I'm trying to get some binaries running on NixOS, and I ran into a weird situation when trying to get ldd
to find libpython2.7.so.1.0
and other libs.
$ ldd lldb
./lldb: /nix/store/5rjfisjzz6vgwmgf7zx25yd9p6rfs0zy-ncurses-6.2-abi5-compat/lib/libtinfo.so.5: no version information available (required by ./lldb)
./lldb: /nix/store/5rjfisjzz6vgwmgf7zx25yd9p6rfs0zy-ncurses-6.2-abi5-compat/lib/libtinfo.so.5: no version information available (required by /nix/store/nn8pr7xzam0rz7fq95x9dpi087xazsnv-theos/share/theos/toolchain/linux/iphone/usr/bin/./../lib/liblldb.so.10git)
linux-vdso.so.1 (0x00007ffd57b80000)
libpthread.so.0 => /nix/store/z56jcx3j1gfyk4sv7g8iaan0ssbdkhz1-glibc-2.33-56/lib/libpthread.so.0 (0x00007f921e821000)
liblldb.so.10git => /nix/store/nn8pr7xzam0rz7fq95x9dpi087xazsnv-theos/share/theos/toolchain/linux/iphone/usr/bin/./../lib/liblldb.so.10git (0x00007f9215c3c000)
libz.so.1 => /nix/store/1l4r0r4ab3v3a3ppir4jwiah3icalk9d-zlib-1.2.11/lib/libz.so.1 (0x00007f9215c1f000)
librt.so.1 => /nix/store/z56jcx3j1gfyk4sv7g8iaan0ssbdkhz1-glibc-2.33-56/lib/librt.so.1 (0x00007f9215c12000)
libdl.so.2 => /nix/store/z56jcx3j1gfyk4sv7g8iaan0ssbdkhz1-glibc-2.33-56/lib/libdl.so.2 (0x00007f9215c0d000)
libtinfo.so.5 => /nix/store/5rjfisjzz6vgwmgf7zx25yd9p6rfs0zy-ncurses-6.2-abi5-compat/lib/libtinfo.so.5 (0x00007f9215ba7000)
libm.so.6 => /nix/store/z56jcx3j1gfyk4sv7g8iaan0ssbdkhz1-glibc-2.33-56/lib/libm.so.6 (0x00007f9215a66000)
libstdc++.so.6 => /nix/store/c9f15p1kwm0mw5p13wsnvd1ixrhbhb12-gcc-10.3.0-lib/lib/libstdc++.so.6 (0x00007f9215891000)
libgcc_s.so.1 => /nix/store/c9f15p1kwm0mw5p13wsnvd1ixrhbhb12-gcc-10.3.0-lib/lib/libgcc_s.so.1 (0x00007f9215875000)
libc.so.6 => /nix/store/z56jcx3j1gfyk4sv7g8iaan0ssbdkhz1-glibc-2.33-56/lib/libc.so.6 (0x00007f92156b0000)
/nix/store/z56jcx3j1gfyk4sv7g8iaan0ssbdkhz1-glibc-2.33-56/lib/ld-linux-x86-64.so.2 => /nix/store/z56jcx3j1gfyk4sv7g8iaan0ssbdkhz1-glibc-2.33-56/lib64/ld-linux-x86-64.so.2 (0x00007f921e843000)
libpython2.7.so.1.0 => not found
libncurses.so.5 => not found
libform.so.5 => not found
libpanel.so.5 => not found
libuuid.so.1 => not found
libedit.so.2 => not found
libxml2.so.2 => not found
There are quite a few missing, but let's focus on libpython2.7.so.1.0
. When we check the RUNPATH
of ld64
,
$ readelf -d ld64 | rg RUNPATH
0x000000000000001d (RUNPATH) Library runpath: [/nix/store/c9f15p1kwm0mw5p13wsnvd1ixrhbhb12-gcc-10.3.0-lib/lib:/nix/store/z56jcx3j1gfyk4sv7g8iaan0ssbdkhz1-glibc-2.33-56/lib:/nix/store/xvyzi7cr0icnyavi5pm9rywjc4d8l7sx-libedit-20210714-3.1/lib:/nix/store/yxflij8cg4fgnzqmda91jx4d94jvkjf5-util-linux-2.37.2-lib/lib:/nix/store/370lxynzkmwrk8685jx9p2vgh7h0xp2h-libxml2-2.9.12/lib:/nix/store/5rjfisjzz6vgwmgf7zx25yd9p6rfs0zy-ncurses-6.2-abi5-compat/lib:/nix/store/nvx0l614cv661i5zz6w3j3y2w1xzppv1-python-2.7.18/lib:/nix/store/7344a20iqaja6i2qdz2xrgzy28rgnz5p-util-linux-2.37.2-lib/lib:/nix/store/1l4r0r4ab3v3a3ppir4jwiah3icalk9d-zlib-1.2.11/lib:$ORIGIN/../lib]
it contains /nix/store/nvx0l614cv661i5zz6w3j3y2w1xzppv1-python-2.7.18/lib
, which has our desired lib,
$ file /nix/store/nvx0l614cv661i5zz6w3j3y2w1xzppv1-python-2.7.18/lib/libpython2.7.so.1.0
/nix/store/nvx0l614cv661i5zz6w3j3y2w1xzppv1-python-2.7.18/lib/libpython2.7.so.1.0: ELF 64-bit LSB shared object, x86-64, version 1 (SYSV), dynamically linked, not stripped
I'm not sure how this is possible. The executable is also 64-bit, as we can see here:
$ file lldb
lldb: ELF 64-bit LSB executable, x86-64, version 1 (SYSV), dynamically linked, interpreter /nix/store/z56jcx3j1gfyk4sv7g8iaan0ssbdkhz1-glibc-2.33-56/lib/ld-linux-x86-64.so.2, for GNU/Linux 3.2.0, not stripped