Broke yum on Centos 6.10, cannot install missing GLIBC in error due to missing libunwind

Question

I was installing nvidia-drivers on Centos 6.10 which included a --skip-broken flag and may have broken yum. Whenever I ran yum commands this error pops up.

There was a problem importing one of the Python modules
required to run yum. The error leading to this problem was:

   /lib64/libc.so.6: version `GLIBC_2.14' not found (required by /lib64/libgcc_s.so.1)

Please install a package which provides this module, or
verify that the module is installed correctly.

It's possible that the above module doesn't match the
current version of Python, which is:
2.6.6 (r266:84292, Jun 20 2019, 14:14:55)
[GCC 4.4.7 20120313 (Red Hat 4.4.7-23)]

If you cannot solve this problem yourself, please go to
the yum faq at:
  http://yum.baseurl.org/wiki/Faq

I stumbled upon this thread which talks about installing the missing GLIBC version, but I ran into this error in step 8 ../configure --prefix=/opt/glibc-2.14

checking for forced unwind support... no
configure: error: forced unwind support is required

Which then took me to this forum thread that states I should install libunwind via yum. Which was my original problem, thus leaving me at an impasse. What should I do?

Answer 1

You need to reinstall GCC, or more precisely the libgcc package. Something overwrote /lib64/libgcc_s.so.1 with an incompatible version. You should be able to download the libgcc RPM package from a mirror, and then run:

# rpm --reinstall libgcc-4.4.7-23.el6.x86_64.rpm

This should still work because RPM itself does not depend on libgcc_s .

In general, if you need newer versions of these core system libraries (glibc, libstdc++, libgcc_s), you need to upgrade the entire operating system. Even if you manage to replace them in a consistent fashion, you are running something that isn't very close to the original operating system anymore. At that point, it is more prudent to upgrade, because that will give you a consistent system that has been tested by many others.