This is the mail archive of the cygwin mailing list for the Cygwin project.


Index Nav: [Date Index] [Subject Index] [Author Index] [Thread Index]
Message Nav: [Date Prev] [Date Next] [Thread Prev] [Thread Next]
Other format: [Raw text]

Re: Use of Dual Core causes random failures building OpenJDK


On Fri, Nov 20, 2009 at 01:19:57PM -0500, mike marchywka wrote:
>On 11/20/09, Corinna Vinschen  wrote:
>> On Nov 20 09:32, Christopher Faylor wrote:
>>> On Fri, Nov 20, 2009 at 12:20:52PM +0100, Corinna Vinschen wrote:
>>> >On Nov 20 06:04, mike marchywka wrote:
>>> >> On 11/19/09, Larry Hall (Cygwin) <reply-to-list-only-lh@cygwin.com>
>>> >> wrote:
>>> >>>Wow! I had a hunch that BLODA could be the cause of the file related
>>> >>>problems but it never occurred to me that it could be screwing up
>>> >>>environment variables too.
>>> >>
>>> >>Anyone care to determine if env updates are not thread safe?
>>> >
>>> >It's indeed not thread safe.  Looks like we need some locking...
>>>
>>> What's "it" in this case?  putenv?
>>
>> "it" is primarily _addenv, which is used by setenv and putenv.
>>
>>>   The putenv() function is not required to be reentrant, and the one in
>>>   libc4, libc5 and glibc 2.0 is not, but the glibc 2.1 version is
>>
>> Same for setenv and unsetenv, which don't need to be thread-safe per
>> POSIX.  glibc's setenv is thread-safe, though.
>>
>>> I agree that it would be nice to make it safer but is there really code
>>> here which is updating the environment in separate threads?
>>
>> And given POSIX, if so, it would be an application bug if the application
>> doesn't care by itself to use setenv/getenv in a thread-safe manner.
>
>Why does the OS let this happen?  I thought windoze should avoid
>garbage.

Er, I think you're a little confused about what we're talking about.  The
OS doesn't enforce thread safety.  There's really no way that it can.

cgf

--
Problem reports:       http://cygwin.com/problems.html
FAQ:                   http://cygwin.com/faq/
Documentation:         http://cygwin.com/docs.html
Unsubscribe info:      http://cygwin.com/ml/#unsubscribe-simple


Index Nav: [Date Index] [Subject Index] [Author Index] [Thread Index]
Message Nav: [Date Prev] [Date Next] [Thread Prev] [Thread Next]