portconfigure.tcl - why does appending to an ENV variable (like CFLAGS) not also append to configure.cflags ?

[Ken Cunningham]

I noticed this recently "fixing" some ports that don't use a configure step.

During the run of portconfigure.tcl, various things (sdkroot) might be tested, and the appropriate values appended to the ENV variables.

But these things don't seem to come out in the configure.variables, like I would have expected them to.

Is this desired behaviour? 

Or should portconfigure flesh out the configure.variables at the same time as it's appending to the ENV variables (like I would have expected)?

(Please tell me I'm missing some well-known step that everyone else knows about but I don't :> )

Ken