Re: [gentoo-dev] [RFC] C++ standard in ebuilds

[Richard Yao <ryao@gentoo.org>]

> On Sep 17, 2018, at 12:40 PM, Vadim A. Misbakh-Soloviov <gentoo@mva.name> wrote:
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> I'd prefer to wait another replies on the list for the main theme of this e-
> mail, but this problem also affects C (so, as **c**flags and C standards), so 
> solution shoudn't be c++ specific, imho.
You would think that, but the C standard version does not effect ABI compatibility. We had a very long discussion about this in OpenZFS because the other platforms were using C99 while we had backported everything to C89 on Linux because of the Linux kernel. No one could find a single example of ABI breakage caused by mixing and matching C89 and C99 (C99 LKM and C89 kernel). After a few years of not a single example being raised, the Linux team lead opted to adopt C99.

Now, there are flags affecting the ABI, but those are separate from the C standard version. As for C++, mixing standard versions does go badly because new language features require ABI changes.
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