The GCC 4.1.2 documentation has this to say about the -pipe
option:
-pipe
Use pipes rather than temporary files for communica
Honestly there is very little reason to not use it. -pipe will only use a tad more ram, which if this box is building code, I'd assume has a decent amount. It can significantly improve build time if your system is using a more conservative filesystem that writes and then deletes all the temporary files along the way (ext3, for example.)