From: Arnaldo Carvalho de Melo <acme-wEGCiKHe2LqWVfeAwA7xHQ@public.gmane.org>
To: Nicolas <nikos42-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>
Cc: dwarves-u79uwXL29TY76Z2rM5mHXA@public.gmane.org
Subject: Re: Brain fart alert
Date: Mon, 20 Aug 2012 15:28:10 -0300 [thread overview]
Message-ID: <20120820182810.GF3046@infradead.org> (raw)
In-Reply-To: <20120820180216.GE3046-wEGCiKHe2LqWVfeAwA7xHQ@public.gmane.org>
Em Mon, Aug 20, 2012 at 03:02:16PM -0300, Arnaldo Carvalho de Melo escreveu:
> Em Sat, Jul 21, 2012 at 08:22:33PM +0200, Nicolas escreveu:
> > I tried using pahole, but I get a brain fart alert with the file
> > attached (which is an extract from stdio.h). I'm running dwarves 1.10,
> > libdw1 0.152 and g++ 4.6.1, on i386.
> >
> > Here is what I get:
> >
> > $ g++ -Wall -g -c brainfart.cpp -o brainfart.o && pahole brainfart.o
> > class ios_base {
> > enum _Ios_Openmodeconst in; /* 0 4 */
> > typedef enum _Ios_Fmtflags fmtflags;
> >
> > /* size: 1, cachelines: 1, members: 1 */
> > /* padding: 65533 */
> > /* last cacheline: 1 bytes */
> >
> > /* BRAIN FART ALERT! 1 != 4 + 0(holes), diff = -3 */
>
> Can you please clone my git tree and try it from there?
>
> git clone git://git.kernel.org/pub/scm/devel/pahole/pahole
> cd pahole
> mkdir build
> cd build
> cmake ..
> cd ..
> make -C build
> build/pahole brainfart.o
>
> Now I'm getting:
>
> [acme@sandy pahole]$ build/pahole brainfart.o
> class ios_base {
> static enum _Ios_Openmodeconst in = 8; /* 0 0 */
> typedef enum _Ios_Fmtflags fmtflags;
>
>
> /* size: 1, cachelines: 0, members: 0, static members: 1 */
> /* last cacheline: 1 bytes */
> };
> [acme@sandy pahole]$
>
> I still need to get the 'const' there, from the fact that it has a
> DW_AT_const_value, that is already captured, just forgot to add the
> 'const' there, will do after some errands here.
>
> Also I'll check that the member type is an enum, will lookup the
> enumerator entry that has the DW_AT_const_value and replace that '8'
> with it.
I also noticed that there is a problem when the static member is not the
first, related to bitfield hole detection, will fix it too.
- Arnaldo
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next prev parent reply other threads:[~2012-08-20 18:28 UTC|newest]
Thread overview: 20+ messages / expand[flat|nested] mbox.gz Atom feed top
2012-07-21 18:22 Brain fart alert Nicolas
[not found] ` <CACHCVZ6oDyFwGbC4EwF_wsR9tCkoych5N6buLhRRLcyaL6iifw-JsoAwUIsXosN+BqQ9rBEUg@public.gmane.org>
2012-08-15 17:56 ` Arnaldo Carvalho de Melo
[not found] ` <20120815175647.GK2370-wEGCiKHe2LqWVfeAwA7xHQ@public.gmane.org>
2012-08-16 19:52 ` Arnaldo Carvalho de Melo
[not found] ` <20120816195224.GC10277-wEGCiKHe2LqWVfeAwA7xHQ@public.gmane.org>
2012-08-19 22:16 ` Mark Wielaard
2012-08-20 13:45 ` Dodji Seketeli
[not found] ` <m3obm5fzhs.fsf-fIDRvF7C5exg9hUCZPvPmw@public.gmane.org>
2012-08-20 17:35 ` Arnaldo Carvalho de Melo
2012-08-20 18:02 ` Arnaldo Carvalho de Melo
[not found] ` <20120820180216.GE3046-wEGCiKHe2LqWVfeAwA7xHQ@public.gmane.org>
2012-08-20 18:28 ` Arnaldo Carvalho de Melo [this message]
2012-08-30 16:35 ` Nicolas
[not found] ` <CACHCVZ5EJadxOTJ0T4phSfAcm1FK7wfeDTp9QcSa1V1JCpa8SA-JsoAwUIsXosN+BqQ9rBEUg@public.gmane.org>
2012-09-03 12:22 ` Mark Wielaard
[not found] ` <1346674948.3090.40.camel-OO0OHOuVXW89n/EXqpbZ8ns8WZQLr0HW@public.gmane.org>
2012-09-24 22:19 ` Nicolas
[not found] ` <5060DC56.4080609-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>
2013-02-26 1:50 ` Nicolas
[not found] ` <CACHCVZ6uvDW1CpyxXio3P17EL6bE=FKGDNm11RNZTceR-dWLjg-JsoAwUIsXosN+BqQ9rBEUg@public.gmane.org>
2013-02-26 10:56 ` Mark Wielaard
[not found] ` <1361876163.4930.4.camel-Et2QWsRS+g7yukXOleVwRPp4M6BF03vq@public.gmane.org>
2013-03-20 13:37 ` Arnaldo Carvalho de Melo
2015-11-11 18:26 David Sterba
[not found] ` <20151111182618.GF6445-AlSwsSmVLrQ@public.gmane.org>
2015-11-11 20:11 ` Arnaldo Carvalho de Melo
[not found] ` <20151111201151.GA6712-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org>
2015-11-11 21:05 ` David Sterba
[not found] ` <20151111210519.GG6445-AlSwsSmVLrQ@public.gmane.org>
2015-11-11 22:13 ` Arnaldo Carvalho de Melo
[not found] ` <20151111221340.GB12579-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org>
2015-11-11 22:17 ` Arnaldo Carvalho de Melo
[not found] ` <20151111221747.GC12579-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org>
2015-11-11 22:48 ` Arnaldo Carvalho de Melo
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