Currently, we can't upgrade sysutils/polkit to 0.116 (release 0.115 works fine). Because this version is buggy with Clang. This problem was fixed recently (see URL).
Yeah, I've been adding the spidermonkey60 port as it was needed for the polkit upgrade, but did not yet get to actually use it, and notice the issue :)
Thanks for digging up that upstream fix, I'll fix it asap.