尽管设置了 rpath，但没有找到一个 dll

Posted 2023-02-19

【中文标题】尽管设置了 rpath，但没有找到一个 dll

【英文标题】：Despite rpath is set, one dll is not found

【发布时间】：2018-03-23 08:41:45

【问题描述】：

ldd 找不到 rpath 定义中存在的 dll。找到其他一些库（检查 /./../lib/*）

这里是 ldd 的输出（我们可以看到 ../lib 中有 2 个 dll，但 libexpat.so.0 中没有：

root@hyperstream:/DT/local/ADE-trunk4/build-ADE-Desktop-Default/bin# ldd ./ade_admin linux-vdso.so.1 => (0x00007ffeb9796000) libadeversion.so => /DT/local/ADE-trunk4/build-ADE-Desktop-Default/bin/./../lib/libadeversion.so (0x00007f31abaef000) libuuid.so.1 => /lib/x86_64-linux-gnu/libuuid.so.1 (0x00007f31ab8ca000) libpthread.so.0 => /lib/x86_64-linux-gnu/libpthread.so.0 (0x00007f31ab6ac000) libaprutil-1.so.0 => /DT/local/ADE-trunk4/build-ADE-Desktop-Default/bin/./../lib/libaprutil-1.so.0 (0x00007f31ab58c000) libapr-1.so.0 => /DT/local/ADE-trunk4/build-ADE-Desktop-Default/bin/./../lib/libapr-1.so.0 (0x00007f31ab460000) libavahi-client.so.3 => /usr/lib/x86_64-linux-gnu/libavahi-client.so.3 (0x00007f31ab24d000) libavahi-common.so.3 => /usr/lib/x86_64-linux-gnu/libavahi-common.so.3 (0x00007f31ab041000) libdl.so.2 => /lib/x86_64-linux-gnu/libdl.so.2 (0x00007f31aae3d000) libstdc++.so.6 => /usr/lib/x86_64-linux-gnu/libstdc++.so.6 (0x00007f31aaab5000) libm.so.6 => /lib/x86_64-linux-gnu/libm.so.6 (0x00007f31aa7ac000) libgcc_s.so.1 => /lib/x86_64-linux-gnu/libgcc_s.so.1 (0x00007f31aa595000) libc.so.6 => /lib/x86_64-linux-gnu/libc.so.6 (0x00007f31aa1cc000) /lib64/ld-linux-x86-64.so.2 (0x0000560d30a76000) libexpat.so.0 => 未找到 librt.so.1 => /lib/x86_64-linux-gnu/librt.so.1 (0x00007f31a9fc4000) [...]

root@hyperstream:/DT/local/ADE-trunk4/build-ADE-Desktop-Default/bin# 文件 ../lib/libexpat.so.0 ../lib/libexpat.so.0：ELF 64 位 LSB 共享 对象，x86-64，版本 1 (SYSV)，动态链接， BuildID[sha1]=762de704943d03033d01a9725216d6b05d0740f5，未剥离

这里是rpath：

root@hyperstream:/DT/local/ADE-trunk4/build-ADE-Desktop-Default/bin# readelf -d ade_admin | grep 'R.*PATH' 16: 0x000000000000001d (RUNPATH) 库运行路径：[$ORIGIN/../lib]

现在是杀手锏：它适用于 clang 3.8，但适用于 gcc 6.3 (ubuntu 16.10)

显然添加一个 LD_LIBRARY_PATH=../lib 使它再次工作，但 rpath 的目标是避免设置它

root@hyperstream:/DT/local/ADE-trunk4/build-ADE-Desktop-Default/bin# 导出 LD_LIBRARY_PATH=../lib root@hyperstream:/DT/local/ADE-trunk4/build-ADE-Desktop-Default/bin# ldd ./ade_admin linux-vdso.so.1 => (0x00007ffea23b6000) libadeversion.so => ../lib/libadeversion.so (0x00007f78c6474000) libuuid.so.1 => /lib/x86_64-linux-gnu/libuuid.so.1 (0x00007f78c624f000) libpthread.so.0 => /lib/x86_64-linux-gnu/libpthread.so.0 (0x00007f78c6031000) libaprutil-1.so.0 => ../lib/libaprutil-1.so.0 (0x00007f78c5f11000) libapr-1.so.0 => ../lib/libapr-1.so.0 (0x00007f78c5de5000) libavahi-client.so.3 => /usr/lib/x86_64-linux-gnu/libavahi-client.so.3 (0x00007f78c5bd2000) libavahi-common.so.3 => /usr/lib/x86_64-linux-gnu/libavahi-common.so.3 (0x00007f78c59c6000) libdl.so.2 => /lib/x86_64-linux-gnu/libdl.so.2 (0x00007f78c57c2000) libstdc++.so.6 => /usr/lib/x86_64-linux-gnu/libstdc++.so.6 (0x00007f78c543a000) libm.so.6 => /lib/x86_64-linux-gnu/libm.so.6 (0x00007f78c5131000) libgcc_s.so.1 => /lib/x86_64-linux-gnu/libgcc_s.so.1 (0x00007f78c4f1a000) libc.so.6 => /lib/x86_64-linux-gnu/libc.so.6 (0x00007f78c4b51000) /lib64/ld-linux-x86-64.so.2 (0x0000559fdceab000) libexpat.so.0 => ../lib/libexpat.so.0 (0x00007f78c492a000)

有什么想法吗？

问候

劳伦特

【问题讨论】：

您知道，“DLL”是共享库的Windows 特定 名称。在 Linux/Unix 领域，我们只称它们为“共享库”或“SOs”（发音为“ess ohs”）。在同一个句子中看到“RPATH”和“DLL”很奇怪，因为 Windows 没有等效的 RPATH。

【参考方案1】：

我只是找到了解释：clang 放入了 elf 二进制 ALL 库的 [NEEDED] 部分（甚至我自己没有明确包含的库，但我包含的库的 [NEEDED] 部分引用了这些库

来自 gcc 的示例：

readelf -d my_prog

Dynamic section at offset 0x9cb548 contains 46 entries:
  Tag        Type                         Name/Value
 0x0000000000000001 (NEEDED)             Shared library: [libadeversion.so]
 0x0000000000000001 (NEEDED)             Shared library: [libuuid.so.1]
 0x0000000000000001 (NEEDED)             Shared library: [libsqlite3.so]
 0x0000000000000001 (NEEDED)             Shared library: [libpthread.so.0]
 0x0000000000000001 (NEEDED)             Shared library: [libaprutil-1.so.0]
 0x0000000000000001 (NEEDED)             Shared library: [libapr-1.so.0]
 0x0000000000000001 (NEEDED)             Shared library: [libavahi-client.so.3]
 0x0000000000000001 (NEEDED)             Shared library: [libavahi-common.so.3]
 0x0000000000000001 (NEEDED)             Shared library: [libdl.so.2]
 0x0000000000000001 (NEEDED)             Shared library: [libaio.so.1]
 0x0000000000000001 (NEEDED)             Shared library: [librt.so.1]
 0x0000000000000001 (NEEDED)             Shared library: [lib_adm64.so]
 0x0000000000000001 (NEEDED)             Shared library: [lib_dict64.so]
 0x0000000000000001 (NEEDED)             Shared library: [lib_rdm64.so]
 0x0000000000000001 (NEEDED)             Shared library: [lib_dbr64.so]
 0x0000000000000001 (NEEDED)             Shared library: [libstdc++.so.6]
 0x0000000000000001 (NEEDED)             Shared library: [libm.so.6]
 0x0000000000000001 (NEEDED)             Shared library: [libgcc_s.so.1]
 0x0000000000000001 (NEEDED)             Shared library: [libc.so.6]
 0x000000000000001d (RUNPATH)            Library runpath: [$ORIGIN/../lib/:$ORIGIN/../lib/:../lib/]

来自铿锵声：

readelf -d my_prog

Dynamic section at offset 0xa7bae8 contains 54 entries:
  Tag        Type                         Name/Value
 0x0000000000000001 (NEEDED)             Shared library: [libadeversion.so]
 0x0000000000000001 (NEEDED)             Shared library: [libuuid.so.1]
 0x0000000000000001 (NEEDED)             Shared library: [libsqlite3.so]
 0x0000000000000001 (NEEDED)             Shared library: [libpthread.so.0]
 0x0000000000000001 (NEEDED)             Shared library: [libaprutil-1.so.0]
 0x0000000000000001 (NEEDED)             Shared library: [libexpat.so.0]
 0x0000000000000001 (NEEDED)             Shared library: [libapr-1.so.0]
 0x0000000000000001 (NEEDED)             Shared library: [libavahi-client.so.3]
 0x0000000000000001 (NEEDED)             Shared library: [libavahi-common.so.3]
 0x0000000000000001 (NEEDED)             Shared library: [libdl.so.2]
 0x0000000000000001 (NEEDED)             Shared library: [libaio.so.1]
 0x0000000000000001 (NEEDED)             Shared library: [libcrypt.so.1]
 0x0000000000000001 (NEEDED)             Shared library: [librt.so.1]
 0x0000000000000001 (NEEDED)             Shared library: [lib_adm64.so]
 0x0000000000000001 (NEEDED)             Shared library: [lib_dict64.so]
 0x0000000000000001 (NEEDED)             Shared library: [lib_rdm64.so]
 0x0000000000000001 (NEEDED)             Shared library: [lib_rpc64.so]
 0x0000000000000001 (NEEDED)             Shared library: [lib_sql64.so]
 0x0000000000000001 (NEEDED)             Shared library: [lib_rdbc64.so]
 0x0000000000000001 (NEEDED)             Shared library: [lib_rm64.so]
 0x0000000000000001 (NEEDED)             Shared library: [lib_ncp64.so]
 0x0000000000000001 (NEEDED)             Shared library: [lib_cmp64.so]
 0x0000000000000001 (NEEDED)             Shared library: [lib_repfltr64.so]
 0x0000000000000001 (NEEDED)             Shared library: [lib_expat64.so]
 0x0000000000000001 (NEEDED)             Shared library: [lib_cncp64.so]
 0x0000000000000001 (NEEDED)             Shared library: [lib_dbr64.so]
 0x0000000000000001 (NEEDED)             Shared library: [libstdc++.so.6]
 0x0000000000000001 (NEEDED)             Shared library: [libm.so.6]
 0x0000000000000001 (NEEDED)             Shared library: [libgcc_s.so.1]
 0x0000000000000001 (NEEDED)             Shared library: [libc.so.6]
 0x000000000000001d (RUNPATH)            Library runpath: [$ORIGIN/../lib/:$ORIGIN/../lib/:../lib/]

还有一个 dll 包括缺少的一个 libexpat：

readelf -d ../lib/libaprutil-1.so.0 

Dynamic section at offset 0x1e698 contains 29 entries:
  Tag        Type                         Name/Value
 0x0000000000000001 (NEEDED)             Shared library: **[libexpat.so.0]**
 0x0000000000000001 (NEEDED)             Shared library: [libapr-1.so.0]
 0x0000000000000001 (NEEDED)             Shared library: [libuuid.so.1]
 0x0000000000000001 (NEEDED)             Shared library: [librt.so.1]
 0x0000000000000001 (NEEDED)             Shared library: [libcrypt.so.1]
 0x0000000000000001 (NEEDED)             Shared library: [libpthread.so.0]
 0x0000000000000001 (NEEDED)             Shared library: [libdl.so.2]
 0x0000000000000001 (NEEDED)             Shared library: [libc.so.6]
 0x000000000000000e (SONAME)             Library soname: [libaprutil-1.so.0]

但是 RUNPATH 只被二进制文件使用而不被 dll 使用（也可以有自己的 RUNPATH）。

2 解决方案： - 在 libaprutil-1.so.0 中添加一个 RUNPATH 以强制包含来自“.”的库 - 在我的构建中明确添加所有缺少的 dll

希望对你有帮助