Created attachment 167313 [details]
synth build log
It appears that nghttp2 is incompatible with the version of OpenSSL currently in ports and is instead linking with the version in base by default. It's looking for functions starting with 'SSLv3_', which are not available in more recent versions of OpenSSL such as those in ports, but which are available in the version in base.
Attached is the build log from synth with WITH_OPENSSL_PORT=yes.
I'm hoping, if I have the time, to take a proper look at the issue some time this week and come up with a patch if I can.
This is not a www/nghttp2 issue but a devel/boost-libs issue.
To solve, use patch from https://github.com/pcbsd/freebsd-ports/blob/master/devel/boost-libs/files
A commit references this bug:
Date: Mon Mar 14 07:37:49 UTC 2016
New revision: 411050
Import upstream commit bae401b1eb0594932c4e780d496cba852c23b75f to
unbreak users of boost/asio/ssl when openssl is built without