Created attachment 197977 [details]
Base GCC doesn't support -Wno-c++11-narrowing and the port builds without it.
Remove this to keep port bort building. Define USE_CXXSTD=c++98 to keep clang happy.
While here, add USES=gl.
Tested on powerpc64 and amd64.
Hardware sponsored by IntegriCloud.
A commit references this bug:
Date: Sun Oct 28 19:41:53 UTC 2018
New revision: 483330
Fix build with GCC-based architectures.
Submitted by: Piotr Kubaj
Approved by: portmgr (tier-2 blanket)