Defined in 5 files as a prototype:
- contrib/gcc/crtstuff.c, line 242 (as a prototype)
- contrib/libstdc++/libsupc++/cxxabi.h, line 142 (as a prototype)
- contrib/netbsd-tests/lib/libc/stdlib/h_atexit.c, line 43 (as a prototype)
- contrib/netbsd-tests/lib/libpthread/h_atexit.c, line 48 (as a prototype)
- lib/libc/stdlib/atexit.h, line 36 (as a prototype)