I tried only your binary, didn't compiled by myself.
output of
dpkg-query -l libstdc++6
Code:
ii libstdc++6:amd64 6.3.0-18 amd64 GNU Standard C++ Library v3
ii libstdc++6:i386 6.3.0-18 i386 GNU Standard C++ Library v3
output of
dpkg-query -l libc6
Code:
ii libc6:amd64 2.24-11+deb9u1 amd64 GNU C Library: Shared libraries
ii libc6:i386 2.24-11+deb9u1 i386 GNU C Library: Shared libraries
output of
ldd sandbot.so
Code:
ldd sandbot.so
linux-gate.so.1 (0xdc4d0000)
libdl.so.2 => /lib/i386-linux-gnu/libdl.so.2 (0xdc414000)
libgcc_s.so.1 => /lib/i386-linux-gnu/libgcc_s.so.1 (0xdc3f6000)
libc.so.6 => /lib/i386-linux-gnu/libc.so.6 (0xdc23c000)
/lib/ld-linux.so.2 (0xdc4d1000)