Spawn has problem to exit.

[kinkingmax]

When Process creation testing running, it may stuck, especially running at parallel prcoess creation.
I use gdb to see the status.
#0 0x00007fa17f8a912b in __lll_lock_wait_private () from /usr/lib/libc.so.6 #1 0x00007fa17f8a948f in __unregister_atfork () from /usr/lib/libc.so.6 #2 0x00007fa17f7daa69 in __cxa_finalize () from /usr/lib/libc.so.6 #3 0x00005576d2d1e298 in ?? () #4 0x00007ffc93a15480 in ?? () #5 0x00007fa17f9a08de in _dl_fini () from /lib64/ld-linux-x86-64.so.2

Then, I moved exit() from report() to main(). Added a variable to jump out While(1). The process can be stopped normally.