https://bugzilla.redhat.com/bugzilla/show_bug.cgi?id=232371 diff -u -rup gdb-6.6-orig/gdb/linux-nat.c gdb-6.6/gdb/linux-nat.c --- gdb-6.6-orig/gdb/linux-nat.c 2007-03-15 19:55:40.000000000 -0400 +++ gdb-6.6/gdb/linux-nat.c 2007-03-15 20:02:09.000000000 -0400 @@ -1014,6 +1014,10 @@ lin_lwp_attach_lwp (ptid_t ptid, int ver { /* Try again with __WCLONE to check cloned processes. */ pid = my_waitpid (GET_LWP (ptid), &status, __WCLONE); + if (pid == -1 && errno == ECHILD) + error (_("Can't attach %s (%s) - possible SELinux denial," + " check your /var/log/messages for `avc: denied'"), + target_pid_to_str (ptid), safe_strerror (errno)); lp->cloned = 1; }