Commit graph

11 commits

Author SHA1 Message Date
Michael Hudson-Doyle
2c2cbb69c8 cmd/internal/ld: put read-only relocated data into .data.rel.ro when making a shared object
Currently Go produces shared libraries that cannot be shared between processes
because they have relocations against the text segment (not text section). This
fixes this by moving some data to sections with magic names recognized by the
static linker.

Fixes #10914
Updates #9210

Change-Id: I7178daadc0ae87953d5a084aa3d580f4e3b46d47
Reviewed-on: https://go-review.googlesource.com/10300
Run-TryBot: Michael Hudson-Doyle <michael.hudson@canonical.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2015-09-04 05:25:10 +00:00
Michael Hudson-Doyle
9e6ba37b86 cmd/internal/obj: some platform independent bits of proper toolchain support for thread local storage
Also simplifies some silliness around making the .tbss section wrt internal
vs external linking. The "make TLS make sense" project has quite a few more
steps to go.

Issue #11270

Change-Id: Ia4fa135cb22d916728ead95bdbc0ebc1ae06f05c
Reviewed-on: https://go-review.googlesource.com/13990
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Reviewed-by: David Crawshaw <crawshaw@golang.org>
Run-TryBot: David Crawshaw <crawshaw@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2015-09-03 14:06:07 +00:00
Russ Cox
66cb5cd530 cmd/link: increase ELFRESERVE to a full page
Etcd and kubernetes have hit this.
See  https://bugzilla.redhat.com/show_bug.cgi?id=1248071

Change-Id: I6231013efa0a19ee74f7ebacd1024adb368af83a
Reviewed-on: https://go-review.googlesource.com/12951
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2015-07-31 02:18:35 +00:00
Brad Fitzpatrick
2ae77376f7 all: link to https instead of http
The one in misc/makerelease/makerelease.go is particularly bad and
probably warrants rotating our keys.

I didn't update old weekly notes, and reverted some changes involving
test code for now, since we're late in the Go 1.5 freeze. Otherwise,
the rest are all auto-generated changes, and all manually reviewed.

Change-Id: Ia2753576ab5d64826a167d259f48a2f50508792d
Reviewed-on: https://go-review.googlesource.com/12048
Reviewed-by: Rob Pike <r@golang.org>
2015-07-11 14:36:33 +00:00
Russ Cox
34846aef78 cmd/link: fix -s with external linking
This code used to only be run for ELF, with the predictable
result that using -s with external linking broke on Windows and OS X.
Moving it here should fix Windows and does fix OS X.

CL 10835 also claims to fix the crash on Windows.
I don't know whether it does so correctly, but regardless,
this CL should make that one a no-op.

Fixes #10254.

Change-Id: I2e7b45ab0c28568ddbb1b50581dcc157ae0e7ffe
Reviewed-on: https://go-review.googlesource.com/11695
Reviewed-by: David Crawshaw <crawshaw@golang.org>
2015-06-29 19:49:38 +00:00
Russ Cox
ac1f48e2f6 cmd/link: add -buildid flag to write Go build ID to ELF output, same as cmd/compile
Other binary formats to follow.

Using our own note instead of the GNU build ID note because
we are not the GNU project, and I can't guarantee that the semantics
of our note and the semantics of the GNU note will match forever.
(Also they don't match today.)

For #11048.

Change-Id: Iec7e5a2e49d52b6d3a51b0aface2de7c77a45491
Reviewed-on: https://go-review.googlesource.com/10706
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2015-06-05 04:02:26 +00:00
Russ Cox
7e27625e25 cmd/go, cmd/link: use "Go" not "GO" as ELF note identifier
Change-Id: I038e892725836ab7718f7638e8ad5712953f2cb5
Reviewed-on: https://go-review.googlesource.com/10704
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2015-06-05 03:59:46 +00:00
Michael Hudson-Doyle
bcc1870fcf cmd/internal/ld: store the libraries a shared library was linked against in a note
The motivation for this is the innocuous looking test case that is added. This
creates a stack exe -> libdep2.so -> libdep.so -> libruntime.so. The problem
comes from the fact that a function from libdep.so gets inlined all the way
into exe. This (unsurprisingly) means that the object file for exe references
symbols from libdep.so, which means that -ldep needs to be passed when linking
exe and it isn't. The fix is simply to pass it -- there is no harm in passing
it when it's not needed.

The thing is, it's not clear at all in the current code to see how the linker
can know that libdep2 is linked against libdep. It could look through the
DT_NEEDED entries in libdep2 and try to guess which are Go libraries, but it
feels better to be explicit. So this adds another SHT_NOTE section that lists
the shared libraries a shared library was linked against, and makes sure the
complete set of depended upon shared libraries is passed to the external
linker.

Change-Id: I79aa6f98b4db4721d657a7eb7b7f062269bf49e2
Reviewed-on: https://go-review.googlesource.com/10376
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2015-05-27 13:25:32 +00:00
Michael Hudson-Doyle
65518032b9 cmd/link/internal/ld: put abi hash into a note
This makes for a more stable API for tools (including cmd/link itself) to
extract the abi hash from a shared library and makes it possible at all for a
library that has had the local symbol table removed.

The existing note-writing code only supports writing notes into the very start
of the object file so they are easy to find in core dumps. This doesn't apply
to the "go" notes and means that all notes have to fit into a fixed size
budget. That's annoying now we have more notes (and the next CL will add
another one) so this does a little bit of work to make adding notes that do not
have to go at the start of the file easier and moves the writing of the package
list note over to that mechanism, which lets me revert a hack that increased
the size budget mentioned above for -buildmode=shared builds.

Change-Id: I6077a68d395c8a2bc43dec8506e73c71ef77d9b9
Reviewed-on: https://go-review.googlesource.com/10375
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2015-05-27 04:48:29 +00:00
Michael Hudson-Doyle
cf2736c4c5 cmd/link: replace interface{} fields with concrete types
The LSym.Section and Section.Elfsect fields were defined as interface{} but
always had the same concrete type (*Section and *ElfShdr respectively) so just
define them with that type. Reduces size of LSym from 328 to 320 bytes and
reduces best-of-10 maxresident size from 246028k to 238036k when linking
libstd.so.

Change-Id: Ie7112c53e4c2c7ce5fe233b81372aa5633f572e8
Reviewed-on: https://go-review.googlesource.com/10410
Reviewed-by: Minux Ma <minux@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2015-05-27 04:03:32 +00:00
Russ Cox
17eba6e6b7 cmd/compile, cmd/link: create from 5g, 5l, etc
Trivial merging of 5g, 6g, ... into go tool compile,
and similarlly 5l, 6l, ... into go tool link.
The files compile/main.go and link/main.go are new.
Everything else in those directories is a move followed by
change of imports and package name.

This CL breaks the build. Manual fixups are in the next CL.

See golang-dev thread titled "go tool compile, etc" for background.

Change-Id: Id35ff5a5859ad9037c61275d637b1bd51df6828b
Reviewed-on: https://go-review.googlesource.com/10287
Reviewed-by: Dave Cheney <dave@cheney.net>
Reviewed-by: Rob Pike <r@golang.org>
2015-05-21 17:31:51 +00:00
Renamed from src/cmd/internal/ld/elf.go (Browse further)