cwrappers and gcc -pipe

[David Brownlee <abs%absd.org@localhost>]

I've been trying to run some builds using cwrappers and everything
mostly works very well (and takes less time to do it :), but some
packages (such as sysutils/rename) fail configure with

gcc: Unknown transform rule: -pipe

I have "CFLAGS+=-pipe" in effectively mk.conf.

Should cwrappers be handling this?