Re: Go patch committed: Update libgo to 1.1.1

[Uros Bizjak <ubizjak at gmail dot com>]

On Wed, Jul 24, 2013 at 12:23 AM, Ian Lance Taylor <iant@google.com> wrote:
> On Mon, Jul 22, 2013 at 6:38 AM, Uros Bizjak <ubizjak@gmail.com> wrote:
>>
>>>>>>> I have committed a large patch to update libgo to the library that was
>>>>>>> part of the Go 1.1.1 release.  As usual, I'm not including the entire
>>>>>>> patch in this e-mail message, because it is too large.  I'm only
>>>>>>> including the changes to the files that are partially gccgo-specific.
>>>>>>> Bootstrapped and ran Go testsuite on x86_64-unknown-linux-gnu.
>>>>>>> Committed to mainline and 4.8 branch.
>>>>>>
>>>>>> I have hit following build failure on non-USING_SPLIT_STACK target
>>>>>> (alpha-linux-gnu):
>>>>>
>>>>> Thanks.  Fixed like so.  Committed to mainline and 4.8 branch.
>>>>
>>>> Thanks, with your patch, I was able to compile libgo without problems.
>>>> The testsuite run exposes a timeout in net/http, I am looking into it.
>>
>> I have also managed to trigger the timeout on x86_64-pc-linux-gnu.
>>
>> The test was re-run with GOTESTFLAGS=--keep. When running the
>> resulting a.out with "strace -f -o strace-x86_64 ./a.out" from the
>> saved test directory, the test behaved in the same way as on alpha -
>> it hever finished. I have attached the resulting trace (the test was
>> killed with ctrl-c after some time).
>
> Thanks.  The problematic test is TestLinuxSendfile in
> libgo/net/http/fs_test.go.  That test binary invokes itself using
> strace.  In the trace here, that strace fails:
>
> 8511  ptrace(PTRACE_TRACEME, 0, 0, 0)   = -1 EPERM (Operation not permitted)
> 8511  write(2, "strace: test_ptrace_setoptions_f"..., 96) = 96
>
> The strace is supposed to start up a little server, and the test
> binary tries to connect to that server.  Since the server hasn't
> started, the test times out.
>
> The strace invocation is
>
> strace -f -q -e trace=sendfile,sendfile64 ./a.out
> -test.run=TestLinuxSendfileChild
>
> Any idea why that would fail?

Manual invocation of this command tells us the reason. On alpha, it says:

$ strace -f -e trace=sendfile64 ./a.out
strace: invalid system call 'sendfile64'

> The Alpha stack trace you send also indicates a failure in this test.
> It could be for the same reason; hard to say.  The Alpha strace output
> you send doesn't tell me much, since it wasn't done with -f.

I have resent you the strace. The important part is:

7407  write(2, "strace: invalid system call 'sen"..., 41 <unfinished ...>
7405  <... sigreturn resumed> )         = -1
7407  <... write resumed> )             = 41
7405  osf_sigprocmask(SIG_BLOCK, [] <unfinished ...>
7407  exit_group(1)                     = ?
7405  <... osf_sigprocmask resumed> )   = 0 (old mask [])
7405  connect(7, {sa_family=AF_INET, sin_port=htons(32998),
sin_addr=inet_addr("127.0.0.1")}, 16) = 0
7407  +++ exited with 1 +++

The child exited with error, but this is not handled in the test, and
the test waits for dead process indefinitely.

I think that the test should detect, if test system supports
sendfile64 and perhaps also handle invocation failure from the child
process.

Thanks,
Uros.