compiling as root?

[Michael Thon]

Linux people generally recommend that you do not compile source code  
with a user that has superuser privileges, which I assume is a guard  
against possibly malicious commands that may be in the compile  
scripts.  When I install packages with macports (sudo port install  
xyz)  they're compiled by the root user.  I assume that the developers  
have thought about this and decided that it is not a security  
problem.  But I am curious, is it ok or not ok to compile source code  
as root?
cheers