The rpms are compiled both with and without debugging, the debugging versions
will run more slowly ... however they also have assert() calls to notify you
of any problems, either with the use of the API or (hopefully a lot less likely)
bugs in the library itself.

 Both versions are compiled with internal sprintf double support (and that is
the default if you compile from the source rpm).

 The redhat-8.0 directory contains rpms built on redhat-8.0, this uses
glibc-2.3 and gcc-3.2 ... and so should be compatible with ditributions that
also ship those.

 The redhat-7.3 directory contains rpms built on redhat-7.3, which uses
glibc-2.2 and gcc-2.96 ... and so should be compatible with ditributions that
also ship those.

 The src directory contains the source RPM, to build the binary rpms. The
source itself is contained in a versioned directory above this one ... and is
archived for much longer.