On Sun Jan 28 01:51:11 2018, ckb wrote:
> at some point after commit 61c843815e7d23110e089b45ab4be270bc2a415d
> (tag: v9_12_0rc1)
> and before commit4c8cd59241040e161e6db3e58216e66e1f69c874 (HEAD ->
> v9_12, origin/v9_12, gitlab/v9_12)
> 
> When you run ./configure --without-openssl && make, the make fails:
> In file included from hmac_link.c:44:
> ./dst_openssl.h:18:10: fatal error: 'openssl/err.h' file not found
> #include <openssl/err.h>
> 
> (This was tested on OSX, but I see no evidence that it wouldnt happen
> with all platforms)

=> I can't see a reason to include this file even conditionally...
I vote to simply remove the include.