The -I. syntax now needs a space to be recognized in the
compiler.

R=golang-dev, bradfitz
CC=golang-dev
https://golang.org/cl/7098046

This allows test/dwarf to be supported by run.go.

Update #4139.

R=golang-dev, bradfitz, iant
CC=golang-dev
https://golang.org/cl/7064067

This introduces a buffer between writing from a handler and
writing chunks.  Further, it delays writing the header until
the first full chunk is ready.  In the case where the first
full chunk is also the final chunk (for small responses), that
means we can also compute a Content-Length, which is a nice
side effect for certain benchmarks.

Fixes #2357

R=golang-dev, dave, minux.ma, rsc, adg, balasanjay
CC=golang-dev
https://golang.org/cl/6964043

Update #2656

R=golang-dev, iant, minux.ma, bradfitz
CC=golang-dev
https://golang.org/cl/7065063

The peephole optimizer would keep hands off AX and X0 during returns, even though go doesn't return through registers.

R=dave, rsc
CC=golang-dev
https://golang.org/cl/7030046

Fixes #4583.

R=golang-dev, minux.ma, bradfitz, rsc, dave
CC=golang-dev
https://golang.org/cl/6976050

R=golang-dev, dave, rsc
CC=golang-dev
https://golang.org/cl/7066052

Modeled after CL 7030046 by daniel.morsing.

example program:
func f(x int) int { x -= 10; return x }

5g -S difference:
 --- prog list "f" ---
 0011 (x.go:7) TEXT   	add+0(SB),$0-8
 0012 (x.go:7) MOVW   	x+0(FP),R0
-0013 (x.go:7) SUB    	$10,R0,R2
-0014 (x.go:7) MOVW   	R2,R0
-0015 (x.go:7) MOVW   	R2,.noname+4(FP)
-0016 (x.go:7) RET    	,
+0013 (x.go:7) SUB    	$10,R0
+0014 (x.go:7) MOVW   	R0,.noname+4(FP)
+0015 (x.go:7) RET    	,

R=dave, rsc
CC=golang-dev
https://golang.org/cl/7030047

also added appropriate docs to cmd/ld/doc.go
(largely copied from Russ's CL 6938073).

R=rsc
CC=golang-dev
https://golang.org/cl/7004049

Skip most of the scanning and parsing logic for simple (non-object/array) JSON values.

benchmark                   old ns/op    new ns/op    delta
BenchmarkUnmarshalInt             948          436  -54.01%
BenchmarkUnmarshalUint            930          427  -54.09%
BenchmarkUnmarshalString         1407          715  -49.18%
BenchmarkUnmarshalFloat          1114          536  -51.89%
BenchmarkUnmarshalBool            759          266  -64.95%
BenchmarkUnmarshalStruct         8165         8181   +0.20%

No significant effects on the go1 benchmarks:

benchmark                 old ns/op    new ns/op    delta
BenchmarkBinaryTree17    9647362752   9596196417   -0.53%
BenchmarkFannkuch11      5623613048   5518694872   -1.87%
BenchmarkGobDecode         32944041     33165434   +0.67%
BenchmarkGobEncode         21237482     21080554   -0.74%
BenchmarkGzip             750955920    749861980   -0.15%
BenchmarkGunzip           197369742    197886192   +0.26%
BenchmarkJSONEncode        79274091     78891137   -0.48%
BenchmarkJSONDecode       180257802    175280358   -2.76%
BenchmarkMandelbrot200      7396666      7388266   -0.11%
BenchmarkParse             11446460     11386550   -0.52%
BenchmarkRevcomp         1605152523   1599512029   -0.35%
BenchmarkTemplate         204538247    207765574   +1.58%

benchmark                  old MB/s     new MB/s  speedup
BenchmarkGobDecode            23.30        23.14    0.99x
BenchmarkGobEncode            36.14        36.41    1.01x
BenchmarkGzip                 25.84        25.88    1.00x
BenchmarkGunzip               98.32        98.06    1.00x
BenchmarkJSONEncode           24.48        24.60    1.00x
BenchmarkJSONDecode           10.76        11.07    1.03x
BenchmarkParse                 5.06         5.09    1.01x
BenchmarkRevcomp             158.34       158.90    1.00x
BenchmarkTemplate              9.49         9.34    0.98x

Fixes #3949.

R=golang-dev, dave, bradfitz, timo
CC=golang-dev
https://golang.org/cl/7068043

Update #2631.
Update #3097.

R=golang-dev, bradfitz
CC=golang-dev
https://golang.org/cl/7061060

Fixes #2656.

R=golang-dev, bradfitz, iant, minux.ma
CC=golang-dev
https://golang.org/cl/7062057

5c miscompiles *p++ = struct_literal.

R=dave, golang-dev
CC=golang-dev
https://golang.org/cl/7065069

R=rsc, dvyukov, remyoudompheng, dave, minux.ma, bradfitz
CC=golang-dev
https://golang.org/cl/6945069

Generated by addca.

R=gobot
CC=golang-dev
https://golang.org/cl/7057067

benchmark                      old ns/op    new ns/op    delta
BenchmarkStackGrowth                 665          548  -17.59%
BenchmarkStackGrowth-2               333          274  -17.72%
BenchmarkStackGrowth-4               224          168  -25.00%
BenchmarkStackGrowth-8               124           91  -26.21%
BenchmarkStackGrowth-16               82           70  -14.55%
BenchmarkStackGrowth-32               73           59  -19.49%

R=nigeltao, minux.ma, rsc
CC=golang-dev
https://golang.org/cl/7026044

Introduce global stack segment cache and limit per-thread cache size.
This greatly reduces StackSys memory on workloads that create lots of threads.

benchmark                      old ns/op    new ns/op    delta
BenchmarkStackGrowth                 665          656   -1.35%
BenchmarkStackGrowth-2               333          328   -1.50%
BenchmarkStackGrowth-4               224          172  -23.21%
BenchmarkStackGrowth-8               124           91  -26.13%
BenchmarkStackGrowth-16               82           47  -41.94%
BenchmarkStackGrowth-32               73           40  -44.79%

BenchmarkStackGrowthDeep           97231        94391   -2.92%
BenchmarkStackGrowthDeep-2         47230        58562  +23.99%
BenchmarkStackGrowthDeep-4         24993        49356  +97.48%
BenchmarkStackGrowthDeep-8         15105        30072  +99.09%
BenchmarkStackGrowthDeep-16        10005        15623  +56.15%
BenchmarkStackGrowthDeep-32        12517        13069   +4.41%

TestStackMem#1,MB                  310          12       -96.13%
TestStackMem#2,MB                  296          14       -95.27%
TestStackMem#3,MB                  479          14       -97.08%

TestStackMem#1,sec                 3.22         2.26     -29.81%
TestStackMem#2,sec                 2.43         2.15     -11.52%
TestStackMem#3,sec                 2.50         2.38      -4.80%

R=sougou, no.smile.face, rsc
CC=golang-dev, msolomon
https://golang.org/cl/7029044

Update #4582.

R=nigeltao, dave, adg
CC=golang-dev
https://golang.org/cl/7070065

R=golang-dev, rsc
CC=golang-dev
https://golang.org/cl/7057064

R=golang-dev, dsymonds
CC=golang-dev
https://golang.org/cl/7065067

Changeset f483bfe81114 moved ELF generation to the architecture
independent code and in doing so added a Section* to the Sym
type and an Elf64_Shdr* to the Section type.

This caused the Plan 9 compilers to complain about incompatible
type signatures in the many files that reference the Sym type.

R=rsc, dave
CC=golang-dev
https://golang.org/cl/7057058

Fixes #4186.

Back in the day, before the Go 1.0 release, $GOROOT was mandatory for building from source. Fast forward to now and $GOPATH is mandatory and $GOROOT is optional, and mainly used by those who use the binary distribution in uncommon places.

For example, most novices at least know about `sudo` as they would have used it to install the binary tarball into /usr/local. It is logical they would use the `sudo` hammer to `go get` other Go packages when faced with a permission error talking about the path they just had to use `sudo` on last time.

Even if they had read the documentation and set $GOPATH, go get will not work as expected as `sudo` masks most environment variables.

llucky(~) % ~/go/bin/go env | grep GOPATH
GOPATH="/home/dfc"
lucky(~) % sudo ~/go/bin/go env | grep GOPATH
GOPATH=""

This CL therefore proposes to remove support for using `go get` to download source into $GOROOT.

This CL also proposes an error when GOPATH=$GOROOT, as this is another place where new Go users can get stuck.

Further discussion: https://groups.google.com/d/topic/golang-nuts/VIg3fjHiHRI/discussion

R=rsc, adg, minux.ma
CC=golang-dev
https://golang.org/cl/6941058

R=golang-dev, bradfitz, minux.ma
CC=golang-dev
https://golang.org/cl/7057063

R=dave, golang-dev, rsc
CC=golang-dev
https://golang.org/cl/7068044

The linker split PKGDEF into (prefix, name, def) pairs,
and defines def to begin after a space following the identifier.
This is totally wrong for the following export data:

        func "".FunctionName()
        var SomethingCompletelyUnrelated int

The linker would parse
    name=`"".FunctionName()\n\tvar`
    def=`SomethingCompletelyUnrelated int`
since there is no space after FunctionName.

R=minux.ma, rsc
CC=golang-dev
https://golang.org/cl/7068051

Our source no longer needs these flags set to build cleanly using clang.

Tested with

* Ubuntu clang version 3.0-6ubuntu3 (tags/RELEASE_30/final) (based on LLVM 3.0) on i386
* clang version 3.2 (tags/RELEASE_32/final) on amd64 cross compiling all platforms

R=golang-dev, rsc
CC=golang-dev
https://golang.org/cl/7058053

Fixes #4624.

R=rsc
CC=golang-dev
https://golang.org/cl/7058052

Fixes #4616.

R=rsc
CC=golang-dev
https://golang.org/cl/7069049

Fixes #4612.

R=rsc, iant, ken, r
CC=golang-dev
https://golang.org/cl/7076043

R=golang-dev, iant
CC=golang-dev
https://golang.org/cl/7063056

The old code made it impossible to implement a reverse proxy
with anything less than 4k write granularity to the backends.

R=golang-dev, adg
CC=golang-dev
https://golang.org/cl/7060059

Fixes #4625.

R=iant, adg
CC=golang-dev
https://golang.org/cl/7064052

suggested by pkleiweg.

Fixes #3471.

R=adonovan, pkleiweg, rsc
CC=golang-dev
https://golang.org/cl/7060056

R=adonovan
CC=golang-dev
https://golang.org/cl/7060054

R=golang-dev, minux.ma
CC=golang-dev
https://golang.org/cl/7079043

R=golang-dev, bradfitz
CC=golang-dev
https://golang.org/cl/7061051

Fixes #4367.

R=golang-dev, bradfitz
CC=golang-dev
https://golang.org/cl/7062052

R=golang-dev, dsymonds
CC=golang-dev
https://golang.org/cl/7061050

Generated by addca.

R=gobot
CC=golang-dev
https://golang.org/cl/7064054

The spec talks explicitly about rune literals but the
respective production is still called char_lit for
historic reasons. Updated the two occurences.

Fixes #4602.

R=rsc, iant, r, ken
CC=golang-dev
https://golang.org/cl/7070048