Isn't the C++ standard library backward-compatible?

Question

Hi. I'm working on a 64-bit Linux system, trying to build some code that depends on third-party libraries for which I have binaries. During linking, I get a stream of undefined reference errors for one of the libraries, indicating that the linker couldn't resolve references to standard C++ functions/classes, e.g.:

librxio.a(EphReader.o): In function `gpstk::EphReader::read_fic_data(std::basic_string<char, std::char_traits<char>, std::allocator<char> > const&)':
EphReader.cpp:(.text+0x27c): undefined reference to `std::basic_ostream<char, std::char_traits<char> >& std::__ostream_insert<char, std::char_traits<char> >(std::basic_ostream<char, std::char_traits<char> >&, char const*, long)'
EphReader.cpp:(.text+0x4e8): undefined reference to `std::basic_ostream<char, std::char_traits<char> >& std::__ostream_insert<char, std::char_traits<char> >(std::basic_ostream<char, std::char_traits<char> >&, char const*, long)'

I'm not really a C++ programmer, but this looks to me like it can't find the standard library. Doing some more research, I got the following when I looked at librxio's dependency for the standard library:

$ ldd librxio.so.16.0
./librxio.so.16.0: /usr/lib64/libstdc++.so.6: version `GLIBCXX_3.4.9' not found (required by ./librxio.so.16.0)
   libm.so.6 => /lib64/libm.so.6 (0x00002aaaaad45000)
   libstdc++.so.6 => /usr/lib64/libstdc++.so.6 (0x00002aaaaafc8000)
   libgcc_s.so.1 => /lib64/libgcc_s.so.1 (0x00002aaaab2c8000)
   libc.so.6 => /lib64/libc.so.6 (0x00002aaaab4d7000)
   /lib64/ld-linux-x86-64.so.2 (0x0000555555554000)

So I read that as saying that librxio (one of the third-party libraries) requires at least v3.4.9 of the standard library. But the version I have installed is 4.1.2:

$ rpm -qa | grep libstdc
compat-libstdc++-33-3.2.3-61.x86_64
libstdc++-devel-4.1.2-14.el5.i386
libstdc++-devel-4.1.2-14.el5.x86_64
libstdc++-4.1.2-14.el5.x86_64
libstdc++-4.1.2-14.el5.i386

Shouldn't this work? The shared object major number is 6, same as for v3.4.9. At this level, shouldn't this be backward compatible? It seems like the third-party library is looking for an earlier version of the standard library than what I have installed; but isn't there backward compatibility between versions with the same major number for the shared library? Again, I'm not really a C++ programmer; but I don't see what the problem is.

Any advice greatly appreciated. Thanks.

Answer 1

C++ runtimes tend to be compiler specific and the library that you're looking for definitely is compiler version specific. Keep in mind that even if the interface doesn't change, the internals might.

You'll either need to acquire libraries built with the same compiler & library versions that you have, or install the appropriate compiler/library versions.

Answer 2

Where did you get librxio.so.16.0? I think it's compiled with GCC > 4.1, and so it may not work with 4.1 runtime.