Message-ID: <329B8876.2AA3@pobox.oleane.com>
Date: Wed, 27 Nov 1996 01:16:54 +0100
From: Francois Charton <deef AT pobox DOT oleane DOT com>
Organization: CCMSA
MIME-Version: 1.0
To: djgpp AT delorie DOT com
Subject: a.out format and objcopy
Content-Type: text/plain; charset=us-ascii
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As promised yesterday, here are the results of a few experiments with 
objcopy, and a.out format.

I tested all of this on a *very* simple "Hello world" program, namely

#include <stdio.h>

int main(void)
{
printf("Hello world\n");
return 0;
}

I compiled it using 

gcc -o hello.o -c hello.c

at this stage I get a COFF format hello.o object
when I link it (gcc -o hello.exe hello.o) everything runs allright

Then I tried using objcopy, to change my hello.o COFF object into an 
a.out object (which, the manual says, DJGPP ld also understands).
The command line was 

objcopy -O a.out-i386 hello.o hello2.o

I then tried to link 
gcc -o hello2.exe hello2.o

so far so good, except that the resulting program crashed on a SIGSEV 
fault.

Then, I tried to translate hello2.o back to coff format, saying
objcopy -O coff-go32 hello2.o hello3.o

-> obj copy complained at this point about aoutx.h (a file in the BFD 
source)
and then I tried to rebuild hello3.exe, it worked, but the resulting 
program also crashed.

To me, this is a problem with the implementation of a.out in BFD... Or 
did I do something wrong using objcopy?

Francois