This is the mail archive of the
libc-alpha@sourceware.org
mailing list for the glibc project.
Re: The time(2) man page conflicts with glibc
- From: Andreas Schwab <schwab at suse dot de>
- To: Zack Weinberg <zackw at panix dot com>
- Cc: GNU C Library <libc-alpha at sourceware dot org>
- Date: Tue, 15 Dec 2015 16:12:03 +0100
- Subject: Re: The time(2) man page conflicts with glibc
- Authentication-results: sourceware.org; auth=none
- References: <CAMe9rOoJLk8VzyJKmkOvbmBxhCj4mVA2huYtHJsdxpatbkgJ1g at mail dot gmail dot com> <CAKCAbMj-X+wLKX3=MDm9z3L9zyikemxCNggu2bfw6=o6K5PGgg at mail dot gmail dot com> <mvm7fkf941w dot fsf at hawking dot suse dot de> <CAKCAbMj-nskJ2M2i2mRn+2Cdv59r5JdrKk3_et8=Ne_Oe29wwA at mail dot gmail dot com>
Zack Weinberg <zackw@panix.com> writes:
> On Tue, Dec 15, 2015 at 9:31 AM, Andreas Schwab <schwab@suse.de> wrote:
>> Zack Weinberg <zackw@panix.com> writes:
>>
>>> I did. The *actual system call* does indeed return -EFAULT when
>>> memory is invalid, which will be observed as 0xfffffffffffffff2 in the
>>> return value. However, the *vDSO shortcut* (which does not trap into
>>> the kernel) will just segfault the application. This is an observable
>>> ABI difference between statically and dynamically linked binaries.
>>
>> Undefined behaviour can change any time in any way and is not part of
>> the ABI.
>
> I should have said "observable behavior difference".
It doesn't matter.
Andreas.
--
Andreas Schwab, SUSE Labs, schwab@suse.de
GPG Key fingerprint = 0196 BAD8 1CE9 1970 F4BE 1748 E4D4 88E3 0EEA B9D7
"And now for something completely different."