Extract "cgo -dynimport" and "ld -r" logic into separate helper
methods to make (*builder).cgo somewhat more manageable.

Fixes #16650.

Change-Id: I3e4d77ff3791528b1233467060d3ea83cb854acb
Reviewed-on: https://go-review.googlesource.com/27270
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>

Prior to this CL, cmd/go invoked cmd/asm once
for every assembly file.
The exec and cmd/asm startup overhead dwarfed
the actual time spent assembling.
This CL adds support to cmd/asm to process
multiple input files and uses it in cmd/go.

This cuts 10% off the wall time for 'go build -a math'.

Fixes #15680

Change-Id: I12d2ee2c817207954961dc8f37b8f2b09f835550
Reviewed-on: https://go-review.googlesource.com/27636
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Rob Pike <r@golang.org>

This increases the effectiveness of the
"integer-in-range" CL that follows.

Change-Id: I23b7b6809f0b2c25ed1d59dd2d5429c30f1db89c
Reviewed-on: https://go-review.googlesource.com/27651
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>

The enumerations didn't include the syntactic form where the lhs is
full variable declaration with type specification, as in:

var x, ok T = ...

Fixes #15782.

Change-Id: I0f7bafc37dc9dcf62cdb0894a0d157074ccd4b3e
Reviewed-on: https://go-review.googlesource.com/27670Reviewed-by: Matthew Dempsky <mdempsky@google.com>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Reviewed-by: Rob Pike <r@golang.org>

Functionality is present in bimport.go in slightly modified form.

Change-Id: I6be79d91588873e6ba70d6ab07ba2caa12346dfc
Reviewed-on: https://go-review.googlesource.com/27672Reviewed-by: Matthew Dempsky <mdempsky@google.com>

Update goobj reader so it can provide all the information
necessary to disassemble .o (and .a) files.

Grab architecture of .o files from header.

.o files have relocations in them.  This CL also contains a simple
mechanism to disassemble relocations and add relocation info as an extra
column in the output.

Fixes #13862

Change-Id: I608fd253ff1522ea47f18be650b38d528dae9054
Reviewed-on: https://go-review.googlesource.com/24818Reviewed-by: Ian Lance Taylor <iant@golang.org>
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>

The net package sets a finalizer on *netFD. I looked through all the
uses of *netFD in the package, looking for each case where a *netFD
was passed as an argument and the final reference to the argument was
not a function or method call. I added a call to runtime.KeepAlive after
each such final reference (there were only three).

The code is safe today without the KeepAlive calls because the compiler
keeps arguments alive for the duration of the function. However, that is
not a language requirement, so adding the KeepAlive calls ensures that
this code remains safe even if the compiler changes in the future.

Change-Id: I4e2bd7c5a946035dc509ccefb4828f72335a9ee3
Reviewed-on: https://go-review.googlesource.com/27650
Run-TryBot: Ian Lance Taylor <iant@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>

The os package sets a finalizer on *Process. I looked through all the
uses of *Process in the package, looking for each case where a *Process
was passed as an argument and the final reference to the argument was
not a function or method call. I added a call to runtime.KeepAlive after
each such final reference (there were only three).

The code is safe today without the KeepAlive calls because the compiler
keeps arguments alive for the duration of the function. However, that is
not a language requirement, so adding the KeepAlive calls ensures that
this code remains safe even if the compiler changes in the future.

I also removed an existing unnecessry call to runtime.KeepAlive. The
syscall.Syscall function is handled specially by the compiler to keep
its arguments alive.

Change-Id: Ibd2ff20b31ed3de4f6a59dd1633c1b44001d91d9
Reviewed-on: https://go-review.googlesource.com/27637
Run-TryBot: Ian Lance Taylor <iant@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>

Change-Id: If6e12ebc41152bc0534d3d383df80e960efe97f0
Reviewed-on: https://go-review.googlesource.com/27577Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Reviewed-by: Alex Brainman <alex.brainman@gmail.com>
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>

Change-Id: I7d58d200f7e8b2c0a6e35371da0dafd9b44e9057
Reviewed-on: https://go-review.googlesource.com/26757
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
Reviewed-by: David Crawshaw <crawshaw@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>

Passes toolstash -cmp.

Change-Id: I5b893b8b82b358534fd85542f05e3aa7e666bcd3
Reviewed-on: https://go-review.googlesource.com/26752
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: David Crawshaw <crawshaw@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>

Passes toolstash -cmp.

Change-Id: I2c204ec14b0a72b592fb336acdd4dff55650f7f6
Reviewed-on: https://go-review.googlesource.com/26751Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>

Passes toolstash -cmp.

Change-Id: I16ec0c11096bf4c020cf41392effeb67436f32ba
Reviewed-on: https://go-review.googlesource.com/26750
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>

syscall, internal/syscall/windows, internal/syscall/windows/registry: make go generate work on every os

Fixes #16368

Change-Id: I2ef7a2deb5798e11cc1d3f8ca29a6e1655155422
Reviewed-on: https://go-review.googlesource.com/27411Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>

Updates golang_org/x/net/route to rev 4d38db7 for:
- route: don't crash or hang up with corrupted messages

Change-Id: I22492f56a5e211b5a0479f1e07ad8f42f7b9ea03
Reviewed-on: https://go-review.googlesource.com/27574
Run-TryBot: Mikio Hara <mikioh.mikioh@gmail.com>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>

Updates the behavior of `go get` to return exit status 0 when a
requested package only contains test files.

Fixes #15093

Change-Id: I76b80517d58748090f5e8c6f41178361e2d7ca54
Reviewed-on: https://go-review.googlesource.com/23314Reviewed-by: Ian Lance Taylor <iant@golang.org>
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>

Now that we have ops that can return 2 results, have BSF return a result
and flags.  We can then get rid of the redundant comparison and use CMOV
instead of CMOVconst ops.

Get rid of a bunch of the ops we don't use.  Ctz{8,16}, plus all the Clzs,
and CMOVNEs.  I don't think we'll ever use them, and they would be easy
to add back if needed.

Change-Id: I8858a1d017903474ea7e4002fc76a6a86e7bd487
Reviewed-on: https://go-review.googlesource.com/27630
Run-TryBot: Keith Randall <khr@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: David Chase <drchase@google.com>

Blank struct fields are regular unexported fields. Two
blank fields are different if they are from different
packages. In order to correctly differentiate them, the
compiler needs the package information. Add it to the
export data.

Fixes #15514.

Change-Id: I421aaca22b542fcd0d66b2d2db777249cad78df6
Reviewed-on: https://go-review.googlesource.com/27639Reviewed-by: Matthew Dempsky <mdempsky@google.com>

Towards a fix for #15514.

Change-Id: I62073e9fdcfe5ddda9b0a47fe8554b524191a77c
Reviewed-on: https://go-review.googlesource.com/27638Reviewed-by: Matthew Dempsky <mdempsky@google.com>

The only previous mention of this property was in the String() method.
Since this is the only way to uniquely identify a type and we can't
change this property without breaking the Go 1 guarantee, it seems
better to document this property than hiding it on a method.

Fixes #16348

Change-Id: I3d25f7d6e6007e3c15c2e13010869888d0181fc2
Reviewed-on: https://go-review.googlesource.com/27170Reviewed-by: Ian Lance Taylor <iant@golang.org>

Update #16694.

Change-Id: Id6be1535d8a146b3dac3bee429ce407a51272032
Reviewed-on: https://go-review.googlesource.com/27634
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Rob Pike <r@golang.org>

Change-Id: I4faf9a55414e217f0c48528efb13ab8fdcd9bb16
Reviewed-on: https://go-review.googlesource.com/24845Reviewed-by: Ian Lance Taylor <iant@golang.org>
Run-TryBot: Ian Lance Taylor <iant@golang.org>

Whoever Marvin is, we're one step closer to realizing his dream.

Change-Id: I8dece4417d0f9ec234be158d0ee7bc6735342d93
Reviewed-on: https://go-review.googlesource.com/27465
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>

Minor update on https://go-review.googlesource.com/27441 .

Change-Id: I605a8bfbe67e259020aa53f1d2357808197d02b6
Reviewed-on: https://go-review.googlesource.com/27631Reviewed-by: Matthew Dempsky <mdempsky@google.com>

Add a type conversion to uintptr for untyped constants
before the conversion to unsafe.Pointer.

Fixes #16317

Change-Id: Ib85feccad1019e687e7eb6135890b64b82fb87fb
Reviewed-on: https://go-review.googlesource.com/27441Reviewed-by: Matthew Dempsky <mdempsky@google.com>
Reviewed-by: Robert Griesemer <gri@golang.org>
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>

Some FmtSharp export formatting flag support was removed with
commit b4e9f704. Don't panic if FmtSharp is set, just ignore it.

Fixes #16820.

Change-Id: Ie0c3d3774bd55002f6d2781b1212d070f083e6b2
Reviewed-on: https://go-review.googlesource.com/27556Reviewed-by: Matthew Dempsky <mdempsky@google.com>

If a program wants to evaluate math.Sqrt for any constant value
(for example, math.Sqrt(3)), we can replace that expression with
its evaluation (1.7320508075688772) at compile time, instead of
generating a SQRT assembly command or equivalent.

Adds tests that math.Sqrt generates the correct values. I also
compiled a short program and verified that the Sqrt expression was
replaced by a constant value in the "after opt" step.

Adds a short doc to the top of generic.rules explaining what the file
does and how other files interact with it.

Fixes #15543.

Change-Id: I6b6e63ac61cec50763a09ba581024adeee03d4fa
Reviewed-on: https://go-review.googlesource.com/27457Reviewed-by: Josh Bleecher Snyder <josharian@gmail.com>
Reviewed-by: Keith Randall <khr@golang.org>

Tell msan that the arguments to the traceback functions are initialized,
in case the traceback functions are compiled with -fsanitize=memory.

Change-Id: I3ab0816604906c6cd7086245e6ae2e7fa62fe354
Reviewed-on: https://go-review.googlesource.com/24856
Run-TryBot: Ian Lance Taylor <iant@golang.org>
Reviewed-by: Dmitry Vyukov <dvyukov@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>

I've also unexported a few symbols that weren't used outside the
package.

Updates #16818

Change-Id: I39d9d87b3eec30b88b4a17c1333cfbbfa6b3518f
Reviewed-on: https://go-review.googlesource.com/27468
Run-TryBot: Michael Matloob <matloob@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: David Crawshaw <crawshaw@golang.org>

Otherwise flag.PrintDefaults will fail when it tries to determine
whether the default is the zero value.

Fixes #16694.

Change-Id: I253fbf11ffc0a9069fd48c2c3cf3074df53e3a03
Reviewed-on: https://go-review.googlesource.com/27003
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>

The optional fractional seconds overrides any range error
from the second parsing. Instead don't look for optional fractional
seconds if a range error has occured.

Change-Id: I27e0a2432740f6753668bd8833e48b9495bc4036
Reviewed-on: https://go-review.googlesource.com/27590
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>

Cleanup test code for symbolic links.

Change-Id: I25f561cd34dc4d120a4143f933619d233a6cffc5
Reviewed-on: https://go-review.googlesource.com/27573Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>

Cleanup test code for symbolic links.

Change-Id: I7a116e4d5c0e955578eca53c1af559e9092f60cd
Reviewed-on: https://go-review.googlesource.com/27572Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>

Change-Id: I384eac632a4a87c12977e56a7d7bad7614305c51
Reviewed-on: https://go-review.googlesource.com/25143
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>

Fixes #16802.

Change-Id: I41be7bb4e21e3beaa2136ee69771b0f455b2a7c6
Reviewed-on: https://go-review.googlesource.com/27417Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>

On some error when using io.Copy with TCPConn, it displays an error
correlation like the following:

read tcp 192.0.2.1:1111->192.0.2.2:2222: read tcp [2001:db8::2]:2222->[2001:db8::3]:3333 read: connection reset by peer

the correlation "some error on reading after reading operation" looks a
bit confusing because the operation on the ReadFrom method of TCPConn is
actually "writing after reading." To clarify and avoid confusion, this
change sets "readfrom" to the Op field of outer-most OpError instead of
"read."

Change-Id: I6bf4e2e7247143fa54bbcf9cef7a8ae1ede1b35c
Reviewed-on: https://go-review.googlesource.com/25220Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>

Change-Id: I43f14cdd9eb4a1d5471fc88c1b4759ceb2c674cf
Reviewed-on: https://go-review.googlesource.com/24817
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>

Change-Id: Iabb25e97714d070c31c657559a97a3bfc979da18
Reviewed-on: https://go-review.googlesource.com/25403Reviewed-by: Dmitry Vyukov <dvyukov@google.com>
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>

Change-Id: I7c809ec385b56ebb2ec784a1479d466df6ab4d1a
Reviewed-on: https://go-review.googlesource.com/27565Reviewed-by: Ian Lance Taylor <iant@golang.org>

This enables better packing when key and value
types have different alignments.

Cuts 57k off cmd/go.

Change-Id: Ifdd125264caccd7852d622382c94e4689e757978
Reviewed-on: https://go-review.googlesource.com/26669
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: David Crawshaw <crawshaw@golang.org>