradfitz
R=golang-codereviews, bradfitz
CC=golang-codereviews
https://golang.org/cl/76760043
It was using the wrong offset and returned random values
making "runoutput" compiler tests crash.
LGTM=iant
R=golang-codereviews, iant
CC=golang-codereviews
https://golang.org/cl/76250043
They were rejected by NaCl due to AES instructions and
accesses to %gs:0x8, caused by wrong tlsoffset value.
LGTM=iant
R=rsc, dave, iant
CC=golang-codereviews
https://golang.org/cl/76050044
It's possible that bgsweep constantly does not catch up for some reason,
in this case runfinq was not woken at all.
R=rsc
CC=golang-codereviews
https://golang.org/cl/75940043
The problem was that spans end up in wrong lists after split
(e.g. in h->busy instead of h->central->empty).
Also the span can be non-swept before split,
I don't know what it can cause, but it's safer to operate on swept spans.
Fixes#7544.
R=golang-codereviews, rsc
CC=golang-codereviews, khr
https://golang.org/cl/76160043
Currently processes crash with obscure message.
Say that it's "out of memory".
LGTM=rsc
R=golang-codereviews
CC=golang-codereviews, khr, rsc
https://golang.org/cl/75820045
Old versions of DTrace (as those shipped in OS X and FreeBSD)
don't support unicode characters in symbol names. Replace '·'
to '.' to make DTrace happy.
Fixes#7493
LGTM=aram, rsc
R=aram, rsc, gobot, iant
CC=golang-codereviews
https://golang.org/cl/72280043
The Solaris network poller uses event ports, which are
level-triggered. As such, it has to re-arm itself after each
wakeup. The arming mechanism (which runs in its own thread) raced
with the closing of a file descriptor happening in a different
thread. When a network file descriptor is about to be closed,
the network poller is awaken to give it a chance to remove its
association with the file descriptor. Because the poller always
re-armed itself, it raced with code that closed the descriptor.
This change makes the network poller check before re-arming if
the file descriptor is about to be closed, in which case it will
ignore the re-arming request. It uses the per-PollDesc lock in
order to serialize access to the PollDesc.
This change also adds extensive documentation describing the
Solaris implementation of the network poller.
Fixes#7410.
LGTM=dvyukov, iant
R=golang-codereviews, bradfitz, iant, dvyukov, aram.h, gobot
CC=golang-codereviews
https://golang.org/cl/69190044
debug/elf does the same thing, use []byte{} for
any missing sections.
Fixes#7510
LGTM=rsc
R=golang-codereviews, iant
CC=golang-codereviews, rsc
https://golang.org/cl/75230043
Mark free memory blocks as unused.
On amd64 it allows the process to eat all 128 GB of heap
without killing the machine.
LGTM=rsc
R=rsc
CC=golang-codereviews
https://golang.org/cl/74070043
This is especially important for SetPanicOnCrash,
but also useful for e.g. nil deref in mallocgc.
Panics on such crashes can't lead to anything useful,
only to deadlocks, hangs and obscure crashes.
This is a copy of broken but already LGTMed
https://golang.org/cl/68540043/
TBR=rsc
R=rsc
CC=golang-codereviews
https://golang.org/cl/75320043
When we copy stack, we check only new size of the top segment.
This is incorrect, because we can have other segments below it.
LGTM=khr
R=golang-codereviews, khr
CC=golang-codereviews, rsc
https://golang.org/cl/73980045
Calling runtime·cgocall could trigger a GC in the child while
gclock was held by the parent.
Fixes#7511
LGTM=bradfitz, dvyukov, dave
R=golang-codereviews, bradfitz, dvyukov, dave
CC=golang-codereviews, rsc
https://golang.org/cl/75210044
The lowering to runtime calls introduces hidden pointers to the
arguments of select clauses. When implicit conversions were
involved it could end up with incompatible pointers. Since the
pointed-to types have the same representation, we can introduce a
forced conversion.
Fixes#6847.
LGTM=rsc
R=rsc, iant, khr
CC=golang-codereviews
https://golang.org/cl/72380043
It was using a REP STOSQ but putting in CX the number of 32-bit
words to clear.
LGTM=dave
R=rsc, dave
CC=golang-codereviews
https://golang.org/cl/75240043
Under some circumstances, gccgoToolchain's ld can pass the path of
build outputs that have been deleted to the link command.
Fixes#7303.
LGTM=rsc
R=golang-codereviews, dave, michael.hudson, rsc
CC=golang-codereviews
https://golang.org/cl/61970044
The compilers expect to not be interrupted by floating
point exceptions. On Plan 9, every process starts with
interrupts enabled for invalid operation, stack overflow,
and divide by zero exceptions.
LGTM=rsc
R=rsc, 0intro
CC=golang-codereviews
https://golang.org/cl/72750043
Previously, we wrote "kill" to the process control file
to kill a program. This is problematic because it doesn't
let the program gracefully exit.
This matters especially if the process we're killing is a
Go program. On Unix, sending SIGKILL to a Go program will
automatically kill all runtime threads. On Plan 9, there
are no threads so when the program wants to exit it has to
somehow signal all of the runtime processes. It can't do
this if we mercilessly kill it by writing to it's control
file.
Instead, we now send it a note to invoke it's note handler
and let it perform any cleanup before exiting.
LGTM=rsc
R=rsc, 0intro
CC=golang-codereviews
https://golang.org/cl/74440044
On Plan 9, the kernel disallows the use of floating point
instructions while handling a note. Previously, we worked
around this by using a simple loop in place of memmove.
When I added that work-around, I verified that all paths
from the note handler didn't end up calling memmove. Now
that memclr is using SSE instructions, the same process
will have to be done again.
Instead of doing that, however, this CL just punts and
uses unoptimized functions everywhere on Plan 9.
LGTM=rsc
R=rsc, 0intro
CC=golang-codereviews
https://golang.org/cl/73830044
Acid can't produce a stack trace without .frame symbols.
Of course, it can only unwind through linear stacks but
this is still better than nothing. (I wrote an acid func
to do the full unwind a long time ago but lost it and
haven't worked up the courage to write it again).
Note that these will only be present in the native symbol
table for Plan 9 binaries.
LGTM=rsc
R=rsc
CC=golang-codereviews
https://golang.org/cl/72450045
syscall.naclWrite was missing from sys_nacl_386.s
This gets ./make.bash passing, but doesn't pass validation. I'm not sure if this is the fault of this change, or validation was broken anyway.
LGTM=rsc
R=minux.ma, rsc
CC=golang-codereviews
https://golang.org/cl/74510043
1. Fix the bug that shrinkstack returns memory to heap.
This causes growslice to misbehave (it manually initialized
blocks, and in efence mode shrinkstack's free leads to
partially-initialized blocks coming out of growslice.
Which in turn causes GC to crash while treating the garbage
as Eface/Iface.
2. Enable efence for stack segments.
LGTM=rsc
R=golang-codereviews, rsc
CC=golang-codereviews, khr
https://golang.org/cl/74080043
The garbage collector uses type information to guide the
traversal of the heap. If it sees a field that should be a string,
it marks the object pointed at by the string data pointer as
visited but does not bother to look at the data, because
strings contain bytes, not pointers.
If you save s[len(s):] somewhere, though, the string data pointer
actually points just beyond the string data; if the string data
were exactly the size of an allocated block, the string data
pointer would actually point at the next block. It is incorrect
to mark that next block as visited and not bother to look at
the data, because the next block may be some other type
entirely.
The fix is to ignore strings with zero length during collection:
they are empty and can never become non-empty: the base
pointer will never be used again. The handling of slices already
does this (but using cap instead of len).
This was not a bug in Go 1.2, because until January all string
allocations included a trailing NUL byte not included in the
length, so s[len(s):] still pointed inside the string allocation
(at the NUL).
This bug was causing the crashes in test/run.go. Specifically,
the parsing of a regexp in package regexp/syntax allocated a
[]syntax.Inst with rounded size 1152 bytes. In fact it
allocated many such slices, because during the processing of
test/index2.go it creates thousands of regexps that are all
approximately the same complexity. That takes a long time, and
test/run works on other tests in other goroutines. One such
other test is chan/perm.go, which uses an 1152-byte source
file. test/run reads that file into a []byte and then calls
strings.Split(string(src), "\n"). The string(src) creates an
1152-byte string - and there's a very good chance of it
landing next to one of the many many regexp slices already
allocated - and then because the file ends in a \n,
strings.Split records the tail empty string as the final
element in the slice. A garbage collection happens at this
point, the collection finds that string before encountering
the []syntax.Inst data it now inadvertently points to, and the
[]syntax.Inst data is not scanned for the pointers that it
contains. Each syntax.Inst contains a []rune, those are
missed, and the backing rune arrays are freed for reuse. When
the regexp is later executed, the runes being searched for are
no longer runes at all, and there is no match, even on text
that should match.
On 64-bit machines the pointer in the []rune inside the
syntax.Inst is larger (along with a few other pointers),
pushing the []syntax.Inst backing array into a larger size
class, avoiding the collision with chan/perm.go's
inadvertently sized file.
I expect this was more prevalent on OS X than on Linux or
Windows because those managed to run faster or slower and
didn't overlap index2.go with chan/perm.go as often. On the
ARM systems, we only run one errorcheck test at a time, so
index2 and chan/perm would never overlap.
It is possible that this bug is the root cause of other crashes
as well. For now we only know it is the cause of the test/run crash.
Many thanks to Dmitriy for help debugging.
Fixes#7344.
Fixes#7455.
LGTM=r, dvyukov, dave, iant
R=golang-codereviews, dave, r, dvyukov, delpontej, iant
CC=golang-codereviews, khr
https://golang.org/cl/74250043
debuglive >= 1 is not the condition under which we
start recording messages (we avoid printing for
init functions even if debuglive is set).
LGTM=bradfitz, iant
R=golang-codereviews, bradfitz
CC=golang-codereviews, iant, khr
https://golang.org/cl/74390043
For now Note, futexsleep and futexwakeup are designed for threads,
not for processes. The explicit use of UMTX_OP_WAIT_UINT_PRIVATE and
UMTX_OP_WAKE_PRIVATE can avoid unnecessary traversals of VM objects,
to hit undiscovered bugs related to VM system on SMP/SMT/NUMA
environment.
Update #7496
LGTM=iant
R=golang-codereviews, gobot, iant, bradfitz
CC=golang-codereviews
https://golang.org/cl/72760043
Solaris doesn't have struct ip_mreqn, instead it uses struct ip_mreq
and struct group_req with struct sockaddr_storage.
Also fixes incorrect SockaddrDatalink.
Update #7399
LGTM=aram, iant
R=golang-codereviews, aram, gobot, iant
CC=golang-codereviews
https://golang.org/cl/73920043
This CL is a reformulation of CL 73110043 containing only the minimum required to get the nacl builds compiling.
LGTM=bradfitz
R=rsc, bradfitz
CC=golang-codereviews
https://golang.org/cl/74220043
The comment for 'Clean' function is prepended with spaces instead of
a single tab, resulting in visually misaligned comment in the generated
documentation.
LGTM=bradfitz
R=golang-codereviews, bradfitz
CC=golang-codereviews
https://golang.org/cl/73840043
The change to signal_amd64.c from CL 15790043 was not merged correctly.
This CL reapplies the change, renaming the file to signal_amd64x.c and adds the appropriate build tags.
LGTM=iant, bradfitz
R=rsc, iant, bradfitz
CC=golang-codereviews
https://golang.org/cl/72790043
The byte that r is or'd into is already 0x7, so the failure to zero r only
impacts the generated machine code if the register is > 7.
Fixes#7044.
LGTM=dave, minux.ma, rsc
R=dave, minux.ma, bradfitz, rsc
CC=golang-codereviews
https://golang.org/cl/73730043
Spans are now private to threads, and the loop
is removed from all other functions.
Remove it from marknogc for consistency.
LGTM=khr, rsc
R=golang-codereviews, bradfitz, khr
CC=golang-codereviews, khr, rsc
https://golang.org/cl/72520043
Not many windows users have perl installed. They can just use
standard go tools instead. Also mkerrors_windows.sh script
removed - we don't add any new "unix" errors to windows
syscall package anymore.
LGTM=rsc
R=golang-codereviews, rsc
CC=golang-codereviews
https://golang.org/cl/41060044
Thanks to Ian for spotting these.
runtime.h: define uintreg correctly.
stack.c: address warning caused by the type of uintreg being 32 bits on amd64p32.
Commentary (mainly for my own use)
nacl/amd64p32 defines a machine with 64bit registers, but address space is limited to a 4gb window (the window is placed randomly inside the full 48 bit virtual address space of a process). To cope with this 6c defines _64BIT and _64BITREG.
_64BITREG is always defined by 6c, so both GOARCH=amd64 and GOARCH=amd64p32 use 64bit wide registers.
However _64BIT itself is only defined when 6c is compiling for amd64 targets. The definition is elided for amd64p32 environments causing int, uint and other arch specific types to revert to their 32bit definitions.
LGTM=iant
R=iant, rsc, remyoudompheng
CC=golang-codereviews
https://golang.org/cl/72860046
gc does not report this as an error, but go/types does.
(I suspect that constructing a closure counts as a reference
to &all in gc's implementation).
This is not a tool bug, since the spec doesn't require
implementations to implement this check, but it does
illustrate that dialect variations are always a nuisance.
LGTM=rsc, bradfitz
R=bradfitz
CC=golang-codereviews, gri, rsc
https://golang.org/cl/73850043
Previously, passing a long duration to ParseDuration could result in
random, even negative, values.
LGTM=r
R=golang-codereviews, bradfitz, r
CC=golang-codereviews
https://golang.org/cl/72120043
CL 69340044 requires that syscall.SO_ERROR be defined on all unix like platforms. Add SO_ERROR to the list of dummy constants in sycall/net_nacl.go.
LGTM=bradfitz
R=iant, rsc, mikioh.mikioh, bradfitz
CC=golang-codereviews
https://golang.org/cl/73100043
If we report a leak, make sure we've waited long enough to be sure.
The new sleep regimen waits 1.05 seconds before failing; the old
one waited 0.005 seconds.
(The single linux/amd64 failure in this test feels more like a
timing problem than a leak. I don't want to spend time on it unless
we're sure.)
LGTM=bradfitz
R=bradfitz
CC=golang-codereviews
https://golang.org/cl/72630043
We provide amd64p32 implementations for md5 and sha1 so we need to exclude amd64p32 from the generic implementations in those packages.
Fixes build once CL 72360044 lands.
LGTM=agl, remyoudompheng
R=rsc, bradfitz, agl, remyoudompheng
CC=golang-codereviews
https://golang.org/cl/72460043
This fixes the following amd64p32 issue:
pkg/time/format.go:724: internal compiler error: twobitwalktype1: invalid initial alignment, Time
caused by the pointer zone ending on a 32-bit-aligned boundary.
LGTM=rsc
R=rsc, dave
CC=golang-codereviews
https://golang.org/cl/72270046
This code being buggy is the only explanation I can come up
with for issue 7325. It's probably not, but the only alternative
is a Windows kernel bug. Comment this out to see what breaks
or gets fixed.
Update #7325
LGTM=bradfitz
R=golang-codereviews, bradfitz
CC=golang-codereviews
https://golang.org/cl/72590044
From the trace it appears that stackalloc is being
called with 0x1800 which is 6k = 4k + (StackSystem=2k).
Make StackSystem 4k too, to make stackalloc happy.
It's already 4k on windows/amd64.
TBR=khr
CC=golang-codereviews
https://golang.org/cl/72600043
It was using MOVL to pass a 64-bit argument
(concatenated framesize and argsize) to morestack11.
LGTM=dave, rsc
R=dave, rsc, iant
CC=golang-codereviews
https://golang.org/cl/72360044
There are at least 3 bugs:
1. g->stacksize accounting is broken during copystack/shrinkstack
2. stktop->free is not properly maintained during copystack/shrinkstack
3. stktop->free logic is broken:
we can have stktop->free==FixedStack,
and we will free it into stack cache,
but it actually comes from heap as the result of non-copying segment shrink
This shows as at least spurious races on race builders (maybe something else as well I don't know).
The idea behind the refactoring is to consolidate stacksize and
segment origin logic in stackalloc/stackfree.
Fixes#7490.
LGTM=rsc, khr
R=golang-codereviews, rsc, khr
CC=golang-codereviews
https://golang.org/cl/72440043
Recursive panics leave dangling Panic structs in g->panic stack.
At best it leads to a Defer leak and incorrect output on a subsequent panic.
At worst it arbitrary corrupts heap.
LGTM=rsc
R=rsc
CC=golang-codereviews
https://golang.org/cl/72480043
One reason the sync.Pool finalizer test can fail is that
this function's ef1 contains uninitialized data that just
happens to point at some of the old pool. I've seen this cause
retention of a single pool cache line (32 elements) on arm.
Really we need liveness information for C functions, but
for now we can be more careful about data in long-lived
C functions that block.
LGTM=bradfitz, dvyukov
R=golang-codereviews, bradfitz, dvyukov
CC=golang-codereviews, iant, khr
https://golang.org/cl/72490043
Replaces CL 70000043.
Switch to the amd64p32 linker model if we are building under nacl/amd64p32.
No need to introduce linkarchinit() as 6a contains its own main() function.
LGTM=rsc
R=rsc, minux.ma
CC=golang-codereviews
https://golang.org/cl/72020043
Replaces CL 70000043.
Introduce linkarchinit() from cmd/ld.
For cmd/6g, switch to the amd64p32 linker model if we are building under nacl/amd64p32.
LGTM=rsc
R=rsc
CC=golang-codereviews
https://golang.org/cl/71330045
Instead, split the underlying storage in half and
free just half of it.
Shrinking without copying lets us reclaim storage used
by a previously profligate Go routine that has now blocked
inside some C code.
To shrink in place, we need all stacks to be a power of 2 in size.
LGTM=rsc
R=golang-codereviews, rsc
CC=golang-codereviews
https://golang.org/cl/69580044
This is a test case for CL 34680044.
Fixes#6333.
LGTM=bradfitz
R=golang-codereviews, bradfitz, minux.ma
CC=golang-codereviews
https://golang.org/cl/71230049
Two memory allocator bug fixes.
- efence is not maintaining the proper heap metadata
to make eventual memory reuse safe, so use SysFault.
- now that our heap PageSize is 8k but most hardware
uses 4k pages, SysAlloc and SysReserve results must be
explicitly aligned. Do that in a few more call sites and
document this fact in malloc.h.
Fixes#7448.
LGTM=iant
R=golang-codereviews, josharian, iant
CC=dvyukov, golang-codereviews
https://golang.org/cl/71750048
Replaces CL 70000043.
Introduce linkarchinit() from cmd/ld.
For cmd/6c, switch to the amd64p32 linker model if we are building under nacl/amd64p32.
LGTM=rsc
R=rsc
CC=golang-codereviews
https://golang.org/cl/72010043
I've just needed the G status on fault to debug runtime bug.
For some reason we print everything except header here.
Make it more informative and consistent.
R=rsc
CC=golang-codereviews
https://golang.org/cl/67870056
Implement custom assembly thunks for hot race calls (memory accesses and function entry/exit).
The thunks extract caller pc, verify that the address is in heap or global and switch to g0 stack.
Before:
ok regexp 3.692s
ok compress/bzip2 9.461s
ok encoding/json 6.380s
After:
ok regexp 2.229s (-40%)
ok compress/bzip2 4.703s (-50%)
ok encoding/json 3.629s (-43%)
For comparison, normal non-race build:
ok regexp 0.348s
ok compress/bzip2 0.304s
ok encoding/json 0.661s
Race build:
ok regexp 2.229s (+540%)
ok compress/bzip2 4.703s (+1447%)
ok encoding/json 3.629s (+449%)
Also removes some race-related special cases from cgocall and scheduler.
In long-term it will allow to remove cyclic runtime/race dependency on cmd/cgo.
Fixes#4249.
Fixes#7460.
Update #6508
Update #6688
R=iant, rsc, bradfitz
CC=golang-codereviews
https://golang.org/cl/55100044
Tested GOARM=6 on Raspberry Pi, and I found only a few tests that
use sub-normal numbers fails. I have a patch to NetBSD kernel pending
that fixes this issue (NetBSD kernel doesn't allow us to disable the
Flush-to-Zero feature).
LGTM=jsing
R=golang-codereviews, jsing
CC=golang-codereviews
https://golang.org/cl/70730043
Essentialy for running tests without a working cmd/go.
While we're at it, also fix a typo.
LGTM=rsc
R=golang-codereviews, rsc
CC=golang-codereviews
https://golang.org/cl/70640043
During the glob decoding process interface values are set to concrete
values after a test for assignability. If the assignability test fails
a slightly vague error message is produced. While technically accurate
the error message does not clearly describe the problem.
Rewrite the error message to include the usage of the word assignable,
which makes it clear the concrete value type is not assignable to the
interface value type.
Fixes#6467.
LGTM=r
R=golang-codereviews, rsc, r
CC=golang-codereviews
https://golang.org/cl/71590043
Recently NetBSD starts to enforce this, and refuses to execute
the program if n is larger than the sum of entry sizes.
Before:
$ readelf -n ../bin/go.old
Notes at offset 0x00000bd0 with length 0x00000019:
Owner Data size Description
NetBSD 0x00000004 NT_VERSION (version)
readelf: Warning: corrupt note found at offset 18 into core notes
readelf: Warning: type: 0, namesize: 00000000, descsize: 00000000
$ readelf -n ../bin/go
Notes at offset 0x00000bd0 with length 0x00000018:
Owner Data size Description
NetBSD 0x00000004 NT_VERSION (version)
LGTM=iant
R=iant
CC=golang-codereviews
https://golang.org/cl/70710043
Add CgoFiles to the covered files when building
with cover support.
LGTM=rsc
R=golang-codereviews, gobot, r, rsc
CC=golang-codereviews
https://golang.org/cl/34680044
Apparently, the Windows routines sometimes fail to generate output.
Copy the Unix stdio-based implementations instead.
Suggested by Pietro Gagliardi in CL 65280043 but that CL
seems to have been abandoned.
Fixes#7242.
LGTM=bradfitz
R=golang-codereviews, bradfitz
CC=golang-codereviews
https://golang.org/cl/71550044
32-bit Windows uses "structured exception handling" (SEH) to
handle hardware faults: that there is a per-thread linked list
of fault handlers maintained in user space instead of
something like Unix's signal handlers. The structures in the
linked list are required to live on the OS stack, and the
usual discipline is that the function that pushes a record
(allocated from the current stack frame) onto the list pops
that record before returning. Not to pop the entry before
returning creates a dangling pointer error: the list head
points to a stack frame that no longer exists.
Go pushes an SEH record in the top frame of every OS thread,
and that record suffices for all Go execution on that thread,
at least until cgo gets involved.
If we call into C using cgo, that called C code may push its
own SEH records, but by the convention it must pop them before
returning back to the Go code. We assume it does, and that's
fine.
If the C code calls back into Go, we want the Go SEH handler
to become active again, not whatever C has set up. So
runtime.callbackasm1, which handles a call from C back into
Go, pushes a new SEH record before calling the Go code and
pops it when the Go code returns. That's also fine.
It can happen that when Go calls C calls Go like this, the
inner Go code panics. We allow a defer in the outer Go to
recover the panic, effectively wiping not only the inner Go
frames but also the C calls. This sequence was not popping the
SEH stack up to what it was before the cgo calls, so it was
creating the dangling pointer warned about above. When
eventually the m stack was used enough to overwrite the
dangling SEH records, the SEH chain was lost, and any future
panic would not end up in Go's handler.
The bug in TestCallbackPanic and friends was thus creating a
situation where TestSetPanicOnFault - which causes a hardware
fault - would not find the Go fault handler and instead crash
the binary.
Add checks to TestCallbackPanicLocked to diagnose the mistake
in that test instead of leaving a bad state for another test
case to stumble over.
Fix bug by restoring SEH chain during deferred "endcgo"
cleanup.
This bug is likely present in Go 1.2.1, but since it depends
on Go calling C calling Go, with the inner Go panicking and
the outer Go recovering the panic, it seems not important
enough to bother fixing before Go 1.3. Certainly no one has
complained.
Fixes#7470.
LGTM=alex.brainman
R=golang-codereviews, alex.brainman
CC=golang-codereviews, iant, khr
https://golang.org/cl/71440043
Regenerate z-files for DragonFly BSD 3.6.
F_DUP_FD_CLOEXEC is now supported, so remove the zero value constant
from types_dragonfly.go so that we use the generated value from the
z-files.
LGTM=mikioh.mikioh
R=golang-codereviews, mikioh.mikioh
CC=golang-codereviews
https://golang.org/cl/70080047
The format of the DragonFly BSD syscalls.master file has changed
slightly - update mksysnum_dragonfly.pl to match.
LGTM=mikioh.mikioh
R=golang-codereviews, mikioh.mikioh
CC=golang-codereviews
https://golang.org/cl/71460044
Disable the "udp" to IPv6 unicast address on the loopback interface
test under DragonFly BSD. This currently returns a local address of
0.0.0.1, rather than an IPv6 address with zone identifier.
Update #7473
LGTM=mikioh.mikioh
R=golang-codereviews, mikioh.mikioh
CC=golang-codereviews
https://golang.org/cl/71500044
Performing multiple connect system calls on a non-blocking socket
under DragonFly BSD does not necessarily result in errors from earlier
connect calls being returned, particularly if we are connecting to
localhost. Instead, once netpoll tells us that the socket is ready,
get the SO_ERROR socket option to see if the connection succeeded
or failed.
Fixes#7474
LGTM=mikioh.mikioh
R=mikioh.mikioh
CC=golang-codereviews
https://golang.org/cl/69340044
Added test cases and expanded test harness to handle token end
positions.
Also: Make sure token end positions are never outside the valid
position range, as was possible in case of parse errors.
Fixes#7458.
LGTM=bradfitz
R=bradfitz
CC=golang-codereviews
https://golang.org/cl/70190046
the crypto/tls revision d3d43f270632 (CL 67010043, requiring ServerName or InsecureSkipVerify) breaks net/smtp,
since it seems impossible to do SMTP via TLS anymore. i've tried to fix this by simply using a tls.Config with
ServerName, instead of a nil *tls.Config. without this fix, doing SMTP with TLS results in error "tls: either
ServerName or InsecureSkipVerify must be specified in the tls.Config".
testing: the new method TestTlsClient(...) sets up a skeletal smtp server with tls capability, and test client
injects a "fake" certificate allowing tls to work on localhost; thus, the modification to SendMail(...) enabling
this.
Fixes#7437.
LGTM=bradfitz
R=golang-codereviews, josharian, bradfitz
CC=golang-codereviews
https://golang.org/cl/70380043