From: yunfeng zhang <zyf.zeroos@gmail.com>
To: gcc@gcc.gnu.org
Cc: Richard Henderson <rth@redhat.com>, Andrew Haley <aph@redhat.com>
Subject: Re: No .got section in ELF
Date: Thu, 26 Nov 2009 02:24:00 -0000 [thread overview]
Message-ID: <4df04b840911251824j71fa1d33i2cecc9481617dda5@mail.gmail.com> (raw)
In-Reply-To: <4df04b840911231758md5a545el2d417b663af1647f@mail.gmail.com>
It seems that original limitation isn't clear or sufficient
For a sample:
// f.c
int g;
void foo(void)
{
g = 1;
}
compile with `gcc -shared -fPIC -Wl,-soname,f.so,-Map,f.map -o f.so f.c',
according to f.map, offsetof(g - foo) in library is 0x1550 - 0x3cc = 0x1184,
however let's load the library to memory, offsetof(g - foo) in memory is
0x2c2550 - 0x2c13cc = 0x1184. That's the key of my idea!
Target OS need support --segment-model=elf-layout. In fact, Linux only simply
maps the library to memory, using segment model *defined* in ELF!
So as the previous mail, offsetof(C - A) is const!
next prev parent reply other threads:[~2009-11-26 2:24 UTC|newest]
Thread overview: 17+ messages / expand[flat|nested] mbox.gz Atom feed top
2009-11-24 1:58 yunfeng zhang
2009-11-24 10:00 ` Andrew Haley
2009-11-24 17:10 ` Richard Henderson
2009-11-26 2:24 ` yunfeng zhang [this message]
2009-11-26 3:11 ` Richard Henderson
2009-11-26 6:04 ` yunfeng zhang
2009-11-26 7:55 ` Alexandre Oliva
2009-11-27 2:18 ` yunfeng zhang
2009-11-27 4:12 ` Dave Korn
2009-11-27 4:43 ` yunfeng zhang
2009-11-27 4:46 ` Dave Korn
2009-11-27 13:35 ` Alexandre Oliva
2009-11-30 11:10 ` Yunfeng ZHANG
2009-11-27 4:58 ` Jie Zhang
2009-11-27 6:42 ` yunfeng zhang
2009-11-27 14:16 ` Ian Lance Taylor
2009-11-27 4:51 Dmitry Gorbachev
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