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Reading symbols from /usr/sbin/nginx...Reading symbols from /usr/lib/debug//usr/sbin/nginx.debug...done.
done.
[New LWP 11662]

warning: Could not load shared library symbols for linux-vdso.so.1.
Do you need "set solib-search-path" or "set sysroot"?
[Thread debugging using libthread_db enabled]
Using host libthread_db library "/libx32/libthread_db.so.1".
Core was generated by `nginx:'.
Program terminated with signal SIGSEGV, Segmentation fault.
#0  0xf5c1ecd8 in ?? () from /libx32/libc.so.6
(gdb) bt
#0  0xf5c1ecd8 in ?? () from /libx32/libc.so.6
#1  0xf76dd86e in memcpy (__len=<optimized out>, __src=<optimized out>, __dest=<optimized out>)
    at /usr/include/bits/string3.h:51
#2  ngx_vslprintf (buf=<optimized out>, last=<optimized out>, fmt=0xf7788296 "V] ", args=args@entry=0xffd1ad2c)
    at src/core/ngx_string.c:247
#3  0xf76ddc52 in ngx_slprintf (buf=<optimized out>, last=last@entry=0xffd1b620 "", fmt=fmt@entry=0xf7788293 " [%V] ")
    at src/core/ngx_string.c:139
#4  0xf76d91ff in ngx_log_error_core (level=level@entry=7, log=<optimized out>, err=0, 
    fmt=fmt@entry=0xf778d6a8 "client %V closed keepalive connection") at src/core/ngx_log.c:104
#5  0xf77140b8 in ngx_http_keepalive_handler (rev=<optimized out>) at src/http/ngx_http_request.c:3153
#6  0xf76fc703 in ngx_epoll_process_events (cycle=<optimized out>, timer=<optimized out>, flags=<optimized out>)
    at src/event/modules/ngx_epoll_module.c:691
#7  0xf76f3807 in ngx_process_events_and_timers (cycle=cycle@entry=0xf79d9148) at src/event/ngx_event.c:248
#8  0xf76fa787 in ngx_worker_process_cycle (cycle=cycle@entry=0xf79d9148, data=data@entry=0x0)
    at src/os/unix/ngx_process_cycle.c:818
#9  0xf76f8ed1 in ngx_spawn_process (cycle=cycle@entry=0xf79d9148, proc=proc@entry=0xf76fa6a0 <ngx_worker_process_cycle>, 
    data=data@entry=0x0, name=name@entry=0xf778adfe "worker process", respawn=respawn@entry=-3)
    at src/os/unix/ngx_process.c:198
#10 0xf76fa9c7 in ngx_start_worker_processes (cycle=cycle@entry=0xf79d9148, n=1, type=type@entry=-3)
    at src/os/unix/ngx_process_cycle.c:364
#11 0xf76fb53c in ngx_master_process_cycle (cycle=<optimized out>) at src/os/unix/ngx_process_cycle.c:136
#12 0xf76d7af9 in main (argc=<optimized out>, argv=<optimized out>) at src/core/nginx.c:407
(gdb) quit