The base system started to provide certain pkgconfig files for
components it provides. This new variable allows ports to prefer base
copmonents explicitely using for example
PKGCONFIG_BASE=foo
This will create a symlingk of /usr/libdata/pkgconfig/foo.pc to
${WKRDIR}/.pkgconfig and adding said path to pkgconfigs search path.
This allows us to switch easily between base and port implementation
of different components (say openssl) by simply defining the appropriate
variable in (say ssl.mk).
Add context to the diff. Even without the context, I am sure that you put the symbols into the wrong namespace.