error: dereferencing pointer to incomplete type DH {aka struct dh_st}

[Salz, Rich]

>    I'm attempting to build our RHEL 7 based product on RHEL 8 and running into a lot of changes from openssl 1.0.2k-fips (RHEL 7) to 1.1.1 FIPS (RHEL 8).  I haven't found a good guide to adapting the sources to these changes.

Web search for "openssl opaque accessors" turns up many hits; these two seem useful:
  
	https://wiki.openssl.org/index.php/OpenSSL_1.1.0_Changes
	http://vega.pgw.jp/~kabe/vsd/migrate2openssl-1.1.html 
 
PS: A long confidential email disclaimer is silly, particularly when posting to a large public mailing list. :)