On an 8-CURRENT amd64 machine I get the stack trace: #0 0x00000008007053df in atexit () from /lib/libc.so.7 #1 0x0000000800706c8e in timeoff () from /lib/libc.so.7 #2 0x0000000800707355 in gmtime () from /lib/libc.so.7 #3 0x0000000000400638 in test (t=-33884019326476801) at test.c:7 #4 0x0000000000400686 in main () at test.c:15 -- Bruce Cran