Question about /usr/bin/gen_bridge_metadata

[Fredrik Öhrström]

When building build-infra/jdk8 build for mac, it hangs on:

/usr/bin/gen_bridge_metadata -d -F complete --framework
Foundation.framework -o Foundation.bridgesupport

which seems to take forever. At least, I have never seen it finish.
Also it also seems to exercise bash which runs a single thread full
speed, but not ruby.

I have a powerful 27" Corei7 8GBRAM, so clearly I should not have to
wait this long.
The -d option does not give much more info.

How can I debug this problem? Almost all of my other problems arrived
when I upgraded to OSX lion and
Xcode 4.3, could this be caused by the upgrade as well?

Thanks!

//Fredrik