Re: [PATCH v2] kasan: don't emit builtin calls when sanitization is off

From: Andrey Konovalov
Date: Mon Jan 22 2018 - 12:22:49 EST


On Fri, Jan 19, 2018 at 8:06 PM, Nick Desaulniers
<ndesaulniers@xxxxxxxxxx> wrote:
> Hmm... I had mentioned this patch to some coworkers who have much more
> knowledge about LLVM than me. They had concern that LLVM needs memset
> to be defined, and that there were discussions on the llvm mailing
> list about this.
>
> I'm digging through trying to find anything relevant, maybe this one
> about memcpy: https://lists.llvm.org/pipermail/llvm-dev/2012-May/050108.html
>
> I wonder if -ffreestanding is more appropriate?

I don't mind using either of those, they both fix the issue.

I'm struggling to understand the difference though. GCC documentation
doesn't really explain it [1] and Clang documentation [2] is
completely useless in this case.

[1] https://gcc.gnu.org/onlinedocs/gcc/Standards.html
[2] https://clang.llvm.org/docs/CommandGuide/clang.html