Start address of a binary

Start address of a binary

[Sébastien Côté]

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Hi,

I recently built a cross-compiler for Powerpc running in little-endian. 
The compiler seems to work fine since the kernel runs until I load my first
binary (init).

I compiled my init with he same cross-compiler but when the linker comes in
I get:
ld : warning: cannot find entry symbol _start; defaulting to 0180074

Is 0x180074 right?  I know this is a virtual address but I tought it should
be something like 0x10000000.  Is there a problem with my compiler or my
linker?


Thanks!

Sébastien Côté

Re: Start address of a binary

[Alexandre Oliva]

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On Feb 20, 2001, Sébastien Côté <scote1@Matrox.COM> wrote:

> ld : warning: cannot find entry symbol _start; defaulting to 0180074

> Is 0x180074 right?

It may be.  If no _start symbol exists in the executable, the linker
probably assumes it should start in the beginning of the .text
section.  But you'd better define _start properly so that it calls
global initializers, then main().

-- 
Alexandre Oliva   Enjoy Guarana', see http://www.ic.unicamp.br/~oliva/
Red Hat GCC Developer                  aoliva@{cygnus.com, redhat.com}
CS PhD student at IC-Unicamp        oliva@{lsd.ic.unicamp.br, gnu.org}
Free Software Evangelist    *Please* write to mailing lists, not to me

Re: Start address of a binary

[Sébastien Côté]

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Alexandre Oliva wrote:
> 
> On Feb 20, 2001, Sébastien Côté <scote1@Matrox.COM> wrote:
> 
> > ld : warning: cannot find entry symbol _start; defaulting to 0180074
> 
> > Is 0x180074 right?
> 
> It may be.  If no _start symbol exists in the executable, the linker
> probably assumes it should start in the beginning of the .text
> section.  But you'd better define _start properly so that it calls
> global initializers, then main().

Looking at the objdump of the file, the instructions seems to be right. 
I'm more suspicious about the address because my frind's compiler
defaults to 0x10000074 (why this difference, I couldn't tell).

I defined _start just to be sure and the first addres was still
0x180074.  Can it be any value or does it have to be within a range?

Thanks for your help,

Sébastien Côté