I can't find any header files named atomic.h on the Linux machine:

hilbert.isi.edu 175% find /opt/oracle/solarisstudio12.3/include -name atomic.h
hilbert.isi.edu 176% find /usr/include -name atomic.h

On Solaris 10 (SPARC or x86):


cantor 684% find /usr/include -name atomic.h
/usr/include/atomic.h
/usr/include/sys/atomic.h

Perhaps there is a missing package that we need to install on RHEL.
I will ask about that today.