From: "Mark E." <snowball3 AT bigfoot DOT com>
To: djgpp-workers AT delorie DOT com, eliz AT is DOT elta DOT co DOT il
Date: Thu, 20 Jul 2000 09:27:15 -0400
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Subject: Re: GCC headers and DJGPP port
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In-reply-to: <200007201112.NAA14791@loewis.home.cs.tu-berlin.de>
References: <200007200642 DOT CAA09333 AT indy DOT delorie DOT com> (message from Eli	Zaretskii on Thu, 20 Jul 2000 02:42:48 -0400 (EDT))
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> Yes. Please re-read my message elaborating on __null semantics. Usage
> of __null does not result in an assembler-level reference to a symbol
> named __null; there is no such symbol. As a result, libc.a does not
> need to provide anything.
> 
> Instead, cc1plus will emit 'zero' immediate values in assembler,
> depending on the assembler language (e.g. clearing eax).
> 

Eli, this appears to be correct:

#include <stdio.h>

int main()
{
  char *null1 = __null;
  char *null2 = NULL;

  return 0;
}

	.file	"null.cpp"
gcc2_compiled.:
___gnu_compiled_cplusplus:
	.section .text
	.p2align 2
.globl _main
_main:
	pushl %ebp
	movl %esp,%ebp
	subl $24,%esp
	movl $0,-4(%ebp)
	movl $0,-8(%ebp)
	xorl %eax,%eax
	jmp L2
	xorl %eax,%eax
	jmp L2
	.p2align 4,,7
L2:
	movl %ebp,%esp
	popl %ebp
	ret