Description:
Trying to learn Replication, source code.
Reading book, "Expert MySQL" by Charles Bell.
Chapter 8, "Extending MySQL High Availability" -> page 310, "Extending Replication".
Where we should add new command -> "SQLCOM_STOP_SLAVES" executed on master and causing to STOP IO_THREAD on all slaves.
After adding necessary things into:
sql/lex.h
sql/sql_cmd.h
sql/sql_yacc.h
sql/sql_parse.cc
Resulted with:
Scanning dependencies of target sql
[ 54%] Building CXX object sql/CMakeFiles/sql.dir/sql_parse.cc.o
[ 54%] Building CXX object sql/CMakeFiles/sql.dir/mysqld.cc.o
In file included from /home/sh/MySQLPakcages/mysql-5.6.32/include/my_compiler.h:151:0,
from /home/sh/MySQLPakcages/mysql-5.6.32/include/my_global.h:473,
from /home/sh/MySQLPakcages/mysql-5.6.32/sql/mysqld.cc:17:
/home/sh/MySQLPakcages/mysql-5.6.32/sql/mysqld.cc: In function ‘int init_common_variables()’:
/home/sh/MySQLPakcages/mysql-5.6.32/include/my_attribute.h:38:42: error: size of array ‘compile_time_assert’ is negative
# define MY_ATTRIBUTE(A) __attribute__(A)
^
/home/sh/MySQLPakcages/mysql-5.6.32/include/my_global.h:377:52: note: in expansion of macro ‘MY_ATTRIBUTE’
typedef char compile_time_assert[(X) ? 1 : -1] MY_ATTRIBUTE((unused)); \
^
/home/sh/MySQLPakcages/mysql-5.6.32/sql/mysqld.cc:3871:3: note: in expansion of macro ‘compile_time_assert’
compile_time_assert(sizeof(com_status_vars)/sizeof(com_status_vars[0]) - 1 ==
^
sql/CMakeFiles/sql.dir/build.make:3581: recipe for target 'sql/CMakeFiles/sql.dir/mysqld.cc.o' failed
make[2]: *** [sql/CMakeFiles/sql.dir/mysqld.cc.o] Error 1
CMakeFiles/Makefile2:5192: recipe for target 'sql/CMakeFiles/sql.dir/all' failed
make[1]: *** [sql/CMakeFiles/sql.dir/all] Error 2
Makefile:160: recipe for target 'all' failed
make: *** [all] Error 2
Inside sq/sql_cmd.h there is a comment:
/*
When a command is added here, be sure it's also added in mysqld.cc
in "struct show_var_st status_vars[]= {" ...
*/
It took me some time to figure out that instead of status_vars[] command should be added into SHOW_VAR com_status_vars[]=
Also comment indicates struct show_var_st status_vars[] inside sql/mysqld.cc which is in fact SHOW_VAR status_vars[] -> typedef struct st_mysql_show_var SHOW_VAR(sql/sql_show.h) -> struct st_mysql_show_var {
const char *name;
char *value;
enum enum_mysql_show_type type;
};(include/mysql/plugin.h)
How to repeat:
The main reason for report is replacing comment with new one, to be clear for beginners.
Suggested fix:
Replace comment with:
/*
When a command is added here, be sure it's also added in mysqld.cc
in " struct st_mysql_show_var com_status_vars[]= {" ...
*/
Description: Trying to learn Replication, source code. Reading book, "Expert MySQL" by Charles Bell. Chapter 8, "Extending MySQL High Availability" -> page 310, "Extending Replication". Where we should add new command -> "SQLCOM_STOP_SLAVES" executed on master and causing to STOP IO_THREAD on all slaves. After adding necessary things into: sql/lex.h sql/sql_cmd.h sql/sql_yacc.h sql/sql_parse.cc Resulted with: Scanning dependencies of target sql [ 54%] Building CXX object sql/CMakeFiles/sql.dir/sql_parse.cc.o [ 54%] Building CXX object sql/CMakeFiles/sql.dir/mysqld.cc.o In file included from /home/sh/MySQLPakcages/mysql-5.6.32/include/my_compiler.h:151:0, from /home/sh/MySQLPakcages/mysql-5.6.32/include/my_global.h:473, from /home/sh/MySQLPakcages/mysql-5.6.32/sql/mysqld.cc:17: /home/sh/MySQLPakcages/mysql-5.6.32/sql/mysqld.cc: In function ‘int init_common_variables()’: /home/sh/MySQLPakcages/mysql-5.6.32/include/my_attribute.h:38:42: error: size of array ‘compile_time_assert’ is negative # define MY_ATTRIBUTE(A) __attribute__(A) ^ /home/sh/MySQLPakcages/mysql-5.6.32/include/my_global.h:377:52: note: in expansion of macro ‘MY_ATTRIBUTE’ typedef char compile_time_assert[(X) ? 1 : -1] MY_ATTRIBUTE((unused)); \ ^ /home/sh/MySQLPakcages/mysql-5.6.32/sql/mysqld.cc:3871:3: note: in expansion of macro ‘compile_time_assert’ compile_time_assert(sizeof(com_status_vars)/sizeof(com_status_vars[0]) - 1 == ^ sql/CMakeFiles/sql.dir/build.make:3581: recipe for target 'sql/CMakeFiles/sql.dir/mysqld.cc.o' failed make[2]: *** [sql/CMakeFiles/sql.dir/mysqld.cc.o] Error 1 CMakeFiles/Makefile2:5192: recipe for target 'sql/CMakeFiles/sql.dir/all' failed make[1]: *** [sql/CMakeFiles/sql.dir/all] Error 2 Makefile:160: recipe for target 'all' failed make: *** [all] Error 2 Inside sq/sql_cmd.h there is a comment: /* When a command is added here, be sure it's also added in mysqld.cc in "struct show_var_st status_vars[]= {" ... */ It took me some time to figure out that instead of status_vars[] command should be added into SHOW_VAR com_status_vars[]= Also comment indicates struct show_var_st status_vars[] inside sql/mysqld.cc which is in fact SHOW_VAR status_vars[] -> typedef struct st_mysql_show_var SHOW_VAR(sql/sql_show.h) -> struct st_mysql_show_var { const char *name; char *value; enum enum_mysql_show_type type; };(include/mysql/plugin.h) How to repeat: The main reason for report is replacing comment with new one, to be clear for beginners. Suggested fix: Replace comment with: /* When a command is added here, be sure it's also added in mysqld.cc in " struct st_mysql_show_var com_status_vars[]= {" ... */