mkdir build; cd build

cmake -DCONC_WITH_{UNITTEST,SSL}=OFF -DWITH_EMBEDDED_SERVER=OFF -DWITH_UNIT_TESTS=OFF -DCMAKE_BUILD_TYPE=Debug -DPLUGIN_{ARCHIVE,TOKUDB,MROONGA,OQGRAPH,ROCKSDB,CONNECT,SPIDER}=NO -DWITH_SAFEMALLOC=OFF -DWITH_{SSL,ZLIB}=system "$@" -DCMAKE_C{,XX}_FLAGS='-O2 -march=native' -DWITH_UBSAN=ON ..

make -j$(nproc)

cd mysql-test

nice ./mtr --parallel=$(($(nproc) * 3 / 2)) --force --retry=0 --max-test-fail=0 --big-test

grep 'log.*runtime error' var/*/log/mysqld*err*|cut -d: -f2-|sed -e 's/0x[0-9a-fA-F]*/0xXXX/'|sort|uniq -c|sort -nr

   1740 /mariadb/10.4/sql/log.cc:3812:25: runtime error: member access within address 0xXXX which does not point to an object of type 'xid_count_per_binlog'

   1740 /mariadb/10.4/sql/log.cc:3714:41: runtime error: member access within address 0xXXX which does not point to an object of type 'xid_count_per_binlog'

   1740 /mariadb/10.4/sql/log.cc:3694:29: runtime error: member access within address 0xXXX which does not point to an object of type 'xid_count_per_binlog'

        if (!(new_xid_list_entry = (xid_count_per_binlog *)

              my_multi_malloc(MYF(MY_WME),

                              &entry_mem, sizeof(xid_count_per_binlog),

                              &name_mem, len,

                              NULL)))

          goto err;

        memcpy(name_mem, log_file_name+off, len);

        new_xid_list_entry->binlog_name= name_mem;

        new_xid_list_entry->binlog_name_len= (int)len;

        new_xid_list_entry->xid_count= 0;

        new_xid_list_entry->notify_count= 0;

  struct xid_count_per_binlog : public ilink {

…

    xid_count_per_binlog();   /* Give link error if constructor used. */

  };

    xid_count_per_binlog() = delete;

diff --git a/sql/log.cc b/sql/log.cc

index 7f632b43cb6..9a5081ab94a 100644

--- a/sql/log.cc

+++ b/sql/log.cc

@@ -3684,13 +3684,13 @@ bool MYSQL_BIN_LOG::open(const char *log_name,

         size_t off= dirname_length(log_file_name);

         size_t len= strlen(log_file_name) - off;

         char *entry_mem, *name_mem;

-        if (!(new_xid_list_entry = (xid_count_per_binlog *)

-              my_multi_malloc(MYF(MY_WME),

-                              &entry_mem, sizeof(xid_count_per_binlog),

-                              &name_mem, len,

-                              NULL)))

+        if (!my_multi_malloc(MYF(MY_WME),

+                             &entry_mem, sizeof(xid_count_per_binlog),

+                             &name_mem, len,

+                             NULL)))

           goto err;

         memcpy(name_mem, log_file_name+off, len);

+        new_xid_list_entry = new (entry_mem) xid_count_per_binlog();

         new_xid_list_entry->binlog_name= name_mem;

         new_xid_list_entry->binlog_name_len= (int)len;

         new_xid_list_entry->xid_count= 0;