This is the mail archive of the
libc-alpha@sourceware.org
mailing list for the glibc project.
Re: [PATCH][BZ #19490] Add unwind descriptors for x86_64 _mcount and __fentry__
- From: "H.J. Lu" <hjl dot tools at gmail dot com>
- To: Paul Pluzhnikov <ppluzhnikov at google dot com>
- Cc: Andreas Schwab <schwab at suse dot de>, GLIBC Devel <libc-alpha at sourceware dot org>, Andi Kleen <andi at firstfloor dot org>
- Date: Thu, 3 Mar 2016 09:30:41 -0800
- Subject: Re: [PATCH][BZ #19490] Add unwind descriptors for x86_64 _mcount and __fentry__
- Authentication-results: sourceware.org; auth=none
- References: <CALoOobPzA=QaRyua2KVLR5CtKoks_Tz=c45SwWBg18sY0X4kWg at mail dot gmail dot com> <20160222091457 dot GJ19841 at vapier dot lan> <CALoOobMWtqPyM99G4mX56nV=ymqNGFKEwWMAmc0h_Uff_K2yjA at mail dot gmail dot com> <20160226034043 dot GM19841 at vapier dot lan> <CALoOobMtV8tWzW5rxU-UUN0Q7Pc3TCVUpfXXr3kOUoodr+0n0w at mail dot gmail dot com> <CAMe9rOpAgpdPTPz7ac_kyfkCG19YQwQTyhQzPRWuN8BEg5aS-Q at mail dot gmail dot com> <CALoOobOYv1i+D41VOECjQtyKeDF3LBGdT=z37gH3zMEJ=jctQQ at mail dot gmail dot com> <mvmio14neuh dot fsf at hawking dot suse dot de> <CALoOobMRss18H48kOngTdyXWO1tJf=YahxqJavLyuZcXQVzW8g at mail dot gmail dot com>
On Thu, Mar 3, 2016 at 9:01 AM, Paul Pluzhnikov <ppluzhnikov@google.com> wrote:
> On Thu, Mar 3, 2016 at 12:30 AM, Andreas Schwab <schwab@suse.de> wrote:
>> Paul Pluzhnikov <ppluzhnikov@google.com> writes:
>>
>>> Using CALL_MCOUNT in implementation of _mcount isn't going to end well.
>>
>> _mcount needs to be arranged to be compiled without PROF, like the
>> noprof routines in gmon/Makefile.
>
> Done by HJ in commit 87a07a437656aede6f303688b55ae1834962bee2.
>
> Updated patch attached. Tested on Linux/x86_64.
>
> Thanks,
>
> 2016-03-03 Paul Pluzhnikov <ppluzhnikov@google.com>
>
> [BZ #19490]
> * sysdeps/x86_64/_mcount.S (_mcount): Add unwind descriptor.
> (__fentry__): Likewise
>
Hi Andi,
Why do we need __fentry__ different from _mcount in glibc? Can we
make __fentry__ an alias of _mcount?
--
H.J.