Comment # 28 on bug 1210313 from Benjamin Zeller

(In reply to Jan Engelhardt from comment #25)
> A mixed install is not supposed to be a problem (other than the fact that
> one has a mixed install to begin with):

One thing I noticed is that libressl has a lower openSSL API level than 
OpenSSL. So if we allow mixed install of e.g. libressl-devel + libopenssl3 
we have to be sure that compiling against libressl headers and linking to
openssl3 is not an issue.. 

Also in the end my binary had 2 libcrypto linked, yes I got a build time
warning but if tests hadn't failed I'd probably not have noticed it. 

Judging from the warning it seems that zchunk pulled in the other one:
> /usr/lib64/gcc/x86_64-suse-linux/13/../../../../x86_64-suse-linux/bin/ld: warning: libcrypto.so.3, needed by /usr/lib64/libzck.so, may conflict with libcrypto.so.50

(In reply to Jan Engelhardt from comment #26)
> > 39620905237184:error:0EFFF065:configuration file routines:CRYPTO_internal:missing equal sign:conf/conf_def.c:346:line 57
> 
> This error is not because of library mixing, but because SUSE's openssl-3
> has been patched with openssl-crypto-policies-support.patch to support *and
> distribute* a non-standard config file format that neither an unmodified
> openssl nor an unmodified libressl are able to understand.

I see, thats why google also did not bring anything helpful up...