strict aliasing violations.
Essentially, the problem is that large parts of the server were
developed in simpler times (last decades, pre C99 standard) when
strict aliasing and compilers supporting such optimizations were
rare to non-existent. Thus, when compiling the server with a modern
compiler that uses strict aliasing rules to perform optimizations,
there are several places in the code that might trigger undefined
behavior.
As evinced by some recent bugs, GCC does a somewhat good of job
misoptimizing such code, but on the other hand also gives warnings
about suspicious code. One problem is that the warnings aren't
always accurate, yet we can't afford to just shut them off as we
might miss real cases. False-positive cases are aggravated mostly
by casts that are likely to trigger undefined behavior.
The solution is to start a cleanup process focused on fixing and
reducing the amount of strict-aliasing related warnings produced
by GCC and others compilers. A good deal of noise reduction can
be achieved by just removing useless casts that are product of
historical cruft and are likely to trigger undefined behavior if
dereferenced.
client/mysql.cc:
Remove now-unnecessary casts.
Break up large strings.
client/mysql_upgrade.c:
Remove now-unnecessary casts.
client/mysqladmin.cc:
Remove now-unnecessary casts.
Break up large strings.
client/mysqlbinlog.cc:
Remove now-unnecessary casts.
client/mysqlcheck.c:
Remove now-unnecessary casts.
client/mysqldump.c:
Remove now-unnecessary casts.
client/mysqlimport.c:
Remove now-unnecessary casts.
client/mysqlshow.c:
Remove now-unnecessary casts.
client/mysqlslap.c:
Remove now-unnecessary casts.
client/mysqltest.cc:
Remove now-unnecessary casts.
extra/comp_err.c:
Remove now-unnecessary casts.
extra/my_print_defaults.c:
Remove now-unnecessary casts.
Break up large strings.
extra/mysql_waitpid.c:
Remove now-unnecessary casts.
extra/perror.c:
Remove now-unnecessary casts.
extra/resolve_stack_dump.c:
Remove now-unnecessary casts.
extra/resolveip.c:
Remove now-unnecessary casts.
include/my_getopt.h:
Use a void pointer type as the opaque type to avoid problems with type
incompatibility -- GCC issues warnings when the type name is not type
compatible with a operand. As a side bonus, a explicit cast won't be
necessary anymore.
include/sslopt-longopts.h:
Remove now-unnecessary casts.
Break up large strings.
mysys/my_getopt.c:
Update opaque type and introduce a type definition for the
argument to my_getopt_register_get_addr.
server-tools/instance-manager/options.cc:
Remove now-unnecessary casts.
sql/mysqld.cc:
Remove now-unnecessary casts.
Break up large strings.
Update mysql_getopt_value prototype (the old prototype
was different from the definition anyway).
sql/sql_plugin.cc:
The type of a pointer to a function must be compatible with the
pointed-to function type, otherwise the behavior is undefined.
sql/table.cc:
The variable buf pointer to pointer to pointer to constant char
could improperly alias a incompatible type in call to fix_type_
pointers. Since this was actually dead code, it is simply removed.
sql/unireg.cc:
Remove call to get_form_pos. The code creates a new FRM file which
is always truncated and writes the form position as 0. Hence, no
need to retrieve it, we now for sure it is 0.
storage/archive/archive_reader.c:
Remove now-unnecessary casts.
storage/myisam/ft_nlq_search.c:
Read weight directly from the buffer.
storage/myisam/fulltext.h:
Add explanation about the type duality of a key buffer.
Add accessor macro to retrieve a FT float value.
storage/myisam/mi_test1.c:
Remove now-unnecessary casts.
storage/myisam/myisam_ftdump.c:
Read weight directly from the buffer.
storage/myisam/myisamchk.c:
Remove now-unnecessary casts.
storage/myisam/myisamlog.c:
A pointer to char was used to alias a pointer to pointer to
unsigned char, thus violating strict aliasing rules.
storage/myisam/myisampack.c:
Remove now-unnecessary casts.
strings/decimal.c:
Remove aliasing violation, printing the value is enough for
debugging purposes.
tests/mysql_client_test.c:
Remove now-unnecessary casts.
- Ported relevant changes from the upstream version to not
break strict-aliasing rules and to fix compiler warnings and
and infinite loops caused by that issue.
- Fixed compilation with Honor_FLT_ROUNDS defined.
- Fixed an unused variable warning.
Add -Wall to gcc/g++
Fix most warnings reported in dbg and opt mode.
cmd-line-utils/libedit/filecomplete.c:
Remove unused auto variables.
configure.cmake:
Add -Wall to gcc.
extra/comp_err.c:
Cast to correct type.
extra/perror.c:
Fix segfault (but warnings about deprecated features remain)
extra/yassl/taocrypt/include/runtime.hpp:
Comparing two literals was reported as undefined behaviour.
include/my_global.h:
Add a template for aligning character buffers.
mysys/lf_alloc-pin.c:
Initialize pointer.
sql/mysqld.cc:
Use UNINIT_VAR rather than LINT_INIT.
sql/partition_info.cc:
Use UNINIT_VAR rather than LINT_INIT.
sql/rpl_handler.cc:
Use char[] rather than unsigned long[] array for placement buffer.
sql/spatial.cc:
Use char[] rather than unsigned void*[] array for placement buffer.
sql/spatial.h:
Use char[] rather than unsigned void*[] array for placement buffer.
sql/sql_partition.cc:
Initialize auto variable.
sql/sql_table.cc:
Initialize auto variables.
Add parens around assignment within if()
sql/sys_vars.cc:
Use UNINIT_VAR.
storage/innobase/os/os0file.c:
Init first slot in auto variable.
storage/myisam/mi_create.c:
Use UNINIT_VAR rather than LINT_INIT.
storage/myisam/mi_open.c:
Remove (wrong) casting.
storage/myisam/mi_page.c:
Remove (wrong) casting.
storage/myisam/mi_search.c:
Cast to uchar* rather than char*.
strings/ctype-ucs2.c:
Use UNINIT_VAR rather than LINT_INIT.
Add (uchar*) casting.
(make relies GNU extentions). The patch was partially
backport from 6.0.
Original comment:
bug#30708: make relies GNU extensions. Now that we no longer use
BitKeeper we can safely remove the SCCS handling with no loss of
functionality.
The failing assertion was written with the assumption that a NULL
string can never be passed to my_strtod(). However, an empty string
may be passed under some circumstances by passing str == NULL and
*end == NULL.
Fixed the assertion to take the above case into account.
mysql-test/r/func_misc.result:
Added a test case for bug #52165.
mysql-test/t/func_misc.test:
Added a test case for bug #52165.
strings/dtoa.c:
Fixed the assertion in my_strtod() to take the case of 'str == NULL
&& *end == NULL' into account.
- Fixing crash on attempt to create a fulltext index with an utf8mb4 column
- fixing wrong border width for supplementary characters in mysql client:
mysql --default-character-set=utf8mb4 -e "select concat(_utf32 0x20000,'a')"
Bug#51676 Server crashes on SELECT, ORDER BY on 'utf8mb4' column
An additional fix. We should use 0xFFFD as a weight for supplementary
characters, not the "weight for character U+FFFD".
Bug#51675 Server crashes on inserting 4 byte char. after ALTER TABLE to 'utf8mb4'
Bug#51676 Server crashes on SELECT, ORDER BY on 'utf8mb4' column
include/m_ctype.h:
Defining MY_CS_REPLACEMENT_CHARACTER
mysql-test/r/ctype_utf8mb4.result:
Adding tests
mysql-test/t/ctype_utf8mb4.test:
Adding tests
strings/ctype-uca.c:
Don't use UCA data for characters higher than 0xFFFF.
strings/ctype-ucs2.c:
Using newly defined MY_CS_REPLACEMENT_CHARACTER
strings/ctype-utf8.c:
Using newly defined MY_CS_REPLACEMENT_CHARACTER
Removing unesed variable "plane".
config/ac-macros/character_sets.m4:
- Adding configure definitions for utf8mb4, utf16, utf32
include/config-win.h:
- Enabling utf8mb4, utf16, utf32 in Windows build
include/m_ctype.h:
- Adding new flags
- Adding new shared functions prototypes
mysql-test/include/ctype_datetime.inc:
- Adding test to check that datetime functions
work with "real" multibyte character sets.
mysql-test/include/ctype_like.inc:
- Adding LIKE tests
mysql-test/include/have_utf16.inc:
New file
mysql-test/include/have_utf32.inc:
New file
mysql-test/include/have_utf8mb4.inc:
New file
mysql-test/r/ctype_ldml.result:
- Adding tests for utf8mb4, utf16, utf32
mysql-test/r/ctype_many.result:
- Adding tests to check superset/subset relations
between all Unicode character sets.
mysql-test/r/ctype_utf16.result:
New file
mysql-test/r/ctype_utf16_uca.result:
New file
mysql-test/r/ctype_utf32.result:
New file
mysql-test/r/ctype_utf32_uca.result:
New file
mysql-test/r/ctype_utf8.result:
- Adding tests for utf8mn3 alias
mysql-test/r/ctype_utf8mb4.result:
- Adding tests for utf8mb4
mysql-test/r/have_utf16.require:
New file
mysql-test/r/have_utf32.require:
New file
mysql-test/r/have_utf8mb4.require:
New file
mysql-test/std_data/Index.xml:
- Adding tests for loadable utf8m4, utf16, utf32 collations
mysql-test/suite/sys_vars/r/character_set_client_basic.result:
- Adding tests for utf16, utf32.
- Fixing new number of character sets
mysql-test/suite/sys_vars/r/character_set_connection_basic.result:
- Fixing new number of character sets
mysql-test/suite/sys_vars/r/character_set_database_basic.result:
- Fixing new number of character sets
mysql-test/suite/sys_vars/r/character_set_filesystem_basic.result:
- Fixing new number of character sets
mysql-test/suite/sys_vars/r/character_set_results_basic.result:
- Fixing new number of character sets
mysql-test/suite/sys_vars/t/character_set_client_basic.test:
- Adding tests for new character sets
mysql-test/suite/sys_vars/t/character_set_connection_basic.test:
- Adding dependency on utf8mb4, utf16, utf32
mysql-test/suite/sys_vars/t/character_set_database_basic.test:
- Adding dependency on utf8mb4, utf16, utf32
mysql-test/suite/sys_vars/t/character_set_filesystem_basic.test:
- Adding dependency on utf8mb4, utf16, utf32
mysql-test/suite/sys_vars/t/character_set_results_basic.test:
- Adding dependency on utf8mb4, utf16, utf32
mysql-test/t/ctype_ldml.test:
- Adding tests for dynamic utf8mb4, utf16, utf32 collations
mysql-test/t/ctype_many.test:
- Adding tests to check superset/subset relations
between all Unicode character sets
mysql-test/t/ctype_utf16.test:
New file
mysql-test/t/ctype_utf16_uca.test:
New file
mysql-test/t/ctype_utf32.test:
New file
mysql-test/t/ctype_utf32_uca.test:
New file
mysql-test/t/ctype_utf8.test:
- Adding tests for utf8mb4 alias
mysql-test/t/ctype_utf8mb4.test:
New file
mysys/charset-def.c:
- Adding initialization of utf8mb4, utf16, utf32 built-int collations
mysys/charset.c:
- Adding initialization of utf8mb4, utf16, utf32 dynamic collations
sql/field.cc:
- Fixing "truncated" error with datetime functions:
Force conversion in case of non-ascii character sets.
sql/item.cc:
- Adding superset/subset relation check for utf8mb4/utf8
sql/item_strfunc.cc:
- Fixing a problem with CHAR(x USING utf32)
sql/sql_string.cc:
- Fixing problems with zero padding for UTF32
sql/sql_table.cc:
- Fixing buffer size, to make utf32 comma fit.
strings/ctype-mb.c:
- Making handlers for multi-byte binary collations public
strings/ctype-uca.c:
- Adding definitions for utf8mb4, utf16, utf32 UCA collations
strings/ctype-ucs2.c:
- Adding functions which are shared between ucs2, utf16, utf32
- Ading utf16 implementation
- Adding utf32 implementation
strings/ctype-utf8.c:
- Adding functions shared between utf8 and utf8mb4
- Adding implementation of utf8mb4
Conflicts:
Text conflict in .bzr-mysql/default.conf
Text conflict in mysql-test/suite/rpl/r/rpl_loaddata_fatal.result
Text conflict in mysql-test/suite/rpl/r/rpl_stm_log.result
Text conflict in mysql-test/t/mysqlbinlog.test
Text conflict in sql/sql_acl.cc
Text conflict in sql/sql_servers.cc
Text conflict in sql/sql_update.cc
Text conflict in support-files/mysql.spec.sh
32bit builds with the --enable-assembler flag (enabled by default)
fail with an error message: undefined reference to `strmov_overlapp'.
Since the fix for bug 48866 we use a home-grown strmov function
instead of the ctpcpy function, but the source file for this
function was missed in the Makefile.am.
The strings/Makefile.am file has been modified to include strmov.c
file into ASSEMBLER_x86 and ASSEMBLER_sparc32 sections.
strings/Makefile.am:
Bug #49955: ld error message: undefined reference to `strmov_overlapp'
The strings/Makefile.am file has been modified to include
strmov.c file into ASSEMBLER_x86 and ASSEMBLER_sparc32 sections.
- backported code that handles %f/%g arguments in
my_vsnprintf.c from 6.0
- backported %f/%g tests in unittest/mysys/my_vsnprintf-t.c
from 6.0
- replaced snprintf("%g") in sql/set_var.cc with my_gcvt()
- removed unnecessary "--replace-result"s for Windows in
mysql-test/suite/sys_vars/t/long_query_time_basic.test
- some test results adjustments
to string conversions and vice versa"
Initial import of the dtoa.c code and custom wrappers around it
to allow its usage from the server code.
Conversion of FLOAT/DOUBLE values to DECIMAL ones or strings
and vice versa has been significantly reworked. As the new
algoritms are more precise than the older ones, results of such
conversions may not always match those obtained from older
server versions. This in turn may break compatibility for some
applications.
This patch also fixes the following bugs:
- bug #12860 "Difference in zero padding of exponent between
Unix and Windows"
- bug #21497 "DOUBLE truncated to unusable value"
- bug #26788 "mysqld (debug) aborts when inserting specific
numbers into char fields"
- bug #24541 "Data truncated..." on decimal type columns
without any good reason"
Bug#16565 mysqld --help --verbose does not order variablesBug#20413 sql_slave_skip_counter is not shown in show variables
Bug#20415 Output of mysqld --help --verbose is incomplete
Bug#25430 variable not found in SELECT @@global.ft_max_word_len;
Bug#32902 plugin variables don't know their names
Bug#34599 MySQLD Option and Variable Reference need to be consistent in formatting!
Bug#34829 No default value for variable and setting default does not raise error
Bug#34834 ? Is accepted as a valid sql mode
Bug#34878 Few variables have default value according to documentation but error occurs
Bug#34883 ft_boolean_syntax cant be assigned from user variable to global var.
Bug#37187 `INFORMATION_SCHEMA`.`GLOBAL_VARIABLES`: inconsistent status
Bug#40988 log_output_basic.test succeeded though syntactically false.
Bug#41010 enum-style command-line options are not honoured (maria.maria-recover fails)
Bug#42103 Setting key_buffer_size to a negative value may lead to very large allocations
Bug#44691 Some plugins configured as MYSQL_PLUGIN_MANDATORY in can be disabled
Bug#44797 plugins w/o command-line options have no disabling option in --help
Bug#46314 string system variables don't support expressions
Bug#46470 sys_vars.max_binlog_cache_size_basic_32 is broken
Bug#46586 When using the plugin interface the type "set" for options caused a crash.
Bug#47212 Crash in DBUG_PRINT in mysqltest.cc when trying to print octal number
Bug#48758 mysqltest crashes on sys_vars.collation_server_basic in gcov builds
Bug#49417 some complaints about mysqld --help --verbose output
Bug#49540 DEFAULT value of binlog_format isn't the default value
Bug#49640 ambiguous option '--skip-skip-myisam' (double skip prefix)
Bug#49644 init_connect and \0
Bug#49645 init_slave and multi-byte characters
Bug#49646 mysql --show-warnings crashes when server dies
CMakeLists.txt:
Bug#44691 Some plugins configured as MYSQL_PLUGIN_MANDATORY in can be disabled
client/mysql.cc:
don't crash with --show-warnings when mysqld dies
config/ac-macros/plugins.m4:
Bug#44691 Some plugins configured as MYSQL_PLUGIN_MANDATORY in can be disabled
include/my_getopt.h:
comments
include/my_pthread.h:
fix double #define
mysql-test/mysql-test-run.pl:
run sys_vars suite by default
properly recognize envirinment variables (e.g. MTR_MAX_SAVE_CORE) set to 0
escape gdb command line arguments
mysql-test/suite/sys_vars/r/rpl_init_slave_func.result:
init_slave+utf8 bug
mysql-test/suite/sys_vars/t/rpl_init_slave_func.test:
init_slave+utf8 bug
mysys/my_getopt.c:
Bug#34599 MySQLD Option and Variable Reference need to be consistent in formatting!
Bug#46586 When using the plugin interface the type "set" for options caused a crash.
Bug#49640 ambiguous option '--skip-skip-myisam' (double skip prefix)
mysys/typelib.c:
support for flagset
sql/ha_ndbcluster.cc:
backport from telco tree
sql/item_func.cc:
Bug#49644 init_connect and \0
Bug#49645 init_slave and multi-byte characters
sql/sql_builtin.cc.in:
Bug#44691 Some plugins configured as MYSQL_PLUGIN_MANDATORY in can be disabled
sql/sql_plugin.cc:
Bug#44691 Some plugins configured as MYSQL_PLUGIN_MANDATORY in can be disabled
Bug#32902 plugin variables don't know their names
Bug#44797 plugins w/o command-line options have no disabling option in --help
sql/sys_vars.cc:
all server variables are defined here
storage/myisam/ft_parser.c:
remove unnecessary updates of param->quot
storage/myisam/ha_myisam.cc:
myisam_* variables belong here
strings/my_vsnprintf.c:
%o and %llx
unittest/mysys/my_vsnprintf-t.c:
%o and %llx tests
vio/viosocket.c:
bugfix: fix @@wait_timeout to work with socket timeouts (vs. alarm thread)
strmov() is not guaranteed to work correctly on overlapping
source and destination buffers. On some OSes it may work,
but Fedora 12 has a stpcpy() that's not working correctly
on overlapping buffers.
Fixed to use the overlap-safe version of strmov instead.
Re-vitalized the overlap-safe version of strmov.
