From:	Eric Rudd <rudd AT cyberoptics DOT com>
Newsgroups:	comp.os.msdos.djgpp
Subject:	Re: Possible gcc bug
Date:	Tue, 09 Jun 1998 11:03:12 -0500
Organization:	CyberOptics
Lines:	37
Message-ID:	<357D5CC0.212234B0@cyberoptics.com>
References:	<357D578B DOT 1088A0F9 AT cyberoptics DOT com>
Reply-To:	rudd AT cyberoptics DOT com
NNTP-Posting-Host:	rudd.cyberoptics.com
Mime-Version:	1.0
To:	djgpp AT delorie DOT com
DJ-Gateway:	from newsgroup comp.os.msdos.djgpp

Eric Rudd wrote:
> 
> I have isolated what I think is a register-allocation bug in gcc

Sorry, the attachment got lost on my end; here it is:

	.file	"bad.c"
gcc2_compiled.:
___gnu_compiled_c:
.text
	.align 4
.globl _alias
_alias:
	pushl %ebp
	movl %esp,%ebp
	pushl %esi
	pushl %ebx
	movl 8(%ebp),%esi
	movl %esi,%eax
	movl 12(%ebp),%ebx
/APP
	
      xorl  %eax, %eax
      xorl  %edx, %edx
      xorl  %ecx, %ecx
   
/NO_APP
	movl 16(%ebp),%ebx   <= points to arg3
	movl 20(%ebp),%ebx   <= overwrites pointer (??)
	movl %edx,(%ebx)
	movl %eax,(%ebx)     <= writes to *arg4 instead of *arg3
	leal -8(%ebp),%esp
	popl %ebx
	popl %esi
	movl %ebp,%esp
	popl %ebp
	ret

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