C++ Logo


Advanced search

Re: [SG15] [isocpp-ext] Modularization of the standard library andABI stability

From: Tjernstrom, Staffan <Staffan.Tjernstrom_at_[hidden]>
Date: Mon, 9 Mar 2020 12:33:13 +0000
Somewhat backward looking, but a flavour of real-world user experience.

When implementing new libraries on the Microsoft toolchain, we've noticed that the current implementation of the STL module(s) as provided do not match our general compilation environment. In particular, the floating point mode mode differs between the two. That's probably an indication of the sort of issues that make this tricky.

But it does mean that for at least sorting purposes in that toolchain:

import std.vector;

does not equate to

#include <vector>

From: SG15 [mailto:sg15-bounces_at_[hidden]] On Behalf Of Bryce Adelstein Lelbach aka wash via SG15
Sent: Monday, 09 March, 2020 07:26
To: Evolution Working Group mailing list <ext_at_lists.isocpp.org>
Cc: Bryce Adelstein Lelbach aka wash <brycelelbach_at_[hidden]>; Ben Boeckel via Modules <modules_at_[hidden]>; C++ Library Evolution Working Group <lib-ext_at_[hidden]>; ISO C++ Tooling Study Group <sg15_at_[hidden]>; Nathan Sidwell <nathan_at_[hidden]>
Subject: Re: [SG15] [isocpp-ext] Modularization of the standard library andABI stability

If I understand correctly, you are suggesting that the reorganized modularized standard library could be ABI incompatible with the standard library you get with #includes.

I have noticed an interesting property of all the "compromise" proposals for ABI evolution; they are all the moral equivalent of std2. I'm not making any judgements on whether that is good or bad.

While I think your idea has merit, I think we should probably make it a design goal that:

import std.vector


#include <vector>

give you the same std::vector.

Does anyone disagree with that goal?


IMPORTANT: The information contained in this email and/or its attachments is confidential. If you are not the intended recipient, please notify the sender immediately by reply and immediately delete this message and all its attachments. Any review, use, reproduction, disclosure or dissemination of this message or any attachment by an unintended recipient is strictly prohibited. Neither this message nor any attachment is intended as or should be construed as an offer, solicitation or recommendation to buy or sell any security or other financial instrument. Neither the sender, his or her employer nor any of their respective affiliates makes any warranties as to the completeness or accuracy of any of the information contained herein or that this message or any of its attachments is free of viruses.

Received on 2020-03-09 07:36:00