Diagnosing why a port doesn't have binaries

[Ryan Schmidt]

I'm trying to diagnose why we're not providing binaries of the php ports. I'm guessing it's a license conflict. For example php depends on readline, and readline is under the gpl while php is under the php license, and those are listed as incompatible licenses in port_binary_distributable.tcl.

I recall we've switched some other ports from depending on readline to depending on libedit for this reason. Is that a good place for me to start?

Is there a good way to get a complete list of all the license incompatibilities or other reasons why a binary is not being provided, or do I have to manually go through the dependency chain and look at every port's license?