[DRAFT}use-of-uninitialized-value in process_dbl_arg

SET GLOBAL innodb_max_dirty_pages_pct_lwm=28;

SET GLOBAL innodb_max_dirty_pages_pct=20;

==3170063==WARNING: MemorySanitizer: use-of-uninitialized-value

    #0 0x5b9643b5c16b in process_dbl_arg /test/10.11_dbg_san/strings/my_vsnprintf.c:341:10

    #1 0x5b9643b5c16b in my_vsnprintf_ex /test/10.11_dbg_san/strings/my_vsnprintf.c:743:11

    #2 0x5b96424283bc in push_warning_printf(THD*, Sql_state_errno_level::enum_warning_level, unsigned int, char const*, ...) /test/10.11_dbg_san/sql/sql_error.cc:787:3

    #3 0x5b964303e693 in innodb_max_dirty_pages_pct_update(THD*, st_mysql_sys_var*, void*, void const*) /test/10.11_dbg_san/storage/innobase/handler/ha_innodb.cc:17459:3

    #4 0x5b964258558a in sys_var_pluginvar::global_update(THD*, set_var*) /test/10.11_dbg_san/sql/sql_plugin.cc:3694:3

    #5 0x5b96420e9ab6 in sys_var::update(THD*, set_var*) /test/10.11_dbg_san/sql/set_var.cc:209:12

    #6 0x5b96420eddd2 in set_var::update(THD*) /test/10.11_dbg_san/sql/set_var.cc:868

    #7 0x5b96420ed002 in sql_set_variables(THD*, List<set_var_base>*, bool) /test/10.11_dbg_san/sql/set_var.cc:749:20

    #8 0x5b964250e19d in mysql_execute_command(THD*, bool) /test/10.11_dbg_san/sql/sql_parse.cc:5209:9

    #9 0x5b9642500d1f in mysql_parse(THD*, char*, unsigned int, Parser_state*) /test/10.11_dbg_san/sql/sql_parse.cc:8221:18

    #10 0x5b96424fa766 in dispatch_command(enum_server_command, THD*, char*, unsigned int, bool) /test/10.11_dbg_san/sql/sql_parse.cc:1924:7

    #11 0x5b96425017e4 in do_command(THD*, bool) /test/10.11_dbg_san/sql/sql_parse.cc:1434:17

    #12 0x5b96429c737c in do_handle_one_connection(CONNECT*, bool) /test/10.11_dbg_san/sql/sql_connect.cc:1475:11

    #13 0x5b96429c6d17 in handle_one_connection /test/10.11_dbg_san/sql/sql_connect.cc:1387:5

    #14 0x7e1ce989caa3 in start_thread nptl/pthread_create.c:447:8

    #15 0x7e1ce9929c6b in clone3 misc/../sysdeps/unix/sysv/linux/x86_64/clone3.S:78

  Uninitialized value was stored to memory at

    #0 0x5b9643b5c164 in my_vsnprintf_ex /test/10.11_dbg_san/strings/my_vsnprintf.c:742:10

  Uninitialized value was created by an allocation of 'yyvsa' in the stack frame

    #0 0x5b96422c299f in MYSQLparse(THD*) /test/10.11_dbg_san/sql/yy_mariadb.cc:29480:5

SUMMARY: MemorySanitizer: use-of-uninitialized-value /test/10.11_dbg_san/strings/my_vsnprintf.c:341:10 in process_dbl_arg

Exiting

260617 15:41:12 [ERROR] /test/MSAN_MD170626-mariadb-10.11.19-linux-x86_64-dbg/bin/mariadbd got signal 6 ;

Sorry, we probably made a mistake, and this is a bug.

Your assistance in bug reporting will enable us to fix this for the next release.

To report this bug, see https://mariadb.com/docs/general-resources/community/community/bug-tracking/reporting-bugs about how to report

a bug on https://jira.mariadb.org/.

Please include the information from the server start above, to the end of the

information below.

Server version: 10.11.19-MariaDB-debug source revision: b1e62d5e530243456338e44be064952a53062fd5

The information page at https://mariadb.com/docs/server/reference/product-development/mariadb-fault-finding/how-to-produce-a-full-stack-trace-for-mariadbdcontains instructions to obtain a better version of the backtrace below.

Following these instructions will help MariaDB developers provide a fix quicker.

Attempting backtrace. Include this in the bug report.

(note: Retrieving this information may fail)

Thread pointer: 0x72b000126018

stack_bottom = 0x7e1c1ee02000 thread_stack 0x200000

/test/MSAN_MD170626-mariadb-10.11.19-linux-x86_64-dbg/bin/mariadbd(___interceptor_backtrace+0xd6)[0x5b9641a5a776]

mysys/stacktrace.c:216(my_print_stacktrace)[0x5b9643a17114]

sql/signal_handler.cc:0(handle_fatal_signal)[0x5b9642004913]

crtstuff.c:0(SignalHandler(int))[0x5b9641a8e52d]

libc_sigaction.c:0(__restore_rt)[0x7e1ce9845330]

nptl/pthread_kill.c:44(__pthread_kill_implementation)[0x7e1ce989eb2c]

posix/raise.c:27(__GI_raise)[0x7e1ce984527e]

stdlib/abort.c:81(__GI_abort)[0x7e1ce98288ff]

crtstuff.c:0(__sanitizer::Atexit(void (*)()))[0x5b9641a18060]

crtstuff.c:0(__sanitizer::Die())[0x5b9641a15dd2]

/test/MSAN_MD170626-mariadb-10.11.19-linux-x86_64-dbg/bin/mariadbd(+0xfe2757)[0x5b9641a2d757]

strings/my_vsnprintf.c:338(my_vsnprintf_ex)[0x5b9643b5c16c]

sql/sql_error.cc:0(push_warning_printf(THD*, Sql_state_errno_level::enum_warning_level, unsigned int, char const*, ...))[0x5b96424283bd]

handler/ha_innodb.cc:0(innodb_max_dirty_pages_pct_update(THD*, st_mysql_sys_var*, void*, void const*))[0x5b964303e694]

sql/sql_plugin.cc:3695(sys_var_pluginvar::global_update(THD*, set_var*))[0x5b964258558b]

sql/set_var.cc:0(sys_var::update(THD*, set_var*))[0x5b96420e9ab7]

sql/set_var.cc:868(set_var::update(THD*))[0x5b96420eddd3]

sql/set_var.cc:749(sql_set_variables(THD*, List<set_var_base>*, bool))[0x5b96420ed003]

sql/sql_parse.cc:0(mysql_execute_command(THD*, bool))[0x5b964250e19e]

sql/sql_parse.cc:0(mysql_parse(THD*, char*, unsigned int, Parser_state*))[0x5b9642500d20]

sql/sql_parse.cc:0(dispatch_command(enum_server_command, THD*, char*, unsigned int, bool))[0x5b96424fa767]

sql/sql_parse.cc:1436(do_command(THD*, bool))[0x5b96425017e5]

sql/sql_connect.cc:1475(do_handle_one_connection(CONNECT*, bool))[0x5b96429c737d]

sql/sql_connect.cc:0(handle_one_connection)[0x5b96429c6d18]

nptl/pthread_create.c:447(start_thread)[0x7e1ce989caa4]

x86_64/clone3.S:80(clone3)[0x7e1ce9929c6c]

Connection ID (thread ID): 4

Status: NOT_KILLED

Query (0x70b000005830): SET GLOBAL innodb_max_dirty_pages_pct=20