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Date: Mon, 30 Jan 2017 09:32:30 +0800
From: He X <xw897002528@...il.com>
To: musl@...ts.openwall.com
Subject: Re: Re: a bug in bindtextdomain() and strip '.UTF-8'

> To Szabolcs Nagy: that's not how abi works...
1. I know, what i meant, is that: these symbols seems only called by stdc++
themselves, i havnt seen any program invoke these symbols directly, they
use std::locale() or something else. At least in my system, schroot does
not need to recompile, neither chromium, they worked well just after i
patched the toolchain. It's worth to checking if these symbols is used by
other binaries out of stdc++, if just 1 or 2, or even no, it's not a big
deal to apply this patch.

But now i change my mind, as you said, this not a perfect solution, indeed
there's a risk of breaking binaries. If it is on the way of upstreaming the
patch, i wont do like this.

> To Rich: So would this work?...
2. let me try it. :)

2017-01-30 0:40 GMT+08:00 Szabolcs Nagy <nsz@...t70.net>:

> * He X <xw897002528@...il.com> [2017-01-29 22:48:34 +0800]:
> > 2. no other ways, musl will use generic config 100%, and then the
> > exception, the run time error is hardcoded there; but i doubt if this
> > really breaks binaries, the function is only called by libstdc++ itself.
> > you cant only update the config, but does not update libstdc++. libstdc++
> > exported the same abi for common binaries, wont break most dynamic-loaded
> > binary in my view.
>
> that's not how abi works.. you change the __c_locale typedef
> of the generic config from int* to locale_t, such change
> breaks abi and cannot be upstreamed to gcc. (it's unfortunate
> that the c++ locale handling default for non-gnu systems
> does not use posix locales correctly, but breaking abi
> for all non-gnu systems is not an acceptable fix.)
>
> with your change the abi of libstdc++ would look like
> the current gnu abi:
>
> $ grep __locale_struct libstdc++-v3/config/abi/post/
> x86_64-linux-gnu/baseline_symbols.txt |wc -l
> 72
>
> the abi on a musl based system is like
>
> $ nm -D /usr/lib/libstdc++.so.6 |grep __locale_struct |wc -l
> 0
>
> so with your patch if a compiled binary refers to any one
> of those 72 symbols then the dynamic linker will fail to
> load it on a musl based system.
>

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