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<p class="MsoNormal">Hi All,<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">After upgrading to Erlang R22, my software crashes the Erlang VM with Segmentation fault.<o:p></o:p></p>
<p class="MsoNormal">It happens rarely, only after several days of test workload, so I can’t really reproduce.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">I made more than 10 core dumps so far, loaded them into gdb, and all of them died at these 2 crash points:<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Program terminated with signal 11, Segmentation fault.<o:p></o:p></p>
<p class="MsoNormal">#0 process_main (x_reg_array=0x20002, f_reg_array=0x2ade29280590) at x86_64-unknown-linux-gnu/opt/smp/beam_hot.h:4064<o:p></o:p></p>
<p class="MsoNormal">4064 if (is_not_tuple(r(0))) {<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">or<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">#0 process_main (x_reg_array=0x20002, f_reg_array=0x2) at x86_64-unknown-linux-gnu/opt/smp/beam_hot.h:5252<o:p></o:p></p>
<p class="MsoNormal">5252 c_p->seq_trace_lastcnt = unsigned_val(SEQ_TRACE_TOKEN_SERIAL(c_p));<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">The software is not doing any tracing when the crash happens, nor does it have any NIFs.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">What should be the next step of investigation?<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Thanks<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal"><span style=font-size:10.0pt;font-family:"Arial","sans-serif";color:black>Andras G. Bekes <br />
</span><o:p></o:p></p>
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