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From: Rich Felker <dalias@libc.org>
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Subject: Re: [PATCH] replace 'hlt' by 'ud2' in i386/x32/x86_64 a_crash
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Date: Fri, 17 Apr 2015 01:55:00 -0400
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On Thu, Apr 16, 2015 at 08:58:59PM +0300, Alexander Monakov wrote:
> ---
> ud2 is also what GCC and Clang use to implement __builtin_trap()
> 
> ud2 causes SIGILL rather than SIGSEGV; SIGSEGV is more likely to have a custom
> signal handler installed

I've pondered instead using:

	push $-1
	mov $175,%eax
	xor %ebx,%ebx
	mov %esp,%ecx
	int $128
	hlt // or ud2?

This should be uncatchable but it's moderately larger. 

Rich