From: Florian Weimer <fweimer@redhat.com>
To: Joseph Myers <joseph@codesourcery.com>
Cc: libc-alpha@sourceware.org
Subject: Re: [PATCH] malloc: Deprecate hook variables, __default_morecore, <mcheck.h>
Date: Tue, 15 Nov 2016 15:56:00 -0000 [thread overview]
Message-ID: <bea209cf-2ba3-8414-478c-5d643907341e@redhat.com> (raw)
In-Reply-To: <alpine.DEB.2.20.1611151523490.6705@digraph.polyomino.org.uk>
On 11/15/2016 04:39 PM, Joseph Myers wrote:
> On Tue, 15 Nov 2016, Florian Weimer wrote:
>
>> In my opinion, the larger ecosystem already provides suitable replacements.
>>
>> * <mcheck.h> and all malloc hook functions are now deprecated. Future
>> implementations of the mcheck- and mtrace-related functions will not
>> have any effect, and glibc will stop calling the hook functions from
>> its malloc implementation. Instead of mcheck and mtrace, developers
>> should consider using valgrind. As a replacement for the hook
>> functions, developers can interpose their own malloc implementation.
>
> I don't consider valgrind suitable for replacing the uses of mtrace in the
> glibc testsuite (or other similar uses elsewhere for lightweight checking
> for leaks).
I completely agree.
The above is for the NEWS file, for external use. For internal use, we
still need a solution. (I have an mtrace-compatible interposition-based
tracer almost finished, but it may not make the cut for the next
release, and it may be superseded by DJ's work anyway.) I think we can
run internal deprecation at a different pace than external deprecation.
> I don't know enough about the functionality GDB expects from linking with
> -lmcheck by default in development to know whether other malloc
> improvements would provide similar checking by default or whether that
> would also need GDB to provide its own malloc (again, I think valgrind is
> vastly too heavyweight for using by default in GDB development).
I wasn't aware that GDB developers are using this functionality. I'll
ask them how critical it is to their needs. But I expect that there
will be no glibc release which neither provides mcheck, nor provides an
alternative.
Thanks,
Florian
next prev parent reply other threads:[~2016-11-15 15:56 UTC|newest]
Thread overview: 15+ messages / expand[flat|nested] mbox.gz Atom feed top
2016-10-26 15:02 Florian Weimer
2016-10-26 15:55 ` Joseph Myers
2016-11-15 13:22 ` Florian Weimer
2016-11-15 15:39 ` Joseph Myers
2016-11-15 15:56 ` Florian Weimer [this message]
2016-11-16 1:37 ` Joseph Myers
2016-11-16 9:46 ` Will Newton
2016-11-17 13:00 ` Florian Weimer
2016-11-17 14:27 ` Joseph Myers
2016-11-17 14:50 ` Steve Vormwald
2016-11-17 16:08 ` Adhemerval Zanella
2016-11-18 9:13 ` Florian Weimer
2016-11-18 17:29 ` Steve Vormwald
2016-11-21 19:43 ` DJ Delorie
2016-11-22 15:12 ` Florian Weimer
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