http://www.linuxforums.org/forum/coffee-lounge/197219-firefox-bloatware.html
On Monday, I tried to upgrade Firefox from version 21 to version 22. It hung on the final ld stage and then crashed. According to the kernel log, it had grabbed all my core and had been killed.
I posted a query on the Crux mailing list and received an answer today. According to this, building Firefox takes 4-6 GB! I am disgusted!