MySQL upgrading from 5.7 to 8 - Throwing strange error and won't start up I followed the instructions on the MySQL web site and got MySQL server 8 mostly installed but it won't launch because it fails pretty quickly during the upgrade process. The apt-get portion installed all the files. But when it launches this is what is added to my error.log file and I have no clue what to make of it and Google is not being helpful.

2018-09-07T12:25:54.281373Z 0 [System] [MY-010116] [Server] /usr/sbin/mysqld (mysqld 8.0.12) starting as process 3662
mysqld: /export/home/pb2/build/sb_0-29394547-1530206990.8/release/mysql-8.0.12/sql/dd/upgrade/table.cc:1075: bool dd::upgrade_57::add_triggers_to_table(THD*, TABLE*, const String_type&amp;, const String_type&amp;): Assertion `t-&gt;get_event() &gt;= t_type &amp;&amp; (t-&gt;get_event() &gt; t_type || t-&gt;get_action_time() &gt;= t_time)' failed.
12:27:19 UTC - mysqld got signal 6 ;
This could be because you hit a bug. It is also possible that this binary
or one of the libraries it was linked against is corrupt, improperly built,
or misconfigured. This error can also be caused by malfunctioning hardware.
Attempting to collect some information that could help diagnose the problem.
As this is a crash and something is definitely wrong, the information
collection process might fail.

key_buffer_size=16777216
read_buffer_size=131072
max_used_connections=0
max_threads=300
thread_count=1
connection_count=0
It is possible that mysqld could use up to 
key_buffer_size + (read_buffer_size + sort_buffer_size)*max_threads = 134902 K  bytes of memory
Hope that's ok; if not, decrease some variables in the equation.

Thread pointer: 0x55ae33b103a0
Attempting backtrace. You can use the following information to find out
where mysqld died. If you see no messages after this, something went
terribly wrong...
stack_bottom = 7f082a824da0 thread_stack 0x30000
/usr/sbin/mysqld(my_print_stacktrace(unsigned char*, unsigned long)+0x3d) [0x55ae31bc258d]
/usr/sbin/mysqld(handle_fatal_signal+0x423) [0x55ae30dfcde3]
/lib/x86_64-linux-gnu/libpthread.so.0(+0x12890) [0x7f083e593890]
/lib/x86_64-linux-gnu/libc.so.6(gsignal+0xc7) [0x7f083c98fe97]
/lib/x86_64-linux-gnu/libc.so.6(abort+0x141) [0x7f083c991801]
/lib/x86_64-linux-gnu/libc.so.6(+0x3039a) [0x7f083c98139a]
/lib/x86_64-linux-gnu/libc.so.6(+0x30412) [0x7f083c981412]
/usr/sbin/mysqld(+0x1abc55b) [0x55ae31b8155b]
/usr/sbin/mysqld(dd::upgrade_57::migrate_all_frm_to_dd(THD*, char const*, bool)+0x562) [0x55ae31b82042]
/usr/sbin/mysqld(dd::upgrade_57::fill_dd_and_finalize(THD*)+0xf2) [0x55ae31b554f2]
/usr/sbin/mysqld(+0xde1e96) [0x55ae30ea6e96]
/usr/sbin/mysqld(+0x1f920af) [0x55ae320570af]
/lib/x86_64-linux-gnu/libpthread.so.0(+0x76db) [0x7f083e5886db]
/lib/x86_64-linux-gnu/libc.so.6(clone+0x3f) [0x7f083ca7288f]

Trying to get some variables.
Some pointers may be invalid and cause the dump to abort.
Query (0): is an invalid pointer
Connection ID (thread ID): 2
Status: NOT_KILLED

The manual page at http://dev.mysql.com/doc/mysql/en/crashing.html contains
information that should help you find out what is causing the crash.
2018-09-07T12:27:20.027024Z 0 [System] [MY-010116] [Server] /usr/sbin/mysqld (mysqld 8.0.12) starting as process 4161


I know this is all that is being added because I am adding a few blank lines to the log just before trying to launch MySQL and this code is all that comes up after my injected blank lines. 

I am running Ubuntu 18lts server. MySQL 5.7 rand fine and my database had no errors because I checked it before trying the upgrade.
I suspect this may be caused by a bug that happens when in-line upgrades go from 5.5 to 5.6 to 5.7 then finally 8.0.

The suggestion to deal with this is to run optomize table on every single table while in version 5.7. Once the 8.0 upgrade is attmpted, it is too late because you cannot go back.

I am giving up, rebuilding this server from scratch, then install 5.7 and perform the optomize table then try the upgrade to 8.0 again.

Good thing I have another 5.7 server running and a full backup of all the data.