Subject: Re: bug#18438: 24.4.50; assertion failed in bidi.c

From: Eli Zaretskii <[email-masked]>
Date: Fri, 10 Oct 2014 18:12:48 +0300

> Date: Fri, 10 Oct 2014 09:54:18 -0400
> From: Ken Brown <[email-masked]>
> CC: [email-masked]
> 
> It works:

Thanks.  Although I have a question to x86_64 experts here:

>     0x00000001004fc42b <+8>:     mov    %ecx,0x10(%rbp)
>     0x00000001004fc42e <+11>:    mov    0x10(%rbp),%eax
>     0x00000001004fc431 <+14>:    mov    %rax,-0x8(%rbp)

Do these 3 instructions ensure that the MSB 32 bits of RAX (and
therefore the place where the result is stored at RBP+0x08) are zeroed
out?

> Do you have a new theory that this is testing?

Something vague about the upper 32 bits of the 64-bit registers.
(Yes, I'm desperate.)