Internal compiler error
A few years ago I was doing lot of Linux kernel builds. My desktop computer, which is Athlon 64 X2 4600+ and 2x GeIL PC2-6400 DDR2-800 C4 ULTRA DUAL CHANNEL (2x1GB each; 4GB total), was doing make -j6 (or -j8, don't remember now) of kernel one after another. After many many hours some builds started to failing with mentioned error. Let's say 1 of 4. I had to do it, so I was repeating make (automatically) till it succeeded, but later I fiddled with memtest86+. It was running day and night on all 10 tests (I believe that was test count back then) and something popped up finally (I wasn't checking it constantly) [1]. But you know what? When I switched to showing badram patterns later and the problem reappeared, it was red line without any pattern! I used to see some addresses and such whenever error was detected by memtest (or experience computer halt, etc.), but that time I had seen nothing - it was quite enigmatic. I've checked memtest sources and test 5 was filtered out from showing badram patterns as apparently not being reliable. I changed it (I've just found the changed sources on the disk and diffed it to the original release [2]), recompiled the memtest and run it again. I got badram patterns this time [3].
I needed BadRAM patterns to secure myself from being constantly hit by this memory problem, but I don't remember whether I used them in the end.
I still use this computer. No big compiles, no big problems, but sometimes I get the iffy feeling. :) I had a few BSODs since then and I believe they were caused by this memory problem. Haven't seen its manifestation for a long long time. Maybe my computer was simply overheated back then? Since then I'm much more into checksums than I used to be...
[1] http://i.imgur.com/RMhCOLM.jpg
[2] https://gist.github.com/przemoc/5250861
[3] http://i.imgur.com/jFHZkVA.jpg