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go/api
Ian Gudger 154860ff17 syscall: remove X__cmsg_data from Cmsghdr
This field is a zero length array and has little use. Since Go 1.5, trailing
zero-length arrays take up space. Both syscall.UnixRights() and
syscall.ParseSocketControlMessage() depend on being able to do an unsafe cast
of socket control message data to Cmsghdr this is only safe if the socket
control message data is greater than or equal to the size of Cmsghdr. Since
control message data that is equal in size to Cmsghdr without X__cmsg_data is
a valid socket control message, we must remove X__cmsg_data or not perform the
unsafe cast.

Removing X__cmsg_data will prevent Go code that uses X__cmsg_data from
compiling, but removing the unsafe cast will cause Go code that uses
X__cmsg_data to fail or exhibit undefined behavior at runtime. It was
therefore decided that removing X__cmsg_data was the better option.

Fixes #17649

Change-Id: I39f323f978eca09d62da5785c5c5c9c7cbdf8c31
Reviewed-on: https://go-review.googlesource.com/32319
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Reviewed-by: Russ Cox <rsc@golang.org>
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2016-10-30 19:04:09 +00:00
..
except.txt syscall: remove X__cmsg_data from Cmsghdr 2016-10-30 19:04:09 +00:00
go1.1.txt go/constant: switch to floating-point representation when fractions become too large 2015-12-14 23:42:01 +00:00
go1.2.txt api: add go1.2.txt, use in tests 2013-10-18 13:36:59 +09:00
go1.3.txt api: add go1.3.txt 2014-06-02 11:45:00 +09:00
go1.4.txt [release-branch.go1.4] api: create go1.4.txt 2014-12-12 14:01:01 +11:00
go1.5.txt api: update go1.5.txt 2015-07-30 21:14:09 +00:00
go1.6.txt go/types: rename Importer2 to ImporterFrom 2016-01-13 23:40:13 +00:00
go1.7.txt unicode: upgrade to version 9.0.0 2016-06-28 15:08:11 +00:00
go1.txt encoding/xml: add, support Marshaler interface 2013-08-14 14:58:28 -04:00
next.txt api: update next.txt 2016-10-26 19:46:59 +00:00
README api: fix typo in README 2015-12-19 07:15:39 +00:00

Files in this directory are data for Go's API checker ("go tool api", in src/cmd/api).

Each file is a list of API features, one per line.

go1.txt (and similarly named files) are frozen once a version has been
shipped. Each file adds new lines but does not remove any.

except.txt lists features that may disappear without breaking true
compatibility.

next.txt is the only file intended to be mutated. It's a list of
features that may be added to the next version. It only affects
warning output from the go api tool.