While upgrading an old gentoo box I encountered this error:

xgettext: error while loading shared libraries: libexpat.so.0: cannot open shared object file: No such file or directory

I tried fixing it with revdep-rebuild tool but it failed too. Through some research I found this is a common error consequence of a broken update process (nothing is perfect in this life) due to a circular dependency.

But you don't have to worry, there is a simple way to fix this:
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