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Commit Graph

24307 Commits

Author SHA1 Message Date
Ian Lance Taylor
f35868a49a cmd/go: don't run TestInstalls in short mode
It changes GOROOT, so we shouldn't run it in short mode.  Also, it's
fairly slow.

Update #11779.

Change-Id: I3d3344954cf9b2ac70070c878a67cb65ac8fd85c
Reviewed-on: https://go-review.googlesource.com/12364
Run-TryBot: Ian Lance Taylor <iant@golang.org>
Reviewed-by: Andrew Gerrand <adg@golang.org>
2015-07-20 03:27:22 +00:00
Ian Lance Taylor
f7e7719f65 cmd/go: rewrite TestNoteReading to use test harness
On my laptop reduces time required for test from 22 seconds to 0.14
seconds.

Update #11779.

Change-Id: I715d85bd9c6f7683c6915eedd2539813aa5efc58
Reviewed-on: https://go-review.googlesource.com/12363
Reviewed-by: David Crawshaw <crawshaw@golang.org>
Reviewed-by: Andrew Gerrand <adg@golang.org>
2015-07-20 03:25:18 +00:00
Michael Hudson-Doyle
1125cd4997 cmd/compile: define func value symbols at declaration
This is mostly Russ's https://golang.org/cl/12145 but with some extra fixes to
account for the fact that function declarations without implementations now
break shared libraries, and including my test case.

Fixes #11480.

Change-Id: Iabdc2934a0378e5025e4e7affadb535eaef2c8f1
Reviewed-on: https://go-review.googlesource.com/12340
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2015-07-20 00:50:46 +00:00
Brad Fitzpatrick
4db074639c net/http: add example for setting trailers in an Handler
Change-Id: I6a8bb853a538c80d95589321d3226784bc017eef
Reviewed-on: https://go-review.googlesource.com/12327
Reviewed-by: Andrew Gerrand <adg@golang.org>
2015-07-20 00:40:40 +00:00
Austin Clements
1942e3814b runtime: clarify runtime.GC blocking behavior
The runtime.GC documentation was rewritten in df2809f to make it clear
that it blocks until GC is complete, but the re-rewrite in ed9a4c9 and
e28a679 lost this property when clarifying that it may also block the
entire program and not just the caller.

Try to arrive at wording that conveys both of these properties.

Change-Id: I1e255322aa28a21a548556ecf2a44d8d8ac524ef
Reviewed-on: https://go-review.googlesource.com/12392
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Reviewed-by: Rob Pike <r@golang.org>
2015-07-19 15:10:06 +00:00
Ian Lance Taylor
692054e76e runtime: check for findmoduledatap returning nil
The findmoduledatap function will not return nil in ordinary use, but
check for nil to try to avoid crashing when we are already crashing.

Update #11783.

Change-Id: If7b1adb51efab13b4c1a37b6f3c9ad22641a0b56
Reviewed-on: https://go-review.googlesource.com/12391
Run-TryBot: Ian Lance Taylor <iant@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
2015-07-18 21:26:59 +00:00
Dmitry Vyukov
e1ee31400a internal/trace: fix fuzzer crashers
Fixes #11766
Fixes #11769
Fixes #11767
Fixes #11770

Change-Id: I441382af58f60deb46dcdd70076763b2c47738d4
Reviewed-on: https://go-review.googlesource.com/12378
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Run-TryBot: Dmitry Vyukov <dvyukov@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2015-07-18 19:51:50 +00:00
Silvan Jegen
c4bfd2de20 bufio: Remove unneeded error initialization
The default value for error is nil so there is no need to assign this
value here.

Change-Id: I4714ef7607996ccbf91b704390e1d1d39ee3847b
Reviewed-on: https://go-review.googlesource.com/12355
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2015-07-18 18:05:23 +00:00
Ian Lance Taylor
dabb268170 cmd/compile: ignore carriage return in magic comments
Update #11771.

Change-Id: I3bb3262619765d3ca79652817e17e8f260f41907
Reviewed-on: https://go-review.googlesource.com/12379
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
2015-07-18 17:33:53 +00:00
Mikio Hara
aadd84e0c4 net: classify site-local unicast in address selection
This change adds site-local unicast classification for users still using
the deprecated addresses internally.

Change-Id: If50870c6d4a85fe471c002b161eec59efcebe2f4
Reviewed-on: https://go-review.googlesource.com/12344
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
2015-07-18 01:35:25 +00:00
Brad Fitzpatrick
90c668d1af os: remove stuttering return value names
Old style. Make it compliant with our code review comments document.

Also, make WriteString's return parameter named 'n', not 'ret', for
consistency.

Noticed during another documentation review.

Change-Id: Ie88910c5841f8353bc5c0152e2168b497578e15e
Reviewed-on: https://go-review.googlesource.com/12324
Reviewed-by: Rob Pike <r@golang.org>
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2015-07-18 01:34:21 +00:00
Alex Brainman
4a0d9587f2 runtime: skip TestReturnAfterStackGrowInCallback if gcc is not found
Fixes #11754

Change-Id: Ifa423ca6eea46d1500278db290498724a9559d14
Reviewed-on: https://go-review.googlesource.com/12347
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
2015-07-18 01:29:09 +00:00
Brad Fitzpatrick
60315002f3 doc: document GODEBUG=netdns=X and netcgo in go1.5.txt
Change-Id: I720aeb1511e407750617e23c4cba1edcddf745bb
Reviewed-on: https://go-review.googlesource.com/12326
Reviewed-by: Rob Pike <r@golang.org>
2015-07-18 01:00:55 +00:00
Rob Pike
e28a679216 runtime: make the GC message less committal.
We shouldn't guarantee this behavior, but suggest it's possible.

Change-Id: I4c2afb48b99be4d91537306d3337171a13c9990a
Reviewed-on: https://go-review.googlesource.com/12346
Reviewed-by: David Crawshaw <crawshaw@golang.org>
2015-07-18 00:28:50 +00:00
Ian Lance Taylor
c4f18d5374 cmd/go: ignore import of "C" when fetching dependencies
The change https://golang.org/cl/12192 changed the get code to use the
list of package imports, not the computed list of dependencies, as the
computed list could be out of date if the package changed when using
go get -u.  Computing the dependency list would skip an import of "C",
but that would still be on the package import list.  This changes the
code to skip "C" when walking the import list.

No test--the best test would be to add an import of "C" to
github.com/rsc/go-get-issue-9224-cmd for TestGoGetUpdate.

Fixes #11738.

Change-Id: Id89ddafeade2391d15688bfd142fafd67844a941
Reviewed-on: https://go-review.googlesource.com/12322
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Andrew Gerrand <adg@golang.org>
2015-07-17 22:58:39 +00:00
Dave Cheney
955c0fd2f9 os: add test to ensure Rename returns *LinkError
Updates #10061

CL 12353 updated the documentation for os.Rename to stipulate the function will
return errors of type *os.LinkError. This CL adds a test to ensure that the
implementations continue to obey this contract.

Change-Id: I41beb8c9d8356c737de251fdc6f652caab3ee636
Reviewed-on: https://go-review.googlesource.com/12329
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2015-07-17 22:46:05 +00:00
Rob Pike
ed9a4c91c2 runtime: document that GC blocks the whole program
No code changes. Just make it clear that runtime.GC is not concurrent.

Change-Id: I00a99ebd26402817c665c9a128978cef19f037be
Reviewed-on: https://go-review.googlesource.com/12345
Reviewed-by: Dave Cheney <dave@cheney.net>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2015-07-17 22:40:21 +00:00
Paolo Martini
3549178e55 doc: fix typo
The document `doc/go_spec.html` uses "preceeding" instead of the word
"preceding" in one place.

Fixed another occurrence in `src/go/types/typexpr.go`.

Change-Id: Ic67f62026b5c9d002c5c5632299f14ecac8b02ae
Reviewed-on: https://go-review.googlesource.com/12354
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2015-07-17 22:33:51 +00:00
Hyang-Ah (Hana) Kim
a81c656352 androidtest.bash: robust cleanup in case of failure.
Change-Id: I69ed001bca4987e08b46a8288f6feae2aca6a142
Reviewed-on: https://go-review.googlesource.com/12380
Reviewed-by: David Crawshaw <crawshaw@golang.org>
2015-07-17 21:12:12 +00:00
David Crawshaw
ebb67836f9 doc: document ios build tag for crypto/x509
Change-Id: I6e6d38ae347b4f5a33dff609b89785a038bc384c
Reviewed-on: https://go-review.googlesource.com/12304
Reviewed-by: Andrew Gerrand <adg@golang.org>
2015-07-17 17:58:16 +00:00
Austin Clements
e33d6b3d4d runtime: remove out-of-date comment
An out-of-date comment snuck in to cc8f544. Remove it.

Change-Id: I5bc7c17e737d1cabe57b88de06d7579c60ca28ff
Reviewed-on: https://go-review.googlesource.com/12328
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
2015-07-17 16:52:32 +00:00
Jeff R. Allen
fb90f4c1c2 os: improve documentation on Rename
Rename should document that it returns *LinkError,
like Create and Stat do.

Fixes #10061

Change-Id: I7bfe8b0267f6c4a57dd6b26cba44928714711724
Reviewed-on: https://go-review.googlesource.com/12353
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
2015-07-17 15:07:39 +00:00
Mikio Hara
2899be8120 net: avoid unnecessary conversion in address selection
Change-Id: I0d940810b493249bc092cd38bdb434f7fa67cafb
Reviewed-on: https://go-review.googlesource.com/12341
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Run-TryBot: Mikio Hara <mikioh.mikioh@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2015-07-17 08:33:03 +00:00
Austin Clements
cc8f544198 runtime: don't free large spans until heapBitsSweepSpan returns
This fixes a race between 1) sweeping and freeing an unmarked large
span and 2) reusing that span and allocating from it. This race arises
because mSpan_Sweep returns spans for large objects to the heap
*before* heapBitsSweepSpan clears the mark bit on the object in the
span.

Specifically, the following sequence of events can lead to an
incorrectly zeroed bitmap byte, which causes the garbage collector to
not trace any pointers in that object (the pointer bits for the first
four words are cleared, and the scan bits are also cleared, so it
looks like a no-scan object).

1) P0 calls mSpan_Sweep on a large span S0 with an unmarked object on it.

2) mSpan_Sweep calls heapBitsSweepSpan, which invokes the callback for
   the one (unmarked) object on the span.

3) The callback calls mHeap_Free, which makes span S0 available for
   allocation, but this is too early.

4) P1 grabs this S0 from the heap to use for allocation.

5) P1 allocates an object on this span and writes that object's type
   bits to the bitmap.

6) P0 returns from the callback to heapBitsSweepSpan.
   heapBitsSweepSpan clears the byte containing the mark, even though
   this span is now owned by P1 and this byte contains important
   bitmap information.

This fixes this problem by simply delaying the mHeap_Free until after
the heapBitsSweepSpan. I think the overall logic of mSpan_Sweep could
be simplified now, but this seems like the minimal change.

Fixes #11617.

Change-Id: I6b1382c7e7cc35f81984467c0772fe9848b7522a
Reviewed-on: https://go-review.googlesource.com/12320
Run-TryBot: Austin Clements <austin@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
Reviewed-by: Rob Pike <r@golang.org>
2015-07-17 03:34:11 +00:00
Rob Pike
5c62e5f9da cmd/fix: add gotypes module
Adjusts for the move from golang.org/x/tools/go/types and .../go/exact
to go/types and go/constant in the main repository.

Change-Id: I0da7248c540939e3e9b09c915b0a296937f1be73
Reviewed-on: https://go-review.googlesource.com/12284
Reviewed-by: Andrew Gerrand <adg@golang.org>
2015-07-17 01:47:14 +00:00
Mikio Hara
29ffa4bd92 cmd/go: don't put mycmd in wrong directory
Change-Id: Ia7cc1d52211b32a2eb2b3888d621b28d6932aca9
Reviewed-on: https://go-review.googlesource.com/12290
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2015-07-17 01:28:16 +00:00
Carlos C
9f70cd8223 net/mail: add example to package
Change-Id: I912cafc66463f81cde839afc8f06b7eadcbf6f57
Reviewed-on: https://go-review.googlesource.com/11992
Reviewed-by: Andrew Gerrand <adg@golang.org>
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
2015-07-16 22:34:35 +00:00
Brad Fitzpatrick
f04c506917 A+C: more updates
Update #10639

Change-Id: I2d7817ac0aefb5dd2569d7e83afbc51851e24b42
Reviewed-on: https://go-review.googlesource.com/12321
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
2015-07-16 22:03:55 +00:00
Brad Fitzpatrick
adb1e03013 net: RFC 6724 address selection
At least the most important parts, I think.

Fixes #10552

Change-Id: I1a03c5405bdbef337e0245d226e9247d3d067393
Reviewed-on: https://go-review.googlesource.com/12246
Reviewed-by: Andrew Gerrand <adg@golang.org>
Reviewed-by: Russ Cox <rsc@golang.org>
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
2015-07-16 20:56:23 +00:00
David Crawshaw
29eb7d18ed crypto/x509: iOS build tag
The iOS simulator compiles with GOOS=darwin GOARCH=386, and x509
sets the inappropriate flag -mmacosx-version-min=10.6. Condition
its compilation on the absence of an "ios" build tag.

Fixes #11736.

Change-Id: I4aa230643347320c3cb9d03b972734b2e0db930e
Reviewed-on: https://go-review.googlesource.com/12301
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
2015-07-16 19:10:11 +00:00
Carlos C
6094b88c48 net/url: add example to URL.ResolveReference
Change-Id: I9db1997b8dc7e06e9d124753ead6221470a1edf9
Reviewed-on: https://go-review.googlesource.com/12254
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
2015-07-16 16:18:18 +00:00
Rob Pike
6163cf87c8 doc: describe tracing, mention go fix
Also add a link to a couple of the talks from GopherCon 2015.

Change-Id: I11e1c550e999553163d3fb5e900f167c849ce33f
Reviewed-on: https://go-review.googlesource.com/12287
Reviewed-by: Andrew Gerrand <adg@golang.org>
2015-07-16 05:35:22 +00:00
Rob Pike
b0834b5ea2 flag: add comment stating that Set is called in sequence across the command line
No code changes.

Change-Id: I3b78b1048318a4b80747fde8cab919282fc444a8
Reviewed-on: https://go-review.googlesource.com/12285
Reviewed-by: Andrew Gerrand <adg@golang.org>
2015-07-16 05:33:47 +00:00
Russ Cox
19916e453e test/fixedbugs: disable issue11656.go on arm64
For #11656.

Change-Id: I8365d33a15419bd0e54f71182ad0994e41650264
Reviewed-on: https://go-review.googlesource.com/12248
Reviewed-by: Russ Cox <rsc@golang.org>
2015-07-16 02:16:20 +00:00
Russ Cox
a93e5b4ff9 Revert "runtime: diagnose invalid pointers during GC"
Broke arm64. Update #9880.

This reverts commit 38d9b2a3a9.

Change-Id: I35fa21005af2183828a9d8b195ebcfbe45ec5138
Reviewed-on: https://go-review.googlesource.com/12247
Reviewed-by: Russ Cox <rsc@golang.org>
2015-07-16 01:49:58 +00:00
Nigel Tao
816222d10f image/color: fix format typo in the tests.
Change-Id: I6f79d201aa4e8c0e3be8d965f14ed36518536036
Reviewed-on: https://go-review.googlesource.com/12281
Reviewed-by: Rob Pike <r@golang.org>
2015-07-16 01:41:34 +00:00
Chris Broadfoot
2072fc3061 A+C: Add missing entries, full names.
Updates #10639

Change-Id: Ifece75b8d1d822869df8abf654725a00bef4fc25
Reviewed-on: https://go-review.googlesource.com/12280
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
2015-07-16 00:57:45 +00:00
Russ Cox
08dbd8ae6d Revert "cmd/internal/obj: fix pc/sp information for prologue"
This seems to have broken arm64 in a mysterious way. Will try again later.

This reverts commit 0a3c991fd3.

Change-Id: Ic1b53413c4168977a27381d9cc6fb8d9d7cbb780
Reviewed-on: https://go-review.googlesource.com/12245
Reviewed-by: Russ Cox <rsc@golang.org>
2015-07-15 23:28:42 +00:00
Brad Fitzpatrick
88fc3587ec net/http: don't reuse conns after incomplete 100-continue requests
If we receive an HTTP request with "Expect: 100-continue" and the
Handler never read to EOF, the conn is in an unknown state.
Don't reuse that connection.

Fixes #11549

Change-Id: I5be93e7a54e899d615b05f72bdcf12b25304bc60
Reviewed-on: https://go-review.googlesource.com/12262
Reviewed-by: Andrew Gerrand <adg@golang.org>
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
2015-07-15 23:06:23 +00:00
Brad Fitzpatrick
2b9e5a7165 A+C: more updates, including Medium corporate CLA
Updates #10639

Change-Id: I0958e150f6eab122095bfc148746a38028b72dbc
Reviewed-on: https://go-review.googlesource.com/12263
Reviewed-by: Andrew Gerrand <adg@golang.org>
2015-07-15 21:49:36 +00:00
Andrew Gerrand
5cd2944803 cmd/go: fix parsing of Git SCP-like remotes
Now that we care about the protocol of Git remotes (for the -insecure
flag), we need to recognize and parse the SCP-like remote format.

Fixes golang/go#11457

Change-Id: Ia26132274fafb1cbfefe2475f7ac5f17ccd6da40
Reviewed-on: https://go-review.googlesource.com/12226
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2015-07-15 21:33:57 +00:00
Austin Clements
e42413cecc runtime: fix saved PC/SP after safe-point function in syscall
Running a safe-point function on syscall entry uses systemstack() and
hence clobbers g.sched.pc and g.sched.sp. Fix this by re-saving them
after the systemstack, just like in the other uses of systemstack in
reentersyscall.

Change-Id: I47868a53eba24d81919fda56ef6bbcf72f1f922e
Reviewed-on: https://go-review.googlesource.com/12125
Reviewed-by: Russ Cox <rsc@golang.org>
2015-07-15 21:09:16 +00:00
Austin Clements
edfc979725 runtime: run safe-point function before entering _Psyscall
Currently, we run a P's safe-point function immediately after entering
_Psyscall state. This is unsafe, since as soon as we put the P in
_Psyscall, we no longer control the P and another M may claim it.
We'll still run the safe-point function only once (because doing so
races on an atomic), but the P may no longer be at a safe-point when
we do so.

In particular, this means that the use of forEachP to dispose all P's
gcw caches is unsafe. A P may enter a syscall, run the safe-point
function, and dispose the P's gcw cache concurrently with another M
claiming the P and attempting to use its gcw cache. If this happens,
we may empty the gcw's workbuf after putting it on
work.{full,partial}, or add pointers to it after putting it in
work.empty. This will cause an assertion failure when we later pop the
workbuf from the list and its object count is inconsistent with the
list we got it from.

Fix this by running the safe-point function just before putting the P
in _Psyscall.

Related to #11640. This probably fixes this issue, but while I'm able
to show that we can enter a bad safe-point state as a result of this,
I can't reproduce that specific failure.

Change-Id: I6989c8ca7ef2a4a941ae1931e9a0748cbbb59434
Reviewed-on: https://go-review.googlesource.com/12124
Run-TryBot: Austin Clements <austin@google.com>
Reviewed-by: Russ Cox <rsc@golang.org>
2015-07-15 21:09:07 +00:00
Matthew Dempsky
64e53337af runtime: fix go:nowritebarrier annotation on gcmarkwb_m
Change-Id: I945d46d3bb63f1992bce0d0b1e89e75cac9bbd54
Reviewed-on: https://go-review.googlesource.com/12271
Reviewed-by: Austin Clements <austin@google.com>
Run-TryBot: Austin Clements <austin@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2015-07-15 21:06:13 +00:00
Ian Lance Taylor
2e4b659954 cmd/compile: recognize embedded field in inlined function
There was already special code to recognize "?" in hidden_structdcl,
which is used for inlined types and variables.  This recognizes "?" in
structdcl as well, a case that arises when a struct type appears
within an inlined function body.

Fixes #10219.

Change-Id: Ic5257ae54f817e0d4a189c2294dcd633c9f2101a
Reviewed-on: https://go-review.googlesource.com/12241
Run-TryBot: Ian Lance Taylor <iant@golang.org>
Reviewed-by: Russ Cox <rsc@golang.org>
2015-07-15 06:04:51 +00:00
Russ Cox
749b391c55 encoding/json: document and test overwrite of slice, map during Unmarshal
Fixes #8837.

Change-Id: Iaaecbb0b324004cb74b16b764126b01315e6a16e
Reviewed-on: https://go-review.googlesource.com/12209
Reviewed-by: Andrew Gerrand <adg@golang.org>
2015-07-15 05:51:02 +00:00
Rob Pike
2d25318f08 asm: fix error messages and comments for "register pair"
The parser treats (R1+R2) on ppc64 the same as (R1,R2) on arm,
but it is not strictly a "register pair". Improve the text.

No semantic change.

Change-Id: Ib8b14881c6467add0d53150a901c01e962afb28b
Reviewed-on: https://go-review.googlesource.com/12212
Reviewed-by: Russ Cox <rsc@golang.org>
2015-07-15 05:45:29 +00:00
Russ Cox
38d9b2a3a9 runtime: diagnose invalid pointers during GC
For #9880. Let's see what breaks.

Change-Id: Ic8b99a604e60177a448af5f7173595feed607875
Reviewed-on: https://go-review.googlesource.com/10818
Reviewed-by: Austin Clements <austin@google.com>
Run-TryBot: Austin Clements <austin@google.com>
2015-07-15 05:42:06 +00:00
Russ Cox
7feb424928 cmd/compile: fix PtrTo(t) for unnamed t with embedded fields
Fixes #8427.

Change-Id: I826a3bc4519845ad30d6dbaf058fe7ed7bee8db0
Reviewed-on: https://go-review.googlesource.com/12233
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2015-07-15 05:36:27 +00:00
Russ Cox
bed6326a3c math: fix Log2 test failures on ppc64 (and s390)
- Make Log2 exact for powers of two.
- Fix error tolerance function to make tolerance
  a function of the correct (expected) value.

Fixes #9066.

Change-Id: I0320a93ce4130deed1c7b7685627d51acb7bc56d
Reviewed-on: https://go-review.googlesource.com/12230
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2015-07-15 05:35:22 +00:00