如何在 g++ 中链接同一库的不同版本? [英] How do I link different versions of the same library in g++?

问题描述

我试图弄清楚如何在 SLES10 机器上加载两个不同版本的 libstdc++.so.我的客户端有一个进程 Foo，它是用 GCC 4.1.2 构建的，因此使用 6.0.8 版本的 libstdc++.so.我们还在构建名为 libBar.so 的共享库.这个库将在运行时由 Foo 动态加载.libBar.so 使用 GCC 4.3.6 和 libstdc++ 版本 6.0.10 编译.

I'm trying to figure out how to load two different versions of libstdc++.so on a SLES10 machine. My client has a process Foo, which is built with GCC 4.1.2, and thus uses the 6.0.8 version of libstdc++.so. We are also building shared library called libBar.so. This library will be dynamically loaded by Foo at runtime. libBar.so is compiled using GCC 4.3.6, and libstdc++ version 6.0.10.

目前，当我尝试让 Foo 加载 libBar.so 时，出现以下错误.

Currently, when I try to have Foo load libBar.so, I get the following error.

错误:无法加载共享对象'/usr/lib64/libBar.so':/usr/lib64/libstdc++.so.6:未找到版本GLIBCXX_3.4.9"(/usr/lib64/libBar.so 需要)

error: unable to load shared object '/usr/lib64/libBar.so': /usr/lib64/libstdc++.so.6: version `GLIBCXX_3.4.9' not found (required by /usr/lib64/libBar.so)

目前，我可以让它工作的唯一方法是更改​​我的库加载顺序(通过 ld.so.conf)，以便 Foo 和 libbar.so 都加载相同的 (6.0.10) libstdc++.所以.但是，这不是一个可行的解决方案，因为它需要我修改客户端的系统.

At the moment, the only way that I can get this to work is to change my library load order (via ld.so.conf) so that Foo and libbar.so both load the same (6.0.10) libstdc++.so. However, this isn't a vialbe solution, since it requires that I modify the client's system.

我想做的是让 Foo 加载它的 libstdc++.so 版本和 libBar.so 链接到它自己的 libstdc++.so 版本，但我不知道如何编写我的 Makefile 来实现这一点.这是我目前所拥有的，对于 Makefile.am 中的 LIBADD 行...

What I'd like to do is have Foo load it's verions of libstdc++.so and libBar.so link to it's own version of libstdc++.so, but I can't figure out how to write my Makefile to make that happen. Here's what I have so far, for my LIBADD line in Makefile.am...

libBar_la_LIBADD = ../../vendor/SLES10/lib/libstdc++.so.6.0.10

libBar_la_LIBADD = ../../vendor/SLES10/lib/libstdc++.so.6.0.10

我假设想要那个特定版本的 libstdc++.so.但是，当我对完全编译和链接的 libBar.so 运行 ldd 时，这是我看到的行...

Which I would assume would like to that SPECIFIC version of libstdc++.so. However, when I run ldd against the fully compiled and linked libBar.so, this is the line I see...

libstdc++.so.6 =>/usr/lib64/libstdc++.so.6 (0x00002aaaaeac5000)

libstdc++.so.6 => /usr/lib64/libstdc++.so.6 (0x00002aaaaeac5000)

为什么它不专门链接到 libstdc++.so.6.0.10?我应该怎么做?

Why isn't it linking specifically to libstdc++.so.6.0.10? What should I be doing instead?

推荐答案

我在使用过时版本的 libstdc++ 的第 3 方库中遇到了类似问题.

I had a similar issue with a 3rd-party library that used an obsolete version of libstdc++.

我通过将第 3 方库与旧版本的 libstdc++ 进行静态预链接解决了这个问题.最终结果是另一个没有未解析的 libstdc++ 符号的共享库.命令行是这样的:

I solved it by pre-linking the 3rd-party library statically with that old version of libstdc++. The end result was another shared library that did not have unresolved libstdc++ symbols. The command line was something like this:

ld --relocatable -o lib3rd-party-prelinked.so lib3rd-party.so /usr/lib64/libstdc++.a.6

然后我使用 lib3rd-party-prelinked.so 而不是 lib3rd-party.so.(在 man ld 中查找 --relocatable).

And then I used lib3rd-party-prelinked.so instead of lib3rd-party.so. (Lookup --relocatable in man ld).

在我的情况下这是可能的，因为第 3 方库暴露了 C API，其接口中没有使用 C++ 标准库组件.

It was possible in my case because the 3rd-party library exposed a C API, no C++ standard library components were used in its interface.

如果您的第 3 方库在其接口中公开了 C++ 标准库类，其 ABI 在这些 libstdc++ 版本之间是不同的，那将无法正常工作.例如.您的应用程序将带有新 ABI 的 std::list<> 传递给第三方库，该库需要带有旧 ABI 版本的 std::list<>.即使它链接，也会在运行时导致未定义的行为.

If your 3rd-party library exposes C++ standard library classes in its interface whose ABIs are different between these libstdc++ versions, that is not going to work. E.g. your application passes a std::list<> with the new ABI to the 3rd-party library that expects a std::list<> with the old ABI version. Even if it links, that will cause undefined behaviour at run-time.

这篇关于如何在 g++ 中链接同一库的不同版本?的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！