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From: Eli Zaretskii <eliz@gnu.org>
Newsgroups: gmane.emacs.devel
Subject: Re: Undefined behavior in OS X unexec detected by ASan
Date: Fri, 08 Apr 2016 11:27:34 +0300
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To: Philipp Stephani <p.stephani2@gmail.com>, John Wiegley <johnw@gnu.org>
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> From: Philipp Stephani <p.stephani2@gmail.com>
> Date: Sat, 02 Apr 2016 17:26:17 +0000
> 
> unexmacosx.c reads process memory directly, which tends to work in practice but is technically undefined
> behavior. I've attached a small patch that uses vm_read instead. According to ASan with this patch there's no
> more UB when dumping.

Would someone who uses OS X please see if this patch is OK?  Are there
any version-related caveats here (e.g., could some older OS X version
have trouble with this change)?

If everything's fine with the patch, we still need to decide to which
branch this should go.  John?