I have a lower power system with only 1GB of ram (and 8 GB of swap). Because the system is so slow, I have set MAKEOPTS="-j1" even though it has 4 cores. While compiling I noticed the system became horribly slow, and when I was able to finally open top I saw 6 instances of cc1plus. This ebuild ignores my MAKEOPTS option and is launching way to many processes, freezing my system and thrashing my swap device.
*** This bug has been marked as a duplicate of bug 652200 ***