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Commit Graph

540 Commits

Author SHA1 Message Date
Elias Naur
3b68922575 misc/cgo/testcarchive: add missing header
write(2) is defined in unistd.h.

For the iOS builder.

Change-Id: I411ffe81988d8fbafffde89e4732a20af1a63325
Reviewed-on: https://go-review.googlesource.com/37962
Run-TryBot: Elias Naur <elias.naur@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
2017-03-09 16:42:46 +00:00
Bryan C. Mills
29edf0f9fe runtime: poll libc to deliver signals under TSAN
fixes #18717

Change-Id: I7244463d2e7489e0b0fe3b74c4b782e71210beb2
Reviewed-on: https://go-review.googlesource.com/35494
Run-TryBot: Bryan Mills <bcmills@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2017-03-08 18:58:30 +00:00
Ian Lance Taylor
e24228af25 runtime: enable/disable SIGPROF if needed when profiling
This ensures that SIGPROF is handled correctly when using
runtime/pprof in a c-archive or c-shared library.

Separate profiler handling into pre-process changes and per-thread
changes. Simplify the Windows code slightly accordingly.

Fixes #18220.

Change-Id: I5060f7084c91ef0bbe797848978bdc527c312777
Reviewed-on: https://go-review.googlesource.com/34018
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Austin Clements <austin@google.com>
Run-TryBot: Austin Clements <austin@google.com>
2017-02-09 18:53:34 +00:00
Elias Naur
78074f6850 runtime: handle SIGPIPE in c-archive and c-shared programs
Before this CL, Go programs in c-archive or c-shared buildmodes
would not handle SIGPIPE. That leads to surprising behaviour where
writes on a closed pipe or socket would raise SIGPIPE and terminate
the program. This CL changes the Go runtime to handle
SIGPIPE regardless of buildmode. In addition, SIGPIPE from non-Go
code is forwarded.

This is a refinement of CL 32796 that fixes the case where a non-default
handler for SIGPIPE is installed by the host C program.

Fixes #17393

Change-Id: Ia41186e52c1ac209d0a594bae9904166ae7df7de
Reviewed-on: https://go-review.googlesource.com/35960
Run-TryBot: Elias Naur <elias.naur@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2017-02-03 20:07:36 +00:00
Daniel Martí
329fff0db0 misc/cgo/testshared: remove unused flag.Parse()
TestMain doesn't make use of any flags.

Change-Id: I98ec582fb004045a5067618f605ccfeb1f9f4bbb
Reviewed-on: https://go-review.googlesource.com/33613
Reviewed-by: David Crawshaw <crawshaw@golang.org>
Run-TryBot: David Crawshaw <crawshaw@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2017-02-02 13:40:16 +00:00
David Crawshaw
b531eb3062 runtime: reorder modules so main.main comes first
Modules appear in the moduledata linked list in the order they are
loaded by the dynamic loader, with one exception: the
firstmoduledata itself the module that contains the runtime.
This is not always the first module (when using -buildmode=shared,
it is typically libstd.so, the second module).

The order matters for typelinksinit, so we swap the first module
with whatever module contains the main function.

Updates #18729

This fixes the test case extracted with -linkshared, and now

	go test -linkshared encoding/...

passes. However the original issue about a plugin failure is not
yet fixed.

Change-Id: I9f399ecc3518e22e6b0a350358e90b0baa44ac96
Reviewed-on: https://go-review.googlesource.com/35644
Run-TryBot: David Crawshaw <crawshaw@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Reviewed-by: Michael Hudson-Doyle <michael.hudson@canonical.com>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2017-01-25 22:33:57 +00:00
Ian Lance Taylor
1be957d703 misc/cgo/test: pass current environment to syscall.Exec
This is needed for typical tests with gccgo, as it passes the
LD_LIBRARY_PATH environment variable to the new program.

Change-Id: I9bf4b0dbdff63f5449c7fcb8124eaeab10ed7f34
Reviewed-on: https://go-review.googlesource.com/35481
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
2017-01-20 21:12:54 +00:00
Ian Lance Taylor
ec654e2251 misc/cgo/test: fix test when using GCC 7
With GCC 7 (not yet released), cgo fails with errors like

./sigaltstack.go:65:8: call of non-function C.restoreSignalStack

I do not know precisely why. Explicitly declaring that there are no
arguments to the static function is a simple fix for the debug info.

Change-Id: Id96e1cb1e55ee37a9f1f5ad243d7ee33e71584ac
Reviewed-on: https://go-review.googlesource.com/35480
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
2017-01-20 21:12:19 +00:00
Bryan C. Mills
ea7d9e6a52 runtime: check for nil g and m in msanread
fixes #18707.

Change-Id: Ibc4efef01197799f66d10bfead22faf8ac00473c
Reviewed-on: https://go-review.googlesource.com/35452
Run-TryBot: Bryan Mills <bcmills@google.com>
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2017-01-19 23:06:54 +00:00
Keith Randall
81a61a96c9 runtime: for plugins, don't add duplicate itabs
We already do this for shared libraries. Do it for plugins also.
Suggestions on how to test this would be welcome.

I'd like to get this in for 1.8.  It could lead to mysterious
hangs when using plugins.

Fixes #18676

Change-Id: I03209b096149090b9ba171c834c5e59087ed0f92
Reviewed-on: https://go-review.googlesource.com/35117
Reviewed-by: David Crawshaw <crawshaw@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Reviewed-by: Michael Hudson-Doyle <michael.hudson@canonical.com>
2017-01-17 22:37:19 +00:00
Keith Randall
4c4c5fc7a3 misc/cgo/testplugin: test that types and itabs are unique
Make sure that the same type and itab generated in two
different plugins are actually the same thing.

See also CL 35115

Change-Id: I0c1ecb039d7e2bf5a601d58dfa162a435ae4ef76
Reviewed-on: https://go-review.googlesource.com/35116
Run-TryBot: Keith Randall <khr@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: David Crawshaw <crawshaw@golang.org>
2017-01-13 17:31:33 +00:00
Keith Randall
08da8201ca misc/cgo/testshared: test that types and itabs are unique
Make sure that the same type and itab generated in two
different shared library are actually the same thing.

Change-Id: Ica45862d65ff8bc7ad04d59a41f57223f71224cd
Reviewed-on: https://go-review.googlesource.com/35115
Run-TryBot: Keith Randall <khr@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2017-01-12 00:20:55 +00:00
Ian Lance Taylor
d2512aff87 misc/cgo/test: limit issue18146 attempts based on RLIMIT_NPROC
Fixes #18381.

Change-Id: I0a476cd7f6182c8d4646628477c56c133d5671ee
Reviewed-on: https://go-review.googlesource.com/34667
Run-TryBot: Ian Lance Taylor <iant@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2016-12-21 22:50:41 +00:00
Ian Lance Taylor
860c9c0b8d misc/cgo/testcshared: wait up to 1 second in main2.c
Wait longer in case the system is heavily loaded.

Fixes #18324.

Change-Id: If9a6da1cf32d0321302d244ee24fb3f80e54489d
Reviewed-on: https://go-review.googlesource.com/34653
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
2016-12-20 05:06:55 +00:00
Michael Hudson-Doyle
1ec64e9b63 cmd/compile, runtime: a different approach to duplicate itabs
golang.org/issue/17594 was caused by additab being called more than once for
an itab. golang.org/cl/32131 fixed that by making the itabs local symbols,
but that in turn causes golang.org/issue/18252 because now there are now
multiple itab symbols in a process for a given (type,interface) pair and
different code paths can end up referring to different itabs which breaks
lots of reflection stuff. So this makes itabs global again and just takes
care to only call additab once for each itab.

Fixes #18252

Change-Id: I781a193e2f8dd80af145a3a971f6a25537f633ea
Reviewed-on: https://go-review.googlesource.com/34173
Run-TryBot: Michael Hudson-Doyle <michael.hudson@canonical.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: David Crawshaw <crawshaw@golang.org>
2016-12-19 01:31:59 +00:00
Ian Lance Taylor
115e9cac80 misc/cgo/testsanitizer: don't run msan tests if msan doesn't work
Confirm that a trivial executable can build and execute using
-fsanitize=memory.

Fixes #18335 (by skipping the tests when they don't work).

Change-Id: Icb7a276ba7b57ea3ce31be36f74352cc68dc89d5
Reviewed-on: https://go-review.googlesource.com/34505
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
2016-12-16 01:45:03 +00:00
Bryan C. Mills
29cb72154d runtime: preserve callee-saved C registers in sigtramp
This fixes Linux and the *BSD platforms on 386/amd64.

A few OS/arch combinations were already saving registers and/or doing
something that doesn't clearly resemble the SysV C ABI; those have
been left alone.

Fixes #18328.

Change-Id: I6398f6c71020de108fc8b26ca5946f0ba0258667
Reviewed-on: https://go-review.googlesource.com/34501
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2016-12-15 23:41:06 +00:00
Vladimir Stefanovic
92fb0a00c2 misc/cgo/test: add mipsx test case for #9400
Change-Id: I7d0bc5093943b0744d865e91517ff6292f3b2f89
Reviewed-on: https://go-review.googlesource.com/34510
Run-TryBot: Cherry Zhang <cherryyz@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
2016-12-15 17:05:29 +00:00
David Crawshaw
96414ca39f cmd/link: do not export plugin C symbols
Explicitly filter any C-only cgo functions out of pclntable,
which allows them to be duplicated with the host binary.

Updates #18190.

Change-Id: I50d8706777a6133b3e95f696bc0bc586b84faa9e
Reviewed-on: https://go-review.googlesource.com/34199
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2016-12-14 19:36:20 +00:00
Ian Lance Taylor
10f3b09027 cmd/cgo: don't strip qualifiers from C void* pointer
Now that we try to handle qualifiers correctly (as of CL 33325), don't
strip them from a void* pointer. Otherwise we break a case like "const
void**", as the "const" qualifier is dropped and the resulting
"void**" triggers a warning from the C compiler.

Fixes #18298.

Change-Id: If51df1889b0f6a907715298c152e6d4584747acb
Reviewed-on: https://go-review.googlesource.com/34370
Run-TryBot: Ian Lance Taylor <iant@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2016-12-14 00:59:38 +00:00
Vladimir Stefanovic
990cda59f8 misc/cgo/test: skip test18146 on mips{,64}
Change-Id: I724f4443fc10a6ee0d027a9533f07aba39455cfa
Reviewed-on: https://go-review.googlesource.com/34312
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2016-12-13 22:24:03 +00:00
Ian Lance Taylor
fded5dbb2f runtime: don't crash if signal delivered on g0 stack
Also, if we changed the gsignal stack to match the stack we are
executing on, restore it when returning from the signal handler, for
safety.

Fixes #18255.

Change-Id: Ic289b36e4e38a56f8a6d4b5d74f68121c242e81a
Reviewed-on: https://go-review.googlesource.com/34239
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Bryan Mills <bcmills@google.com>
Reviewed-by: David Crawshaw <crawshaw@golang.org>
2016-12-12 19:19:59 +00:00
David Crawshaw
ab5a2173f9 cmd/link: limit darwin dynlink symbol exports
The pclntable contains pointers to functions. If the function symbol
is exported in a plugin, and there is a matching symbol in the host
binary, then the pclntable of a plugin ends up pointing at the
function in the host module.

This doesn't work because the traceback code expects the pointer to
be in the same module space as the PC value.

So don't export functions that might overlap with the host binary.
This way the pointer stays in its module.

Updates #18190

Change-Id: Ifb77605b35fb0a1e7edeecfd22b1e335ed4bb392
Reviewed-on: https://go-review.googlesource.com/34196
Run-TryBot: David Crawshaw <crawshaw@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2016-12-10 17:03:45 +00:00
Michael Hudson-Doyle
67b2927990 cmd/link: do not mark go.plugin.tabs as reachable in non-plugins
Fixes #18250

Change-Id: I4f61591356ddb4a906c206ad8456d1839daf7b91
Reviewed-on: https://go-review.googlesource.com/34170
Run-TryBot: Michael Hudson-Doyle <michael.hudson@canonical.com>
Reviewed-by: David Crawshaw <crawshaw@golang.org>
2016-12-08 20:01:23 +00:00
Ian Lance Taylor
2641cffd41 misc/cgo/test: skip test18146 on Darwin
It is reported as failing for two people (issues #18202 and #18212).
The failure mode is that the system gets overloaded and other programs
fail to run.

Fixes #18202.

Change-Id: I1f1ca1f5d8eed6cc3a9dffac3289851e09fa662b
Reviewed-on: https://go-review.googlesource.com/34017
Run-TryBot: Ian Lance Taylor <iant@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
2016-12-07 05:02:32 +00:00
Ian Lance Taylor
6c9f600d49 misc/cgo/test: ignore "too many open files" in issue 18146 test
Seen on the OpenBSD/AMD64 builder:
https://build.golang.org/log/fa34df1bcd3af12d4fc0fb0e60e3c6197a2a6f75

Update #18146.

Change-Id: I2646621488be84d50f47c312baa0817c72e3c058
Reviewed-on: https://go-review.googlesource.com/33907
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
2016-12-06 02:44:58 +00:00
Ian Lance Taylor
80acfe950f runtime/cgo: retry pthread_create on EAGAIN for OpenBSD
For reasons that I do not know, OpenBSD does not call pthread_create
directly, but instead looks it up in libpthread.so. That means that we
can't use the code used on other systems to retry pthread_create on
EAGAIN, since that code simply calls pthread_create.

This patch copies that code to an OpenBSD-specific version.

Also, check for an EAGAIN failure in the test, as that seems to be the
underlying cause of the test failure on several systems including OpenBSD.

Fixes #18146.

Change-Id: I3bceaa1e03a7eaebc2da19c9cc146b25b59243ef
Reviewed-on: https://go-review.googlesource.com/33905
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
2016-12-05 21:15:05 +00:00
Ian Lance Taylor
a303f05f86 misc/cgo/test: skip Test18146 on DragonFly
Fails on builder for unknown reasons.

Fixes #18198.
Update #18146.

Change-Id: Iaa85826655eee57d86e0c73d06c930ef3f4647ec
Reviewed-on: https://go-review.googlesource.com/33906
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
2016-12-05 20:06:38 +00:00
Ian Lance Taylor
7cba779cea runtime/cgo: retry pthread_create on EAGAIN
Update #18146.

Change-Id: Ib447aabae9f203a8b61fb8c984b57d8e2bfe69c2
Reviewed-on: https://go-review.googlesource.com/33894
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
2016-12-05 18:46:18 +00:00
Elias Naur
0b2daa5650 Revert "runtime: handle SIGPIPE in c-archive and c-shared programs"
This reverts commit d24b57a6a1.

Reason for revert: Further complications arised (issue 18100). We'll try again in Go 1.9.

Change-Id: I5ca93d2643a4be877dd9c2d8df3359718440f02f
Reviewed-on: https://go-review.googlesource.com/33770
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Minux Ma <minux@golang.org>
Run-TryBot: Minux Ma <minux@golang.org>
2016-12-01 11:23:17 +00:00
Ian Lance Taylor
d4b704e110 cmd/cgo: fix cgo checking when fetching errno value
Fixes #18126.

Change-Id: I7ae090945ef203673b06eb94817cc5c894b5eadc
Reviewed-on: https://go-review.googlesource.com/33752
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
2016-12-01 02:13:50 +00:00
Austin Clements
f6bff1d587 runtime: fix undead arguments in cgocall
From the garbage collector's perspective, time can move backwards in
cgocall. However, in the midst of this time warp, the pointer
arguments to cgocall can go from dead back to live. If a stack growth
happens while they're dead and then a GC happens when they become live
again, GC can crash with a bad heap pointer.

Specifically, the sequence that leads to a panic is:

1. cgocall calls entersyscall, which saves the PC and SP of its call
site in cgocall. Call this PC/SP "X". At "X" both pointer arguments
are live.

2. cgocall calls asmcgocall. Call the PC/SP of this call "Y". At "Y"
neither pointer argument is live.

3. asmcgocall calls the C code, which eventually calls back into the
Go code.

4. cgocallbackg remembers the saved PC/SP "X" in some local variables,
calls exitsyscall, and then calls cgocallbackg1.

5. The Go code causes a stack growth. This stack unwind sees PC/SP "Y"
in the cgocall frame. Since the arguments are dead at "Y", they are
not adjusted.

6. The Go code returns to cgocallbackg1, which calls reentersyscall
with the recorded saved PC/SP "X", so "X" gets stashed back into
gp.syscallpc/sp.

7. GC scans the stack. It sees there's a saved syscall PC/SP, so it
starts the traceback at PC/SP "X". At "X" the arguments are considered
live, so it scans them, but since they weren't adjusted, the pointers
are bad, so it panics.

This issue started as of commit ca4089ad, when the compiler stopped
marking arguments as live for the whole function.

Since this is a variable liveness issue, fix it by adding KeepAlive
calls that keep the arguments live across this whole time warp.

The existing issue7978 test has all of the infrastructure for testing
this except that it's currently up to chance whether a stack growth
happens in the callback (it currently only happens on the
linux-amd64-noopt builder, for example). Update this test to force a
stack growth, which causes it to fail reliably without this fix.

Fixes #17785.

Change-Id: If706963819ee7814e6705693247bcb97a6f7adb8
Reviewed-on: https://go-review.googlesource.com/33710
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
2016-11-30 17:09:17 +00:00
Ian Lance Taylor
7dc97d9e32 misc/cgo/testcshared: add explicit ./ to shared library argument
Use an explicit ./ to make sure we link against the libgo.so we just
built, not some other libgo.so that the compiler or linker may decide to
seek out.

Fixes #17986.

Change-Id: Id23f6c95aa2b52f4f42c1b6dac45482c22b4290d
Reviewed-on: https://go-review.googlesource.com/33413
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
2016-11-19 04:31:36 +00:00
Elias Naur
d24b57a6a1 runtime: handle SIGPIPE in c-archive and c-shared programs
Before this CL, Go programs in c-archive or c-shared buildmodes
would not handle SIGPIPE. That leads to surprising behaviour where
writes on a closed pipe or socket would raise SIGPIPE and terminate
the program. This CL changes the Go runtime to handle
SIGPIPE regardless of buildmode. In addition, SIGPIPE from non-Go
code is forwarded.

Fixes #17393
Updates #16760

Change-Id: I155e82020a03a5cdc627a147c27da395662c3fe8
Reviewed-on: https://go-review.googlesource.com/32796
Run-TryBot: Elias Naur <elias.naur@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2016-11-18 01:19:11 +00:00
Ian Lance Taylor
7061dc3f6e cmd/cgo: ignore top-level qualifiers in function args/results
The top-level qualifiers are unimportant for our purposes. If a C
function is defined as `const int f(const int i)`, the `const`s are
meaningless to C, and we want to avoid using them in the struct we
create where the `const` has a completely different meaning.

This unwinds https://golang.org/cl/33097 with regard to top-level
qualifiers.

Change-Id: I3d66b0eb43b6d9a586d9cdedfae5a2306b46d96c
Reviewed-on: https://go-review.googlesource.com/33325
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Joe Tsai <thebrokentoaster@gmail.com>
2016-11-17 19:03:55 +00:00
Elias Naur
4ca3a8f7a8 misc/cgo: decrease test failure timeouts
CL 33239 changed the polling loops from using sched_yield to a sleep
for 1/1000 of a second. The loop counters were not updated, so failing
tests now take 100 seconds to complete. Lower the loop counts to 5
seconds instead.

Change-Id: I7c9a343dacc8188603ecf7e58bd00b535cfc87f5
Reviewed-on: https://go-review.googlesource.com/33280
Run-TryBot: Elias Naur <elias.naur@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2016-11-17 16:31:34 +00:00
David Crawshaw
7ee7936523 cmd/link: handle R_GOTPCREL separately on darwin
To generate the correct section offset the shared code path for
R_CALL, R_PCREL, and R_GOTPCREL on darwin when externally linking
walks up the symbol heirarchy adding the differences. This is fine,
except in the case where we are generating a GOT lookup, because
the topmost symbol is left in r.Xsym instead of the symbol we are
looking up. So all funcsym GOT lookups were looking up the outer
"go.func.*" symbol.

Fix this by separating out the R_GOTPCREL code path.

For #17828 (and may fix it).

Change-Id: I2c9f4d135e77c17270aa064d8c876dc6d485d659
Reviewed-on: https://go-review.googlesource.com/33211
Run-TryBot: David Crawshaw <crawshaw@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2016-11-16 18:37:03 +00:00
Bryan C. Mills
1f605175b0 runtime/cgo: use libc for sigaction syscalls when possible
This ensures that runtime's signal handlers pass through the TSAN and
MSAN libc interceptors and subsequent calls to the intercepted
sigaction function from C will correctly see them.

Fixes #17753.

Change-Id: I9798bb50291a4b8fa20caa39c02a4465ec40bb8d
Reviewed-on: https://go-review.googlesource.com/33142
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2016-11-16 05:38:38 +00:00
Ian Lance Taylor
27b68474ca cmd/cgo: run cgo pointer checks for pointer to union
If a C union type (or a C++ class type) can contain a pointer field,
then run the cgo checks on pointers to that type. This will test the
pointer as though it were an unsafe.Pointer, and will crash if it points
to Go memory that contains a pointer.

Fixes #15942.

Change-Id: Ic2d07ed9648d4b27078ae7683e26196bcbc59fc9
Reviewed-on: https://go-review.googlesource.com/33237
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
2016-11-15 17:10:52 +00:00
David Crawshaw
fab3fcaf75 cmd/go: use build ID as plugin symbol prefix
Updates #17821

Change-Id: Iebd2e88b2d4f3d757ffad72456f4bfc0607d8110
Reviewed-on: https://go-review.googlesource.com/33162
Run-TryBot: David Crawshaw <crawshaw@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2016-11-15 16:17:07 +00:00
David Crawshaw
03da2690c9 cmd/link, runtime, plugin: versioning
In plugins and every program that opens a plugin, include a hash of
every imported package.

There are two versions of each hash: one local and one exported.
As the program starts and plugins are loaded, the first exported
symbol for each package becomes the canonical version.

Any subsequent plugin's local package hash symbol has to match the
canonical version.

Fixes #17832

Change-Id: I4e62c8e1729d322e14b1673bada40fa7a74ea8bc
Reviewed-on: https://go-review.googlesource.com/33161
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2016-11-15 16:14:27 +00:00
Ian Lance Taylor
b687d6a788 misc/cgo/testcarchive, misc/cgo/testcshared: sleep instead of sched_yield
Apparently when GOMAXPROCS == 1 a simple sched_yield in a tight loop is
not necessarily sufficient to permit a signal handler to run. Instead,
sleep for 1/1000 of a second.

Fixes #16649.

Change-Id: I83910144228556e742b7a92a441732ef61aa49d9
Reviewed-on: https://go-review.googlesource.com/33239
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
2016-11-15 05:35:54 +00:00
Ian Lance Taylor
fb8c896aff cmd/cgo: don't ignore qualifiers, don't cast to void*
The cgo tool used to simply ignore C type qualifiers. To avoid problems
when a C function expected a qualifier that was not present, cgo emitted
a cast to void* around all pointer arguments. Unfortunately, that broke
code that contains both a function declaration and a macro, when the
macro required the argument to have the right type. To fix this problem,
don't ignore qualifiers. They are easy enough to handle for the limited
set of cases that matter for cgo, in which we don't care about array or
function types.

Fixes #17537.

Change-Id: Ie2988d21db6ee016a3e99b07f53cfb0f1243a020
Reviewed-on: https://go-review.googlesource.com/33097
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Russ Cox <rsc@golang.org>
2016-11-11 01:31:12 +00:00
Russ Cox
ced137fad4 misc/cgo/testsanitizers: skip tests when vm.overcommit_memory=2
Fixes #17689.

Change-Id: I45a14e6bf4b2647431105f3e0b63b7076b6655d2
Reviewed-on: https://go-review.googlesource.com/32635
Run-TryBot: Russ Cox <rsc@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2016-11-03 16:04:33 +00:00
David Crawshaw
8eb9fdaa01 cmd/compile: write type symbols referenced in ptabs
The exported symbol for a plugin can be the only reference to a
type in a program. In particular, "var F func()" will have
the type *func(), which is uncommon.

Fixes #17140

Change-Id: Ide2104edbf087565f5377374057ae54e0c00c57e
Reviewed-on: https://go-review.googlesource.com/29692
Run-TryBot: David Crawshaw <crawshaw@golang.org>
Reviewed-by: Russ Cox <rsc@golang.org>
2016-11-03 14:07:34 +00:00
Ian Lance Taylor
689947d565 cmd/cgo: only record typedef name for pointer to struct
In a function argument, we handle a typedef for a pointer specially,
using the pointer type rather than the typedef, to permit the Go calls
to match the laxer type conversions permitted in C. We record the
typedef so that we use that type in the C code, in case it has a special
attribute. However, using the typedef is wrong when using a pointer to a
basic type, because the C code may sometimes use the typedef and
sometimes not, and using the typedef in all cases will cause incorrect
type errors on the Go side. Fortunately we only really need to use the
typedef when pointing to a struct/union/class, and in such a case
confusion is unlikely.

Fixes #17723.

Change-Id: Id2eaeb156faeaf2e8eb9cf0b8f95b44caf8cfbd2
Reviewed-on: https://go-review.googlesource.com/32536
Run-TryBot: Ian Lance Taylor <iant@golang.org>
Reviewed-by: David Crawshaw <crawshaw@golang.org>
2016-11-01 23:06:24 +00:00
David Crawshaw
d0e408334b cmd/link: support plugins with no exported symbols
A plugin with no exported symbols is still potentially very useful.
Its init functions are called on load, and it so it can have visible
side effects.

Fixes #17681

Change-Id: Icdca31f48e5ab13c99020a2ef724f3de47dcd74b
Reviewed-on: https://go-review.googlesource.com/32437
Run-TryBot: David Crawshaw <crawshaw@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2016-11-01 20:56:30 +00:00
Bryan C. Mills
8380de416b runtime: align stack pointer in sigfwd
sigfwd calls an arbitrary C signal handler function.  The System V ABI
for x86_64 (and the most recent revision of the ABI for i386) requires
the stack to be 16-byte aligned.

Fixes: #17641

Change-Id: I77f53d4a8c29c1b0fe8cfbcc8d5381c4e6f75a6b
Reviewed-on: https://go-review.googlesource.com/32107
Run-TryBot: Bryan Mills <bcmills@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2016-11-01 17:37:43 +00:00
David Crawshaw
9da7058466 cmd/link, plugin: use full plugin path for symbols
Plumb the import path of a plugin package through to the linker, and
use it as the prefix on the exported symbol names.

Before this we used the basename of the plugin file as the prefix,
which could conflict and result in multiple loaded plugins sharing
symbols that are distinct.

Fixes #17155
Fixes #17579

Change-Id: I7ce966ca82d04e8507c0bcb8ea4ad946809b1ef5
Reviewed-on: https://go-review.googlesource.com/32355
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2016-10-31 04:48:42 +00:00
Ian Lance Taylor
f135106ec7 cmd/cgo: add -srcdir option
This is convenient for direct use of `go tool cgo`. We can also use it
from the go tool to reduce the length of the file names that cgo
generates.

Update #17070.

Change-Id: I8466a0a2cc68a732d17d07319e303497715bac8c
Reviewed-on: https://go-review.googlesource.com/32354
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Russ Cox <rsc@golang.org>
2016-10-30 19:14:08 +00:00
Michael Hudson-Doyle
8b07ec20f7 cmd/compile, runtime: make the go.itab.* symbols module-local
Otherwise, the way the ELF dynamic linker works means that you can end up with
the same itab being passed to additab twice, leading to the itab linked list
having a cycle in it. Add a test to additab in runtime to catch this when it
happens, not some arbitrary and surprsing time later.

Fixes #17594

Change-Id: I6c82edcc9ac88ac188d1185370242dc92f46b1ad
Reviewed-on: https://go-review.googlesource.com/32131
Run-TryBot: Michael Hudson-Doyle <michael.hudson@canonical.com>
Reviewed-by: David Crawshaw <crawshaw@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2016-10-27 19:13:35 +00:00
Ian Lance Taylor
e24ccfc6fc misc/cgo/errors: fix malloc test for dragonfly
The Dragonfly libc returns a non-zero value for malloc(-1).

Fixes #17585.

Change-Id: Icfe68011ccbc75c676273ee3c3efdf24a520a004
Reviewed-on: https://go-review.googlesource.com/32050
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
2016-10-25 20:11:50 +00:00
Ian Lance Taylor
b4ce38ec57 cmd/cgo: throw if C.malloc returns nil
Change-Id: If7740ac7b6c4190db5a1ab4100d12cf16dc79c84
Reviewed-on: https://go-review.googlesource.com/31768
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Russ Cox <rsc@golang.org>
2016-10-25 02:38:49 +00:00
Ian Lance Taylor
b7c7949817 cmd/cgo: preserve original call arguments when pointer checking
With the old code rewriting refs would rewrite the inner arguments
rather than the outer ones, leaving a reference to C.val in the outer
arguments.

Change-Id: I9b91cb4179eccd08500d14c6591bb15acf8673eb
Reviewed-on: https://go-review.googlesource.com/31672
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
2016-10-21 20:46:20 +00:00
Ian Lance Taylor
a16954b8a7 cmd/cgo: always use a function literal for pointer checking
The pointer checking code needs to know the exact type of the parameter
expected by the C function, so that it can use a type assertion to
convert the empty interface returned by cgoCheckPointer to the correct
type. Previously this was done by using a type conversion, but that
meant that the code accepted arguments that were convertible to the
parameter type, rather than arguments that were assignable as in a
normal function call. In other words, some code that should not have
passed type checking was accepted.

This CL changes cgo to always use a function literal for pointer
checking. Now the argument is passed to the function literal, which has
the correct argument type, so type checking is performed just as for a
function call as it should be.

Since we now always use a function literal, simplify the checking code
to run as a statement by itself. It now no longer needs to return a
value, and we no longer need a type assertion.

This does have the cost of introducing another function call into any
call to a C function that requires pointer checking, but the cost of the
additional call should be minimal compared to the cost of pointer
checking.

Fixes #16591.

Change-Id: I220165564cf69db9fd5f746532d7f977a5b2c989
Reviewed-on: https://go-review.googlesource.com/31233
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
2016-10-19 21:20:50 +00:00
Alex Brainman
d8cbc2c918 misc/cgo/testcarchive: do not use same executable name in TestInstall
Fixes #17439

Change-Id: I7caa28519f38692f9ca306f0789cbb975fa1d7c4
Reviewed-on: https://go-review.googlesource.com/31112
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Run-TryBot: Ian Lance Taylor <iant@golang.org>
Run-TryBot: Alex Brainman <alex.brainman@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2016-10-17 00:34:12 +00:00
Xia Bin
347259cbae misc/cgo/test: add test that gccgo fails
Gccgo isn't locking the OS thread properly during calls.

Change-Id: Idb2475291405e390cbb83abb27a402fd0381d0c4
Reviewed-on: https://go-review.googlesource.com/18882
Run-TryBot: Russ Cox <rsc@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Russ Cox <rsc@golang.org>
2016-10-13 00:03:57 +00:00
Matthew Dempsky
f54c0db859 cmd/compile, cmd/cgo: align complex{64,128} like GCC
complex64 and complex128 are treated like [2]float32 and [2]float64,
so it makes sense to align them the same way.

Change-Id: Ic614bcdcc91b080aeb1ad1fed6fc15ba5a2971f8
Reviewed-on: https://go-review.googlesource.com/19800
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Russ Cox <rsc@golang.org>
2016-10-05 17:44:27 +00:00
David Crawshaw
1df438f79c misc/cgo/testplugin: add test of -buildmode=plugin
Change-Id: Ie9fea9814c850b084562ab2349b54d9ad9fa1f4a
Reviewed-on: https://go-review.googlesource.com/27825
Run-TryBot: David Crawshaw <crawshaw@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2016-09-16 17:55:24 +00:00
Michael Hudson-Doyle
8f9671d11a cmd/link: fix -buildmode=pie / -linkshared combination
main.main and main.init were not being marked as reachable.

Fixes #17076

Change-Id: Ib3e29bd35ba6252962e6ba89173ca321ed6849b9
Reviewed-on: https://go-review.googlesource.com/28996
Reviewed-by: David Crawshaw <crawshaw@golang.org>
Run-TryBot: David Crawshaw <crawshaw@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2016-09-13 02:40:30 +00:00
Josh Bleecher Snyder
aada57f39b misc/cgo/test: add skipped test for issue 17065
Updates #17065

Change-Id: I113caced6de666a9b032ab2684ece79482aa7357
Reviewed-on: https://go-review.googlesource.com/28964
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2016-09-11 20:43:11 +00:00
Alex Brainman
dfbbe06a20 cmd/link, cmd/go: delay linking of mingwex and mingw32 until very end
cmd/go links mingwex and mingw32 libraries to every package it builds.
This breaks when 2 different packages call same gcc standard library
function pow. gcc linker appends pow implementation to the compiled
package, and names that function "pow". But when these 2 compiled
packages are linked together into the final executable, linker
complains, because it finds two "pow" functions with the same name.

This CL stops linking of mingwex and mingw32 during package build -
that leaves pow function reference unresolved. pow reference gets
resolved as final executable is built, by having both internal and
external linker use mingwex and mingw32 libraries.

Fixes #8756

Change-Id: I50ddc79529ea5463c67118d668488345ecf069bc
Reviewed-on: https://go-review.googlesource.com/26670
Run-TryBot: Alex Brainman <alex.brainman@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2016-08-31 06:30:26 +00:00
Josh Bleecher Snyder
d1383b5b8f misc/cgo/testsigfwd: add missing return statement
Fixes C compiler warning:

./main.go:54:1: warning: control reaches end of non-void function [-Wreturn-type]

Should help fix the linux builders
that broke due to CL 23005.

Change-Id: Ib0630798125e35a12f99d666b7ffe7b3196f0ecc
Reviewed-on: https://go-review.googlesource.com/28176
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
2016-08-30 21:44:14 +00:00
Josh Bleecher Snyder
a46ea90705 go/build: don't alter InstallSuffix for default compile options
Fixes #16378.

Change-Id: I99a064f1afec78fb63cb3719061d20be0f21d45d
Reviewed-on: https://go-review.googlesource.com/24930
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2016-08-26 23:01:37 +00:00
Ian Lance Taylor
2d85e87f08 runtime/cgo: add tsan acquire/release around setenv/unsetenv
Change-Id: Iabb25e97714d070c31c657559a97a3bfc979da18
Reviewed-on: https://go-review.googlesource.com/25403
Reviewed-by: Dmitry Vyukov <dvyukov@google.com>
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2016-08-23 14:07:58 +00:00
Ian Lance Taylor
d92a3606f5 cmd/go, cmd/link: build c-archive as position independent on ELF
This permits people to use -buildmode=c-archive to produce an archive
file that can be included in a PIE or shared library.

Change-Id: Ie340ee2f08bcff4f6fd1415f7d96d51ee3a7c9a1
Reviewed-on: https://go-review.googlesource.com/24180
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: David Crawshaw <crawshaw@golang.org>
2016-08-23 13:12:56 +00:00
Ian Lance Taylor
dc9755c2a2 runtime: add missing race and msan checks to reflect functions
Add missing race and msan checks to reflect.typedmmemove and
reflect.typedslicecopy. Missing these checks caused the race detector
to miss races and caused msan to issue false positive errors.

Fixes #16281.

Change-Id: I500b5f92bd68dc99dd5d6f297827fd5d2609e88b
Reviewed-on: https://go-review.googlesource.com/24760
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Dmitry Vyukov <dvyukov@google.com>
2016-08-23 13:12:15 +00:00
David Chase
5b9ff11c3d cmd/compile: ppc64le working, not optimized enough
This time with the cherry-pick from the proper patch of
the old CL.

Stack size increased.
Corrected NaN-comparison glitches.
Marked g register as clobbered by calls.
Fixed shared libraries.

live_ssa.go still disabled because of differences.
Presumably turning on more optimization will fix
both the stack size and the live_ssa.go glitches.

Enhanced debugging output for shared libs test.

Rebased onto master.

Updates #16010.

Change-Id: I40864faf1ef32c118fb141b7ef8e854498e6b2c4
Reviewed-on: https://go-review.googlesource.com/27159
Run-TryBot: David Chase <drchase@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
2016-08-18 16:34:47 +00:00
qeed
d282427248 cmd/cgo: error, not panic, if not enough arguments to function
Fixes #16116.

Change-Id: Ic3cb0b95382bb683368743bda49b4eb5fdcc35c0
Reviewed-on: https://go-review.googlesource.com/24286
Reviewed-by: Emmanuel Odeke <emm.odeke@gmail.com>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2016-06-21 04:32:04 +00:00
Ian Lance Taylor
837984f372 cmd/cgo: use function arg type for _cgoCheckPointerN function
When cgo writes a _cgoCheckPointerN function to handle unsafe.Pointer,
use the function's argument type rather than interface{}. This permits
type errors to be detected at build time rather than run time.

Fixes #13830.

Change-Id: Ic7090905e16b977e2379670e0f83640dc192b565
Reviewed-on: https://go-review.googlesource.com/23675
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Austin Clements <austin@google.com>
2016-06-09 16:02:03 +00:00
Ian Lance Taylor
d1b5d08f34 misc/cgo/testsanitizers: don't run some TSAN tests on GCC < 7
Before GCC 7 defined __SANITIZE_THREAD__ when using TSAN,
runtime/cgo/libcgo.h could not determine reliably whether TSAN was in
use when using GCC.

Fixes #15983.

Change-Id: I5581c9f88e1cde1974c280008b2230fe5e971f44
Reviewed-on: https://go-review.googlesource.com/23833
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Michael Hudson-Doyle <michael.hudson@canonical.com>
2016-06-08 05:08:11 +00:00
Ian Lance Taylor
7b48020cfe cmd/cgo: check pointers for deferred C calls at the right time
We used to check time at the point of the defer statement. This change
fixes cgo to check them when the deferred function is executed.

Fixes #15921.

Change-Id: I72a10e26373cad6ad092773e9ebec4add29b9561
Reviewed-on: https://go-review.googlesource.com/23650
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Austin Clements <austin@google.com>
2016-06-03 20:51:39 +00:00
Ian Lance Taylor
cf862478c8 runtime/cgo: add TSAN locks around mmap call
Change-Id: I806cc5523b7b5e3278d01074bc89900d78700e0c
Reviewed-on: https://go-review.googlesource.com/23736
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Dmitry Vyukov <dvyukov@google.com>
2016-06-03 18:26:01 +00:00
Michael Hudson-Doyle
26849746c9 cmd/internal/obj, runtime: fixes for defer in 386 shared libraries
Any defer in a shared object crashed when GOARCH=386. This turns out to be two
bugs:

 1) Calls to morestack were not processed to be PIC safe (must have been
    possible to trigger this another way too)
 2) jmpdefer needs to rewind the return address of the deferred function past
    the instructions that load the GOT pointer into BX, not just past the call

Bug 2) requires re-introducing the a way for .s files to know when they are
being compiled for dynamic linking but I've tried to do that in as minimal
a way as possible.

Fixes #15916

Change-Id: Ia0d09b69ec272a176934176b8eaef5f3bfcacf04
Reviewed-on: https://go-review.googlesource.com/23623
Run-TryBot: Michael Hudson-Doyle <michael.hudson@canonical.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2016-06-03 02:50:27 +00:00
Elias Naur
6c4f8cd0d1 misc/cgo/test: fix issue9400 test on android/386
The test for #9400 relies on an assembler function that manipulates
the stack pointer. Meanwile, it uses a global variable for
synchronization. However, position independent code on 386 use a
function call to fetch the base address for global variables.
That function call in turn overwrites the Go stack.

Fix that by fetching the global variable address once before the
stack register manipulation.

Fixes the android/386 builder.

Change-Id: Ib77bd80affaa12f09d582d09d8b84a73bd021b60
Reviewed-on: https://go-review.googlesource.com/23683
Run-TryBot: Elias Naur <elias.naur@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: David Crawshaw <crawshaw@golang.org>
2016-06-02 14:01:47 +00:00
Elias Naur
42c51debe8 misc/cgo/test,cmd/dist: enable (more) Cgo tests on iOS
For #15919

Change-Id: I9fc38d9c8a9cc9406b551315e1599750fe212d0d
Reviewed-on: https://go-review.googlesource.com/23635
Reviewed-by: David Crawshaw <crawshaw@golang.org>
Run-TryBot: Elias Naur <elias.naur@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2016-06-02 10:09:12 +00:00
Michael Hudson-Doyle
d25c3eadea cmd/compile: do not generate tail calls when dynamic linking on ppc64le
When a wrapper method calls the real implementation, it's not possible to use a
tail call when dynamic linking on ppc64le. The bad scenario is when a local
call is made to the wrapper: the wrapper will call the implementation, which
might be in a different module and so set the TOC to the appropriate value for
that module. But if it returns directly to the wrapper's caller, nothing will
reset it to the correct value for that function.

Change-Id: Icebf24c9a2a0a9a7c2bce6bd6f1358657284fb10
Reviewed-on: https://go-review.googlesource.com/23468
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Run-TryBot: Michael Hudson-Doyle <michael.hudson@canonical.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2016-06-02 02:34:01 +00:00
Elias Naur
6de014b9e2 misc/cgo/test,cmd/dist: enable (most) Cgo tests on Android
Some tests cannot build for Android; use build tags and stubs to
skip them.

For #15919

Change-Id: Ieedcb73d4cabe23c3775cfb1d44c1276982dccd9
Reviewed-on: https://go-review.googlesource.com/23634
Run-TryBot: Elias Naur <elias.naur@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: David Crawshaw <crawshaw@golang.org>
2016-06-01 22:06:51 +00:00
Ian Lance Taylor
66736880ca runtime/cgo: add TSAN acquire/release calls
Add TSAN acquire/release calls to runtime/cgo to match the ones
generated by cgo.  This avoids a false positive race around the malloc
memory used in runtime/cgo when other goroutines are simultaneously
calling malloc and free from cgo.

These new calls will only be used when building with CGO_CFLAGS and
CGO_LDFLAGS set to -fsanitize=thread, which becomes a requirement to
avoid all false positives when using TSAN.  These are needed not just
for runtime/cgo, but also for any runtime package that uses cgo (such as
net and os/user).

Add an unused attribute to the _cgo_tsan_acquire and _cgo_tsan_release
functions, in case there are no actual cgo function calls.

Add a test that checks that setting CGO_CFLAGS/CGO_LDFLAGS avoids a
false positive report when using os/user.

Change-Id: I0905c644ff7f003b6718aac782393fa219514c48
Reviewed-on: https://go-review.googlesource.com/23492
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Dmitry Vyukov <dvyukov@google.com>
2016-05-31 20:53:16 +00:00
Ian Lance Taylor
b5d18b50ac cmd/cgo: remove -O options when generating compiler errors
The cgo tool generates compiler errors to find out what kind of name it
is using.  Turning on optimization can confuse that process by producing
new unexpected messages.

Fixes #14669.

Change-Id: Idc8e35fd259711ecc9638566b691c11d17140325
Reviewed-on: https://go-review.googlesource.com/23231
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Russ Cox <rsc@golang.org>
2016-05-27 01:40:30 +00:00
Ian Lance Taylor
a5d1a72a40 cmd/cgo, runtime, runtime/cgo: TSAN support for malloc
Acquire and release the TSAN synchronization point when calling malloc,
just as we do when calling any other C function. If we don't do this,
TSAN will report false positive errors about races calling malloc and
free.

We used to have a special code path for malloc and free, going through
the runtime functions cmalloc and cfree. The special code path for cfree
was no longer used even before this CL. This CL stops using the special
code path for malloc, because there is no place along that path where we
could conditionally insert the TSAN synchronization. This CL removes
the support for the special code path for both functions.

Instead, cgo now automatically generates the malloc function as though
it were referenced as C.malloc.  We need to automatically generate it
even if C.malloc is not called, even if malloc and size_t are not
declared, to support cgo-provided functions like C.CString.

Change-Id: I829854ec0787a80f33fa0a8a0dc2ee1d617830e2
Reviewed-on: https://go-review.googlesource.com/23260
Reviewed-by: Dmitry Vyukov <dvyukov@google.com>
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Austin Clements <austin@google.com>
2016-05-25 23:22:24 +00:00
Ian Lance Taylor
79ba1e44c7 cmd/cgo: mark stub functions as no_sanitize_thread
When the generated stub functions write back the results to the stack,
they can in some cases be writing to the same memory on the g0 stack.
There is no race here (assuming there is no race in the Go code), but
the thread sanitizer does not know that.  Turn off the thread sanitizer
for the stub functions to prevent false positive warnings.

Current clang suggests the no_sanitize("thread") attribute, but that
does not work with clang 3.6 or GCC.  clang 3.6, GCC, and current clang
all support the no_sanitize_thread attribute, so use that
unconditionally.

The test case and first version of the patch are from Dmitriy Vyukov.

Change-Id: I80ce92824c6c8cf88ea0fe44f21cf50cf62474c9
Reviewed-on: https://go-review.googlesource.com/23252
Run-TryBot: Ian Lance Taylor <iant@golang.org>
Reviewed-by: Dmitry Vyukov <dvyukov@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2016-05-19 17:29:13 +00:00
Ian Lance Taylor
538537a28d runtime: check only up to ptrdata bytes for pointers
Fixes #14508.

Change-Id: I237d0c5a79a73e6c97bdb2077d8ede613128b978
Reviewed-on: https://go-review.googlesource.com/23224
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Austin Clements <austin@google.com>
2016-05-18 23:39:06 +00:00
Elias Naur
fa270ad98e cmd/go: add -shared to darwin/arm{,64} default build mode
Buildmode c-archive now supports position independent code for
darwin/arm (in addition to darwin/arm64). Make PIC (-shared) the
default for both platforms in the default buildmode.

Without this change, gomobile will go install the standard library
into its separate package directory without PIC support.

Also add -shared to darwin/arm64 in buildmode c-archive, for
symmetry (darwin/arm64 always generates position independent code).

Fixes #15519

Change-Id: If27d2cbea8f40982e14df25da2703cbba572b5c6
Reviewed-on: https://go-review.googlesource.com/22920
Reviewed-by: David Crawshaw <crawshaw@golang.org>
Run-TryBot: David Crawshaw <crawshaw@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2016-05-07 18:58:39 +00:00
Ian Lance Taylor
a1813ae0a0 misc/cgo/testcarchive: avoid possible pthread_create race
The old code assumed that the thread ID set by pthread_create would be
available in the newly created thread.  While that is clearly true
eventually, it is not necessarily true immediately.  Rather than try to
pass down the thread ID, just call pthread_self in the created thread.

Fixes #15576 (I hope).

Change-Id: Ic07086b00e4fd5676c04719a299c583320da64a1
Reviewed-on: https://go-review.googlesource.com/22880
Run-TryBot: Ian Lance Taylor <iant@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
2016-05-06 19:15:52 +00:00
Elias Naur
e558fdbd9a misc/cgo/testcarchive: don't force -no_pie on Darwin
Now that darwin/arm supports position independent code, allow the
binaries generated by the c-archive tests be position independent
(PIE) as well.

Change-Id: If0517f06e92349ada29a4e3e0a951f08b0fcc710
Reviewed-on: https://go-review.googlesource.com/22841
Reviewed-by: David Crawshaw <crawshaw@golang.org>
Run-TryBot: Elias Naur <elias.naur@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2016-05-06 15:19:55 +00:00
Cherry Zhang
094e5a9288 misc/cgo/test: add mips64x test case for issue9400
Change-Id: If2b4abb6ff322c20e35de025298c8e5ab53edd42
Reviewed-on: https://go-review.googlesource.com/19808
Reviewed-by: Minux Ma <minux@golang.org>
2016-05-04 16:41:36 +00:00
Martin Möhrmann
082881daf8 misc/cgo/fortran: fix gfortran compile test
Fixes #14544

Change-Id: I58b0b164ebbfeafe4ab32039a063df53e3018a6d
Reviewed-on: https://go-review.googlesource.com/22730
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Reviewed-by: Sean Lake <odysseus9672@gmail.com>
2016-05-04 15:08:16 +00:00
Michael Hudson-Doyle
2f41edf120 cmd/link: always read type data for dynimport symbols
Consider three shared libraries:

 libBase.so -- defines a type T
 lib2.so    -- references type T
 lib3.so    -- also references type T, and something from lib2

lib2.so will contain a type symbol for T in its symbol table, but no
definition. If, when linking lib3.so the linker reads the symbols from lib2.so
before libBase.so, the linker didn't read the type data and later crashed.

The fix is trivial but the test change is a bit messy because the order the
linker reads the shared libraries in ends up depending on the order of the
import statements in the file so I had to rename one of the test packages so
that gofmt doesn't fix the test by accident...

Fixes #15516

Change-Id: I124b058f782c900a3a54c15ed66a0d91d0cde5ce
Reviewed-on: https://go-review.googlesource.com/22744
Run-TryBot: Michael Hudson-Doyle <michael.hudson@canonical.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2016-05-04 07:13:01 +00:00
Emmanuel Odeke
53fd522c0d all: make copyright headers consistent with one space after period
Follows suit with https://go-review.googlesource.com/#/c/20111.

Generated by running
$ grep -R 'Go Authors.  All' * | cut -d":" -f1 | while read F;do perl -pi -e 's/Go
Authors.  All/Go Authors. All/g' $F;done

The code in cmd/internal/unvendor wasn't changed.

Fixes #15213

Change-Id: I4f235cee0a62ec435f9e8540a1ec08ae03b1a75f
Reviewed-on: https://go-review.googlesource.com/21819
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2016-05-02 13:43:18 +00:00
Ian Lance Taylor
e50346d26a cmd/cgo, misc/cgo/test: make -Wdeclaration-after-statement clean
I got a complaint that cgo output triggers warnings with
-Wdeclaration-after-statement.  I don't think it's worth testing for
this--C has permitted declarations after statements since C99--but it is
easy enough to fix.  It may break again; so it goes.

This CL also fixes errno handling to avoid getting confused if the tsan
functions happen to change the global errno variable.

Change-Id: I0ec7c63a6be5653ef44799d134c8d27cb5efa441
Reviewed-on: https://go-review.googlesource.com/22686
Run-TryBot: Ian Lance Taylor <iant@golang.org>
Reviewed-by: Minux Ma <minux@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2016-05-02 04:42:12 +00:00
Cherry Zhang
94e523cb52 misc/cgo/testcarchive: fix C include path for darwin/arm
After CL 22461, c-archive build on darwin/arm is by default compiled
with -shared and installed in pkg/darwin_arm_shared.

Fix build (2nd time...)

Change-Id: Ia2bb09bb6e1ebc9bc74f7570dd80c81d05eaf744
Reviewed-on: https://go-review.googlesource.com/22534
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>
2016-04-29 12:21:27 +00:00
Cherry Zhang
78bcdeb6a3 misc/cgo/testcarchive: fix path of libgo.a for darwin/arm
After CL 22461, c-archive build on darwin/arm is by default compiled
with -shared, so update the install path.

Fix build.

Change-Id: Ie93dbd226ed416b834da0234210f4b98bc0e3606
Reviewed-on: https://go-review.googlesource.com/22507
Reviewed-by: David Crawshaw <crawshaw@golang.org>
Run-TryBot: David Crawshaw <crawshaw@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2016-04-27 20:07:12 +00:00
David Crawshaw
a3c92c9db1 cmd/link: use gold when dynamic linking on arm64
The GNU linker follows the letter of -znocopyreloc by refusing to
generate COPY relocations on arm64. Unfortunately it generates an
error instead of finding another way. The gold linker works, so
switch to it.

Fixes linux/arm64 build.

Change-Id: I1f7119d999c8f9f1f2d0c1e06b6462cea9c02a71
Reviewed-on: https://go-review.googlesource.com/22185
Run-TryBot: David Crawshaw <crawshaw@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
2016-04-18 16:14:44 +00:00
Mikio Hara
6f59ccb052 runtime: don't always unblock all signals on dragonfly, freebsd and openbsd
https://golang.org/cl/10173 intrduced msigsave, ensureSigM and
_SigUnblock but didn't enable the new signal save/restore mechanism for
SIG{HUP,INT,QUIT,ABRT,TERM} on DragonFly BSD, FreeBSD and OpenBSD.

At present, it looks like they have the implementation. This change
enables the new mechanism on DragonFly BSD, FreeBSD and OpenBSD the same
as Darwin, NetBSD.

Change-Id: Ifb4b4743b3b4f50bfcdc7cf1fe1b59c377fa2a41
Reviewed-on: https://go-review.googlesource.com/18657
Run-TryBot: Mikio Hara <mikioh.mikioh@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2016-04-15 21:20:45 +00:00
Dmitry Vyukov
0435e88a11 runtime: revert "do not call timeBeginPeriod on windows"
This reverts commit ab4c9298b8.

Sysmon critically depends on system timer resolution for retaking
of Ps blocked in system calls. See #14790 for an example
of a program where execution time goes from 2ms to 30ms if
timeBeginPeriod(1) is not used.

We can remove timeBeginPeriod(1) when we support UMS (#7876).

Update #14790

Change-Id: I362b56154359b2c52d47f9f2468fe012b481cf6d
Reviewed-on: https://go-review.googlesource.com/20834
Reviewed-by: Austin Clements <austin@google.com>
Run-TryBot: Dmitry Vyukov <dvyukov@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Alex Brainman <alex.brainman@gmail.com>
2016-04-09 16:11:41 +00:00
Christopher Nelson
ed8f0e5c33 cmd/go: fix -buildmode=c-archive should work on windows
Add supporting code for runtime initialization, including both
32- and 64-bit x86 architectures.

Add .ctors section on Windows to PE .o files, and INITENTRY to .ctors
section to plug in to the GCC C/C++ startup initialization mechanism.
This allows the Go runtime to initialize itself. Add .text section
symbol for .ctor relocations. Note: This is unlikely to be useful for
MSVC-based toolchains.

Fixes #13494

Change-Id: I4286a96f70e5f5228acae88eef46e2bed95813f3
Reviewed-on: https://go-review.googlesource.com/18057
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Run-TryBot: Ian Lance Taylor <iant@golang.org>
2016-04-04 03:38:25 +00:00
Eric Engestrom
7a8caf7d43 all: fix spelling mistakes
Signed-off-by: Eric Engestrom <eric@engestrom.ch>

Change-Id: I91873aaebf79bdf1c00d38aacc1a1fb8d79656a7
Reviewed-on: https://go-review.googlesource.com/21433
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2016-04-03 17:03:15 +00:00
Ian Lance Taylor
c61a55d831 misc/cgo/testcarchive: more robust TestSignalForwardingExternal
Try to avoid a race condition in the test.  Passed 500 times on my
laptop.

Fixes #14956.

Change-Id: I5de2e1e3623832f0ab4f180149f7c57ce7cd23c0
Reviewed-on: https://go-review.googlesource.com/21171
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
2016-03-26 02:40:12 +00:00
Christopher Nelson
93c5fbf390 misc/cgo/testcarchive: split main.c into unix and non-unix
This is in support of https://golang.org/cl/18057 which adds
support for c-archive to the Windows platform.

The signal handling tests do not compile on Windows. This splits
them out into a separate main_unix.c file, and conditionally
includes them for non-Windows platforms.

Change-Id: Ic79ce83da7656d6703505e514554748a482b81a1
Reviewed-on: https://go-review.googlesource.com/21086
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2016-03-26 00:57:23 +00:00
Elias Naur
95add73abf misc/cgo/testcarchive: fix build
I failed to rebase (and re-test) CL 21102 before submit, which meant
that two extra tests sneaked into testcarchive that still referenced
runtime.GOOS and runtime.GOARCH.

Convert the new tests.

While we're here, make sure pending tasks are flushed before running
the host tests. If not, the "##### misc/cgo/testcarchive" banner
and "PASS" won't show up in the all.bash output.

Change-Id: I41fc4ec9515f9a193fa052f7c31fac452153c897
Reviewed-on: https://go-review.googlesource.com/21106
Run-TryBot: Elias Naur <elias.naur@gmail.com>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2016-03-25 00:55:07 +00:00
Elias Naur
0a82ed5d7c misc/cgo/testcarchive: re-enable c-archive test on iOS and Android
The c-archive test were recently converted from shell script to Go.
Unfortunately, it also lost the ability to target iOS and Android
that lack C compilers and require exec wrappers.

Compile the c-archive test for the host and run it with the target
GOOS/GOARCH environment. Change the test to rely on go env GOOS
and go env GOARCH instead of runtime.GOOS and runtime.GOARCH.

Fixes #8345

Change-Id: I290ace2f7e96b87c55d99492feb7d660140dcb32
Reviewed-on: https://go-review.googlesource.com/21102
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2016-03-24 23:43:27 +00:00
Joe Sylve
df2b2eb63d runtime: improve last ditch signal forwarding for Unix libraries
The current runtime attempts to forward signals generated by non-Go
code to the original signal handler.  If it can't call the original
handler directly, it currently attempts to re-raise the signal after
resetting the handler.  In this case, the original context is lost.

This fix prevents that problem by simply returning from the go signal
handler after resetting the original handler.  It only does this when
the original handler is the system default handler, which in all cases
is known to not recover.  The signal is not reset, so it is retriggered
and the original handler takes over with the proper context.

Fixes #14899

Change-Id: Ib1c19dfa4b50d9732d7a453de3784c8141e1cbb3
Reviewed-on: https://go-review.googlesource.com/21006
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2016-03-24 19:34:17 +00:00
Ian Lance Taylor
bac0005ec7 misc/cgo/testcarchive: rewrite test from bash to Go
This is to support https://golang.org/cl/18057, which is going to add
Windows support to this directory.  Better to write the test in Go then
to have both test.bash and test.bat.

Update #13494.

Change-Id: I4af7004416309e885049ee60b9470926282f210d
Reviewed-on: https://go-review.googlesource.com/20892
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
2016-03-23 02:08:49 +00:00
Michael Munday
c16a61515f misc/cgo/test: add RewindAndSetgid implementation for s390x
Required to pass the issue9400 test.

Change-Id: I595223c403b12faade54e2e46510f8537150af39
Reviewed-on: https://go-review.googlesource.com/20940
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2016-03-22 04:34:24 +00:00
Michael Hudson-Doyle
956e9e6c83 cmd/link: do not add duplicate symbols to Allsym
When building shared libraries, all symbols on Allsym are marked reachable.
What I didn't realize was that this includes the ".dup" symbols created when
"dupok" symbols are read from multiple package files. This breaks now because
deadcode makes some assumptions that fail for these ".dup" symbols, but in any
case was a bad idea -- I suspect this change makes libstd.so a bunch smaller,
but creating it was broken before this CL so I can't be sure.

This change simply stops adding these symbols to Allsym, which might make some
of the many iterations over Allsym the linker does a touch quicker, although
that's not the motivation here.

Add a test that no symbols called ".dup" makes it into the runtime shared
library.

Fixes #14841

Change-Id: I65dd6e88d150a770db2d01b75cfe5db5fd4f8d25
Reviewed-on: https://go-review.googlesource.com/20780
Run-TryBot: Michael Hudson-Doyle <michael.hudson@canonical.com>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2016-03-17 01:15:19 +00:00
James Bardin
5a34472d74 cmd/cgo: add C.CBytes
Add a C.CBytes function to copy a Go byte slice into C memory. This
returns an unsafe.Pointer, since that is what needs to be passed to
C.free, and the data is often opaque bytes anyway.

Fixes #14838

Change-Id: Ic7bc29637eb6f1f5ee409b3898c702a59833a85a
Reviewed-on: https://go-review.googlesource.com/20762
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2016-03-16 23:22:10 +00:00
Alex Brainman
03f3bfc460 misc/cgo/test: rewrite windows version of mysleep
Latest version of gcc (tdm-1) 5.1.0 refuses to compile our code
on windows/386 (see issue for details). Rewrite the code.

Fixes #14328

Change-Id: I70f4f063282bd2958cd2175f3974369dd49dd8dc
Reviewed-on: https://go-review.googlesource.com/20008
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2016-03-02 23:33:32 +00:00
Ian Lance Taylor
eaf5235f98 misc/cgo/testsanitizers: don't run tsan tests on old clang
Fixes #14570.

Change-Id: Ief84a14585bfc209e38cdf15702c2f54ba759714
Reviewed-on: https://go-review.googlesource.com/20057
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Michael Hudson-Doyle <michael.hudson@canonical.com>
2016-03-01 00:56:14 +00:00
Ian Lance Taylor
f4717a902e misc/cgo/testsanitizers: test that tsan links
Update #14559.

Change-Id: I92603602e5d0a5fcae43f3084f234ff606447190
Reviewed-on: https://go-review.googlesource.com/20056
Run-TryBot: Ian Lance Taylor <iant@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2016-02-29 17:56:28 +00:00
Ian Lance Taylor
1df5183f4c misc/cgo/testsanitizers: report stderr if go run tsan*.go fails
Update #14559.

Change-Id: I8894f8e16902685f55a21d902199fbe0905f0558
Reviewed-on: https://go-review.googlesource.com/20050
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Dmitry Vyukov <dvyukov@google.com>
2016-02-29 14:58:15 +00:00
Ian Lance Taylor
c8ef0df06c cmd/cgo: add hooks for thread sanitizer
When Go code is used with C code compiled with -fsanitize=thread, adds
thread sanitizer calls so that correctly synchronized Go code does not
cause spurious failure reports from the thread sanitizer.  This may
cause some false negatives, but for the thread sanitizer what is most
important is avoiding false positives.

Change-Id: If670e4a6f2874c7a2be2ff7db8728c6036340a52
Reviewed-on: https://go-review.googlesource.com/17421
Reviewed-by: Dmitry Vyukov <dvyukov@google.com>
2016-02-28 04:56:17 +00:00
kortschak
c86dbbe1b9 misc/cgo/fortran: clean up after successful helloworld.90 build
Change-Id: If03185a21e088c9b383a82c14d649805f00c8042
Reviewed-on: https://go-review.googlesource.com/20000
Reviewed-by: Minux Ma <minux@golang.org>
2016-02-28 04:30:41 +00:00
Ian Lance Taylor
71cc445cf9 cmd/cgo: recognize known C typedefs as types
Fixes #14483.

Change-Id: I0cddfe27fd8d00ba85659d0b618410e39ebf45cb
Reviewed-on: https://go-review.googlesource.com/19860
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
2016-02-27 22:51:51 +00:00
Jeff R. Allen
ee177279a0 misc/cgo: fix wrong quote character
Single quotes to not expand variables inside of them.

Change-Id: I4a0622c0aebfc1c3f9d299f93f7a8253893b5858
Reviewed-on: https://go-review.googlesource.com/13661
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2016-02-26 19:39:51 +00:00
kortschak
a337e30620 cmd/dist: don't run fortran test if fortran compilation fails
Fixes #14498.

Change-Id: I4cfab3e45898466179cefbd31c6f7f796da82363
Reviewed-on: https://go-review.googlesource.com/19874
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2016-02-25 23:52:28 +00:00
kortschak
50c38d46e8 cmd/go, go/build: add support for Fortran
This change adds support for Fortran files (.f, .F, .for, .f90) to the
go tool, in a similar fashion to Objective-C/C++. Only gfortran is
supported out of the box so far but leaves other Fortran compiler
toolchains the ability to pass the correct link options via CGO_LDFLAGS.
A simple test (misc/cgo/fortran) has been added and plugged into the
general test infrastructure. This test is only enabled when the $FC
environment variable is defined (or if 'gfortran' was found in $PATH.)

Derived from CL 4114.

Change-Id: Ifc855091942f95c6e9b17d91c17ceb4eee376408
Reviewed-on: https://go-review.googlesource.com/19670
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2016-02-24 15:06:38 +00:00
Matthew Dempsky
1a94431a78 cmd/cgo: support multiple-value special form in VarDecl
Fixes #13930.

Change-Id: I124b7d31d1f2be05b7f23dafd1e52d9f3f02f3f0
Reviewed-on: https://go-review.googlesource.com/18623
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2016-02-18 20:12:20 +00:00
Ian Lance Taylor
e97096661e runtime: handle kindString in cgoCheckArg
It's awkward to get a string value in cgoCheckArg, but SWIG testing
revealed that it is possible.  The new handling of extra files in the
ptr.go test emulates what SWIG does with an exported function that
returns a string.

Change-Id: I453717f867b8a49499576c28550e7c93053a0cf8
Reviewed-on: https://go-review.googlesource.com/19020
Run-TryBot: Ian Lance Taylor <iant@golang.org>
Reviewed-by: Russ Cox <rsc@golang.org>
2016-01-27 22:50:37 +00:00
Russ Cox
e7ce1ba88c misc/cgo/test: disable sigaltstack test on darwin/386
It doesn't work there ("out of memory") and doesn't really matter.
Fixes build (now that we enable cgo on the darwin/386 builder.)

Change-Id: I1d91e51ecb88c54eae39ac9a76f2c0b4e45263b0
Reviewed-on: https://go-review.googlesource.com/19004
Run-TryBot: Russ Cox <rsc@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
2016-01-27 22:27:05 +00:00
Ian Lance Taylor
1aab7b9626 cmd/link: add -extar option to set ar program for c-archive
People who want to use -buildmode=c-archive in unusual cross-compilation
setups will need something like this.  It could also be done via (yet
another) environment variable but I use -extar by analogy with the
existing -extld.

Change-Id: I354cfabc4c470603affd13cd946997b3a24c0e6c
Reviewed-on: https://go-review.googlesource.com/18913
Reviewed-by: Russ Cox <rsc@golang.org>
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2016-01-26 18:52:36 +00:00
Russ Cox
544f28a25e misc/cgo/test: fix test on darwin/386 with cgo enabled
Apparently the darwin/386 builder does not enable cgo.
This failure turned up running

	GOARCH=386 GOHOSTARCH=386 ./all.bash

on my Mac.

Change-Id: Ia2487c4fd85d4b0f9f564880f22d9fde379946c3
Reviewed-on: https://go-review.googlesource.com/18859
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2016-01-24 20:21:29 +00:00
Michael Hudson-Doyle
cd9fc3ebfb cmd/link: allow symbols from .a files to override those from .so files
https://golang.org/s/execmodes defines rules for how multiple codes of a go
package work when they end up in the address space of a single process, but
currently the linker blows up in this situation. Fix that by loading all .a
files before any .so files and ignoring duplicate symbols found when loading
shared libraries.

I know this is very very late for 1.6 but at least it should clearly not have
any effect when shared libraries are not in use.

Change-Id: I512ac912937e7502ff58eb5628b658ecce3c38e5
Reviewed-on: https://go-review.googlesource.com/18714
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Run-TryBot: Ian Lance Taylor <iant@golang.org>
2016-01-20 19:53:53 +00:00
Joe Sylve
9efc46f1cb cmd/go: -buildmode=c-shared should work on darwin/386
* Enable c-shared buildmode on darwin/386
* dyld does not support text relocation on i386. Add -read_only_relocs suppress flag to linker

Fixes #13904

Change-Id: I9adbd20d3f36ce9bbccf1bffb746b391780d088f
Reviewed-on: https://go-review.googlesource.com/18500
Reviewed-by: David Crawshaw <crawshaw@golang.org>
Reviewed-by: Russ Cox <rsc@golang.org>
2016-01-13 18:24:38 +00:00
Russ Cox
fac8202c3f runtime: make NumGoroutine and Stack agree not to include system goroutines
[Repeat of CL 18343 with build fixes.]

Before, NumGoroutine counted system goroutines and Stack (usually) didn't show them,
which was inconsistent and confusing.

To resolve which way they should be consistent, it seems like

	package main
	import "runtime"
	func main() { println(runtime.NumGoroutine()) }

should print 1 regardless of internal runtime details. Make it so.

Fixes #11706.

Change-Id: If26749fec06aa0ff84311f7941b88d140552e81d
Reviewed-on: https://go-review.googlesource.com/18432
Reviewed-by: Austin Clements <austin@google.com>
Run-TryBot: Russ Cox <rsc@golang.org>
2016-01-13 01:46:01 +00:00
Ian Lance Taylor
21b4f234c7 runtime: for c-archive/c-shared, install signal handlers synchronously
The previous behaviour of installing the signal handlers in a separate
thread meant that Go initialization raced with non-Go initialization if
the non-Go initialization also wanted to install signal handlers.  Make
installing signal handlers synchronous so that the process-wide behavior
is predictable.

Update #9896.

Change-Id: Ice24299877ec46f8518b072a381932d273096a32
Reviewed-on: https://go-review.googlesource.com/18150
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: David Crawshaw <crawshaw@golang.org>
2016-01-09 00:58:38 +00:00
Ian Lance Taylor
d91ec5bb40 cmd/cgo, runtime: recognize unsafe.Pointer(&s[0]) in cgo pointer checks
It's fairly common to call cgo functions with conversions to
unsafe.Pointer or other C types.  Apply the simpler checking of address
expressions when possible when the address expression occurs within a
type conversion.

Change-Id: I5187d4eb4d27a6542621c396cad9ee4b8647d1cd
Reviewed-on: https://go-review.googlesource.com/18391
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Russ Cox <rsc@golang.org>
2016-01-08 03:56:30 +00:00
Ian Lance Taylor
2586af47f6 misc/cgo/testcarchive,testcshared: deflake tests
After a failure on the build dashboard I tested testcarchive test 2 and
found that it failed an average of 1 in 475 runs on my laptop.  With
this change it ran over 50,000 times without failing.  I bumped up the
other iteration limits to correspond.

Change-Id: I0155c68161a2c2a09ae25c91e9269f1e8702628d
Reviewed-on: https://go-review.googlesource.com/18309
Run-TryBot: Ian Lance Taylor <iant@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2016-01-07 01:32:29 +00:00
Ian Lance Taylor
a7cad52e04 runtime: preserve signal stack when calling Go on C thread
When calling a Go function on a C thread, if the C thread already has an
alternate signal stack, use that signal stack instead of installing a
new one.

Update #9896.

Change-Id: I62aa3a6a4a1dc4040fca050757299c8e6736987c
Reviewed-on: https://go-review.googlesource.com/18108
Reviewed-by: Russ Cox <rsc@golang.org>
2016-01-06 23:11:42 +00:00
Ian Lance Taylor
934e055f41 runtime: call msanwrite on object passed to runtime/cgo
Avoids an msan error when runtime/cgo is explicitly rebuilt with
-fsanitize=memory.

Fixes #13815.

Change-Id: I70308034011fb308b63585bcd40b0d1e62ec93ef
Reviewed-on: https://go-review.googlesource.com/18263
Reviewed-by: Russ Cox <rsc@golang.org>
2016-01-06 04:04:42 +00:00
Russ Cox
f2c36df9a2 misc/cgo/testcshared: print a little more about GOROOT on failure
For #13789.

Change-Id: I83973298a35afcf55627f0a72223098306a51f4b
Reviewed-on: https://go-review.googlesource.com/18233
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2016-01-05 14:19:24 +00:00
Ian Lance Taylor
a7d2b4d7ce runtime: disable a signal by restoring the original disposition
Fixes #13034.
Fixes #13042.
Update #9896.

Change-Id: I189f381090223dd07086848aac2d69d2c00d80c4
Reviewed-on: https://go-review.googlesource.com/18062
Reviewed-by: Russ Cox <rsc@golang.org>
2016-01-05 00:25:50 +00:00
Didier Spezia
dc5315c341 build: prevent the entire repo to be wiped out by cgo test scripts
Following the parallelization of some tests, a race condition can
occur in testcarchive, testshared and testcshared.

In some cases, it can result in the go env GOROOT command returning
corrupted data, which are then passed to a rm command.

Make the shell script more robust by not trusting the result of
the go env GOROOT command. It does not really fix the issue, but
at least prevent the entire repository to be deleted.

Updates #13789

Change-Id: Iaf04a7bd078ed3a82e724e35c4b86e6f756f2a2f
Reviewed-on: https://go-review.googlesource.com/18173
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Russ Cox <rsc@golang.org>
2016-01-04 19:56:30 +00:00
Dan Peterson
0f3c229030 runtime: fix sigaltstack test Skipf format string
Change-Id: I9485ecbd9d546893e4f0db846b08d835fa7515d7
Reviewed-on: https://go-review.googlesource.com/18140
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
2015-12-24 18:34:18 +00:00
Ian Lance Taylor
f7e51c1320 runtime: adjust gsignal stack to current signal stack
If non-Go code calls sigaltstack before a signal is received, use
sigaltstack to determine the current signal stack and set the gsignal
stack to use it.  This makes the Go runtime more robust in the face of
non-Go code.  We still can't handle a disabled signal stack or a signal
triggered with SA_ONSTACK clear, but we now give clear errors for those
cases.

Fixes #7227.
Update #9896.

Change-Id: Icb1607e01fd6461019b6d77d940e59b3aed4d258
Reviewed-on: https://go-review.googlesource.com/18102
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Mikio Hara <mikioh.mikioh@gmail.com>
2015-12-24 17:00:04 +00:00
Ian Lance Taylor
94ff47939a misc/cgo/testcarchive: skip test4 on darwin/{arm,arm64}
Fixes #13701.

Change-Id: I9825864d23aeba1971cf5f581e1e59ac4c9b87fd
Reviewed-on: https://go-review.googlesource.com/18090
Reviewed-by: David Crawshaw <crawshaw@golang.org>
2015-12-22 16:16:02 +00:00
Ian Lance Taylor
fbdfa99246 runtime: for c-archive/c-shared, don't install unnecessary signal handlers
Only install signal handlers for synchronous signals that become
run-time panics.  Set the SA_ONSTACK flag for other signal handlers as
needed.

Fixes #13028.
Update #12465.
Update #13034.
Update #13042.

Change-Id: I28375e70641f60630e10f3c86e24b6e4f8a35cc9
Reviewed-on: https://go-review.googlesource.com/17903
Reviewed-by: Russ Cox <rsc@golang.org>
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2015-12-18 22:27:38 +00:00
Shenghou Ma
a766d8e59c cmd/cgo: map C unsigned char back to _Ctype_uchar in error messages
Fixes #13635.

Change-Id: Icab4a45567f435f002a8f6c85db9538acf054a70
Reviewed-on: https://go-review.googlesource.com/17863
Run-TryBot: Minux Ma <minux@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2015-12-16 22:13:17 +00:00
Ian Lance Taylor
dcc821faf8 misc/cgo/gmp: change pi.go to use standard Go copyright header
This file is not part of the benchmark shootout, and we wrote it, so use
the usual copyright header, not a partial version of the shootout
license.

Fixes #13575.

Change-Id: Ib610e2ad82914b4ef096a2424cfffe3383db2d5b
Reviewed-on: https://go-review.googlesource.com/17715
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Russ Cox <rsc@golang.org>
2015-12-11 13:29:46 +00:00
Russ Cox
05390a0793 misc/cgo/stdio: reenable tests
The build tags are necessary to keep "go build" in that directory
building only stdio.go, but we have to arrange for test/run.go to
treat them as satisfied.

Fixes #12625.

Change-Id: Iec0cb2fdc2c9b24a4e0530be25e940aa0cc9552e
Reviewed-on: https://go-review.googlesource.com/17454
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2015-12-05 21:24:30 +00:00
Russ Cox
b5e2ec8bbe misc/cgo/testcshared: use fd 100 instead of fd 10 for back-channel communication
There is a report that fd 10 is already in use when run on some OS X machines.
I don't see how, and I can't reproduce the problem on my own OS X machine,
but it's easy enough to fix.

Fixes #12161.

Change-Id: I73511bdd91258ecda181d60d2829add746d1198b
Reviewed-on: https://go-review.googlesource.com/17451
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2015-12-05 03:56:23 +00:00
Mohit Agarwal
70d558be8f misc/cgo/testsanitizers: check linux major/minor versions
Fix a typo in de5b386; using `$ver` to determine linux major/minor
versions would produce those for clang, use `$linuxver` instead.

Updates #12898.

Change-Id: I2c8e84ad02749fceaa958afd65e558bb0b08dddb
Reviewed-on: https://go-review.googlesource.com/17323
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2015-12-03 21:22:27 +00:00
Russ Cox
de5b386157 misc/cgo/testsanitizers: do not run with clang < 3.8 and Linux ≥ 4.1
These are simply incompatible. Clang fixed the bug but not in older versions.

Fixes #12898.

Change-Id: I74a3fd9134dadab6d0f074f8fd09e00d64558d7a
Reviewed-on: https://go-review.googlesource.com/17254
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2015-12-03 14:48:46 +00:00
Ian Lance Taylor
5a049aa4a6 cmd/cgo: error, not panic, if not enough arguments to function
Fixes #13423.

Change-Id: I41bb45790cca36c57a107796f0eca61287acb2a9
Reviewed-on: https://go-review.googlesource.com/17332
Run-TryBot: Ian Lance Taylor <iant@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2015-12-02 21:02:28 +00:00
Ian Lance Taylor
17360accab cmd/cgo: make the char * pointer in GoString const
This makes it more convenient for C code to use GoString with string
constants.  Since Go string values are immutable, the const qualifier is
appropriate in C.

Change-Id: I5fb3cdce2ce5079f1f0467a1544bb3a1eb27b811
Reviewed-on: https://go-review.googlesource.com/17067
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Russ Cox <rsc@golang.org>
2015-11-29 16:55:40 +00:00
Matthew Dempsky
10cb39afc4 cmd/cgo: fix C.complexfloat and C.complexdouble
This also fixes an unintended behavior where C's "complex float" and
"complex double" types were interchangeable with Go's "complex64" and
"complex128" types.

Fixes #13402.

Change-Id: I73f96d9a4772088d495073783c6982e9634430e8
Reviewed-on: https://go-review.googlesource.com/17208
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2015-11-25 23:06:59 +00:00
Matthew Dempsky
de640d369d cmd/cgo: handle another Clang DWARF quirk
Without the fix:

    $ CC=clang-3.5 ./test.bash
    misc/cgo/errors/test.bash: BUG: expected error output to contain "C.ushort" but saw:
    # command-line-arguments
    ./issue13129.go:13: cannot use int(0) (type int) as type C.unsignedshort in assignment

Fixes #13129.

Change-Id: I2c019d2d000f5bfa3e33c477e533aff97031a84f
Reviewed-on: https://go-review.googlesource.com/17207
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2015-11-25 21:13:41 +00:00
Ian Lance Taylor
0417872809 cmd/cgo: ignore vars with no name or type if they have a AttrSpecification
Fixes #13344.

Change-Id: I33c6721fd33d144c85c87840ddf27ce15aa72328
Reviewed-on: https://go-review.googlesource.com/17151
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Minux Ma <minux@golang.org>
2015-11-23 04:04:07 +00:00
Mohit Agarwal
54bd5a71d3 misc/cgo/testshared: add format specifier in Errorf calls
Found by cmd/vet

Change-Id: I29dd207ecd40fe703054e8ad4e81b3267ca89da2
Reviewed-on: https://go-review.googlesource.com/17160
Reviewed-by: David Crawshaw <crawshaw@golang.org>
2015-11-21 10:19:16 +00:00
Ian Lance Taylor
5005a33987 cmd/cgo: put the real C function in the dynamic symbol table
In the past, cgo generated Go code and C code.  The C code was linked
into a shared library.  The Go code was built into an executable that
dynamically linked against that shared library.  C wrappers were
exported from the shared library, and the Go code called them.

It was all a long time ago, but in order to permit C code to call back
into Go, somebody implemented #pragma dynexport (https://golang.org/cl/661043)
to export a Go symbol into the dynamic symbol table.  Then that same
person added code to cgo to recognize //export comments
(https://golang.org/cl/853042).  The //export comments were implemented
by generating C code, to be compiled by GCC, that would refer to C code,
to be compiled by 6c, that would call the Go code.  The GCC code would
go into a shared library.  The code compiled by 6c would be in the Go
executable.  The GCC code needed to refer to the 6c code, so the 6c
function was marked with #pragma dynexport.  The important point here is
that #pragma dynexport was used to expose an internal detail of the
implementation of an exported function, because at the time it was
necessary.

Moving forward to today, cgo no longer generates a shared library and 6c
no longer exists.  It's still true that we have a function compiled by
GCC that refers to a wrapper function now written in Go.  In the normal
case today we are doing an external link, and we use a
//go:cgo_export_static function to make the Go wrapper function visible
to the C code under a known name.

The #pragma dynexport statement has become a //go:cgo_export_dynamic
comment on the Go code.  That comment only takes effect when doing
internal linking.  The comment tells the linker to put the symbol in the
dynamic symbol table.  That still makes sense for the now unusual case
of using internal linking with a shared library.

However, all the changes to this code have carefully preserved the
property that the //go:cgo_export_dynamic comment refers to an internal
detail of the implementation of an exported function.  That was
necessary a long time ago, but no longer makes sense.

This CL changes the code to put the actual C-callable function into the
dynamic symbol table.  I considered dropping the comment entirely, but
it turns out that there is even a test for this, so I preserved it.

Change-Id: I66a7958e366e5974363099bfaa6ba862ca327849
Reviewed-on: https://go-review.googlesource.com/17061
Run-TryBot: Ian Lance Taylor <iant@golang.org>
Reviewed-by: Minux Ma <minux@golang.org>
2015-11-20 00:19:07 +00:00