ld error

ld error

[G Anna]

Dear All,

I am working through 'Linux Assembly "Hello World" Tutorial, CS 200'
by Bjorn Chambless.  But I am unable to compile the program given in
that.  Kindly help me. 

For your convenience I have included the assembly program at the end
of this mail.

average.s is the relevant assembly program file.

$ as -a --gstabs -o average.o average.s

$ ld -m elf_i386 -static /usr/lib/crt1.o /usr/lib/crti.o -lc average.o
                              /usr/lib/crtn.o

/usr/lib/libc.a(strtoll.o): In function `__strtoll_internal':
/usr/src/bs/BUILD/glibc-2.2.2/stdlib/../sysdeps/generic/strtol.c:386: undefined reference to `__udivdi3'
/usr/src/bs/BUILD/glibc-2.2.2/stdlib/../sysdeps/generic/strtol.c:387: undefined reference to `__umoddi3'
/usr/lib/libc.a(strtoull.o): In function `__strtoull_internal':
/usr/src/bs/BUILD/glibc-2.2.2/stdlib/../sysdeps/generic/strtol.c:386: undefined reference to `__udivdi3'
/usr/src/bs/BUILD/glibc-2.2.2/stdlib/../sysdeps/generic/strtol.c:387: undefined reference to `__umoddi3'

$ cat average.s
.data   

	.type hi_temp,@object  
        .size hi_temp,1       
hi_temp:
        .byte 0x92      

        .type lo_temp,@object
        .size lo_temp,1
lo_temp:
        .byte 0x52

        .type av_temp,@object
        .size av_temp,1
av_temp:
        .byte 0

.text
        .align 4        
.globl main            
        .type main,@function    

main:
        pushl %ebp      
        movl %esp,%ebp 
        movb hi_temp,%al
        addb lo_temp,%al
        movb $0,%ah
        adcb $0,%ah
        movb $2,%bl
        idivb %bl
        movb %al,av_temp
        leave           
        ret            

$ as --version
GNU assembler 2.10.91
Copyright 2001 Free Software Foundation, Inc.
This program is free software; you may redistribute it under the terms of
the GNU General Public License.  This program has absolutely no warranty.
This assembler was configured for a target of `i386-redhat-linux'.

$ ld --version
GNU ld 2.10.91
Copyright 2001 Free Software Foundation, Inc.
This program is free software; you may redistribute it under the terms of
the GNU General Public License.  This program has absolutely no warranty.
  Supported emulations:
   elf_i386
   i386linux
   elf_i386_glibc21

$ gcc --version
2.96

$ uname -a
Linux wobble 2.4.16 #8 Tue May 14 14:15:58 IST 2002 i686 unknown

$ cat /etc/issue

Red Hat Linux release 7.1 (Seawolf)
Kernel 2.4.16 on an i686

Hope somebody will help me with this.

Thank you.

Cheers,
anna

-- 

(15) I will never employ any device with a digital countdown. If I find
     that  such  a  device  is absolutely unavoidable, I will set it to
     activate when the counter reaches 117 and the hero is just putting
     his plan into operation. - Peter Anspach in "The Top 100 Things 
     I'd Do If I Ever Became An Evil Overlord"

                                            http://www.eviloverlord.com

Re: ld error

[Alfred Cleve]

Hi,

> I am working through 'Linux Assembly "Hello World" Tutorial, CS 200'
> by Bjorn Chambless.  But I am unable to compile the program given in
> that.  Kindly help me.

i suspect that exercise isn't a simple "hello world"-program. It seems to me 
as a nasty trap for lazy students :-))

The module "average" is a subroutine e.g. a "function" which should be linked 
to a given C-Program.

For my first step i'm looking for a readable tutorial to the "gas"-assembler.

Have you seen anything in the web ?

Thanks,
Alfred


-- 
Alfred Cleve
Karbener Str. 7
61130 Nidderau-Heldenbergen
Germany
Phone +49-6187-901095

Re: ld error

[Emmet Ford]

 > a readable tutorial to the "gas"-assembler.

You wander along a lightly trodden path. Here is what I have...

Linux Assembly Tutorial (nice)
http://www.geocities.com/SiliconValley/Ridge/2544/asm/linux-asm.txt

Using Assembly Language in Linux
http://linuxassembly.org/linasm.html

int80h.org -- Unix Assembly Language Programming
http://www.int80h.org/

http://www.gnu.org/manual/gas-2.9.1/as.html
Using as - Table of Contents - GNU Project - Free Software Foundation (FSF)

A Whirlwind Tutorial on Creating Really Teensy ELF Executables for Linux
http://members.tripod.de/linux_progz/docs/teensy.html

Linux 4k intro page
http://ma.verick.co.za/linux4k/

--Emmet Ford



-------- Original Message --------
Subject: Re: ld error
Date: Mon, 27 May 2002 20:27:52 +0200
From: Alfred.Cleve@t-online.de (Alfred Cleve)
To: linux-assembly@vger.kernel.org
References: <m3r8jygir3.fsf@wobble.eth.net>

Hi,

 > I am working through 'Linux Assembly "Hello World" Tutorial, CS 200'
 > by Bjorn Chambless.  But I am unable to compile the program given in
 > that.  Kindly help me.

i suspect that exercise isn't a simple "hello world"-program. It seems 
to me
as a nasty trap for lazy students :-))

The module "average" is a subroutine e.g. a "function" which should be 
linked
to a given C-Program.

For my first step i'm looking for a readable tutorial to the 
"gas"-assembler.

Have you seen anything in the web ?

Thanks,
Alfred


-- 
Alfred Cleve
Karbener Str. 7
61130 Nidderau-Heldenbergen
Germany
Phone +49-6187-901095
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To unsubscribe from this list: send the line "unsubscribe linux-assembly" in
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Re: ld error

[Brian Raiter]

>  > a readable tutorial to the "gas"-assembler.
> 
> You wander along a lightly trodden path. Here is what I have...

[...]

> A Whirlwind Tutorial on Creating Really Teensy ELF Executables for Linux
> http://members.tripod.de/linux_progz/docs/teensy.html

FYI, the proper URL for that document is at:

http://www.muppetlabs.com/~breadbox/software/tiny/teensy.html

Note that the version at that other URL is an older draft, and still
contains some errors that have since been corrected.

Re: ld error

[G Anna]

> Date: Mon, 27 May 2002 20:27:52 +0200
> From: Alfred.Cleve@t-online.de (Alfred Cleve)
> Subj: Re: ld error
> 
> Hi,
> 
> > I am working through 'Linux Assembly "Hello World" Tutorial, CS 200'
> > by Bjorn Chambless.  But I am unable to compile the program given in
> > that.  Kindly help me.
> 
> i suspect that exercise isn't a simple "hello world"-program. It
> seems to me as a nasty trap for lazy students :-))
> 
> The module "average" is a subroutine e.g. a "function" which should
> be linked to a given C-Program.

I don't think so, because the given assembly program has a main
function; and the tutorial has given a step by step procedure to
produce the executable.  

Inspite of my above statement, I am not very sure of the given
assembly program being complete, basically because it doesn't work!
But it does have a main function.

[ Added as an after-thought: Doesn't the function named 'main' have
any special significance in assembly language programs? ]

(begin-quote)

/* segment registers set up by linked code */
/* beginning of text(code) segment */
.text
        .align 4        /* set 4 double-word alignment */
.globl main             /* make main global for linker */
        .type main,@function    /* declare main as a function */
main:
     (definition of main snipped)

(end-quote)

If what you say is correct, then I don't think the tutorial serves its
purpose.  Already, I am pulling my hairs to understand what is going
on, and now I have got to put up with the caveats that the author
thought to be educational.  (No offence meant to the author, its just
my critique of the tutorial.)

> For my first step i'm looking for a readable tutorial to the
> "gas"-assembler.

Simply start from http://www.linuxassembly.org 

Cheers,
anna

-- 

(15) I will never employ any device with a digital countdown. If I find
     that  such  a  device  is absolutely unavoidable, I will set it to
     activate when the counter reaches 117 and the hero is just putting
     his plan into operation. - Peter Anspach in "The Top 100 Things 
     I'd Do If I Ever Became An Evil Overlord"

                                            http://www.eviloverlord.com

Re: ld error

[Brian Raiter]

> I don't think so, because the given assembly program has a main
> function; and the tutorial has given a step by step procedure to
> produce the executable.  
> 
> Inspite of my above statement, I am not very sure of the given
> assembly program being complete, basically because it doesn't work!
> But it does have a main function.

Instead of having to build the link line yourself, you could just let
gcc do it for you. That is, instead of:

    ld -m elf_i386 -static average.o /usr/lib/crtn.o /foo/bar/baz blahblahblah

use:

    gcc -static average.o

b

Re: ld error

[J.S.Souza]

No, "main" doesn't have any special significance in assembly and is NOT 
required.  However, the assembler _does_ look for a procedure named "_start", 
but this also is not required because it will default to something else and 
just give you a warning about it if it's not included.  BTW, I understand how 
you feel about pulling your hair out, but this is the best way to learn _any_ 
language.  Also, all you really need to do to assemble and link a program is 
the following:
as -o hello.o hello
ld -o hello hello.o
All the other stuff is just extra.  I usually assembly my programs with 
--gstabs so that I can debug them with gdb, but it's not necessary for the 
program to assemble.  --gstabs is the same as the -g when compiling C 
programs.

			Cheers,
			Jeff Souza

On Monday 27 May 2002 10:27 pm, G Anna wrote:
> > Date: Mon, 27 May 2002 20:27:52 +0200
> > From: Alfred.Cleve@t-online.de (Alfred Cleve)
> > Subj: Re: ld error
> >
> > Hi,
> >
> > > I am working through 'Linux Assembly "Hello World" Tutorial, CS 200'
> > > by Bjorn Chambless.  But I am unable to compile the program given in
> > > that.  Kindly help me.
> >
> > i suspect that exercise isn't a simple "hello world"-program. It
> > seems to me as a nasty trap for lazy students :-))
> >
> > The module "average" is a subroutine e.g. a "function" which should
> > be linked to a given C-Program.
>
> I don't think so, because the given assembly program has a main
> function; and the tutorial has given a step by step procedure to
> produce the executable.
>
> Inspite of my above statement, I am not very sure of the given
> assembly program being complete, basically because it doesn't work!
> But it does have a main function.
>
> [ Added as an after-thought: Doesn't the function named 'main' have
> any special significance in assembly language programs? ]
>
> (begin-quote)
>
> /* segment registers set up by linked code */
> /* beginning of text(code) segment */
> .text
>         .align 4        /* set 4 double-word alignment */
> .globl main             /* make main global for linker */
>         .type main,@function    /* declare main as a function */
> main:
>      (definition of main snipped)
>
> (end-quote)
>
> If what you say is correct, then I don't think the tutorial serves its
> purpose.  Already, I am pulling my hairs to understand what is going
> on, and now I have got to put up with the caveats that the author
> thought to be educational.  (No offence meant to the author, its just
> my critique of the tutorial.)
>
> > For my first step i'm looking for a readable tutorial to the
> > "gas"-assembler.
>
> Simply start from http://www.linuxassembly.org
>
> Cheers,
> anna

Re: ld error

[Robert Plantz]

On Tuesday, May 28, 2002, at 04:26  AM, Brian Raiter wrote:

>> I don't think so, because the given assembly program has a main
>> function; and the tutorial has given a step by step procedure to
>> produce the executable.
>>
>> Inspite of my above statement, I am not very sure of the given
>> assembly program being complete, basically because it doesn't work!
>> But it does have a main function.
>
> Instead of having to build the link line yourself, you could just let
> gcc do it for you. That is, instead of:
>
>     ld -m elf_i386 -static average.o /usr/lib/crtn.o /foo/bar/baz 
> blahblahblah
>
> use:
>
>     gcc -static average.o

I use gas for teaching assembly language. I have my students simply
use
       gcc average.o -o average

Then they can use C library functions to do I/O. For example, I
have them use read() and write() to interact with the terminal. By
restricting them to read/write one byte at a time, I can give
several interesting assignments to help them learn how fundamental
C programming constructs are implemented at the assembly language
level. (Well, how they *could* be implemented; compilers
sometimes do silly things.)


>
> b
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-------------------------------------------------------
Robert G. Plantz, PhD			|
Professor of Computer Science	| cs.sonoma.edu/~bob
Sonoma State University			| plantz@sonoma.edu
1801 E. Cotati Ave.				| ph: 707.664.2806
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