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Date:   Mon, 17 Aug 2020 12:15:20 -0700
From:   Kees Cook <keescook@chromium.org>
To:     Nick Desaulniers <ndesaulniers@google.com>
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        Arvind Sankar <nivedita@alum.mit.edu>,
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        Vishal Verma <vishal.l.verma@intel.com>,
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Subject: Re: [PATCH v2] lib/string.c: implement stpcpy
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On Mon, Aug 17, 2020 at 11:36:49AM -0700, Nick Desaulniers wrote:
> That said, this libcall optimization/transformation (sprintf->stpcpy)
> does look useful to me.  Kees, do you have thoughts on me providing
> the implementation without exposing it in a header vs using
> -fno-builtin-stpcpy?  (I would need to add the missing EXPORT_SYMBOL,
> as pointed out by 0day bot and on the github thread).  I don't care
> either way; I'd just like your input before sending a V+1.  Maybe
> better to just not implement it and never implement it?

I think I would ultimately prefer -fno-builtin-stpcpy, but for now,
sure, an implementation without a header (and a biiig comment above it
detailing why and a reference to the bug) would be fine by me.

-- 
Kees Cook