The crash during boot was caused by a DBUG_PRINT statement in fill_schema_schemata() (in
sql_show.cc). This DBUG_PRINT statement contained several instances of %s in the format
string and for one of these we gave a NULL pointer as the argument. This caused the
call to vsnprintf() to crash when running on Solaris.
The fix for this problem is to replace the call to vsnprintf() with my_vsnprintf()
which handles that a NULL pointer is passed as argumens for %s.
This patch also extends my_vsnprintf() to support %i in the format string.
Problem:
- ORDER BY for utf8mb4_bin, utf16_bin and utf32_bin returned
results in a wrong order, because old functions
(supporting only BMP range) were used to handle these collations.
- Additionally, utf16_bin did not sort supplementary characters
between U+D700 and U+E000, as WL#1213 specification specified.
Problem: The functions my_like_range_xxx() returned
badly formed maximum strings for Asian character sets,
which made problems for storage engines.
Fix:
- Removed a number my_like_range_xxx() implementations,
which were in fact dumplicate code pieces.
- Using generic my_like_range_mb() instead.
- Setting max_sort_char member properly for Asian character sets
- Adding unittest/strings/strings-t.c,
to test that my_like_range_xxx() return well-formed
min and max strings.
Notes:
- No additional tests in mysql/t/ available.
Old tests cover the affected code well enough.
* Fixed obvious errors (HAVE_BROKEN_PREAD is not true for on any
of systems we use, definitely not on HPUX)
* Remove other junk flags for OSX and HPUX
* Avoid checking type sizes in universal builds on OSX, again
(CMake2.8.0 fails is different architectures return different results)
* Do not compile template instantiation stuff unless
EXPLICIT_TEMPLATE_INSTANTIATION is used.
* Some cleanup (make gen_lex_hash simpler, avoid dependencies)
* Exclude some unused files from compilation (strtol.c etc)
Fix warnings flagged by the new warning option -Wunused-but-set-variable
that was added to GCC 4.6 and that is enabled by -Wunused and -Wall. The
option causes a warning whenever a local variable is assigned to but is
later unused. It also warns about meaningless pointer dereferences.
Apart strict-aliasing warnings, fix the remaining warnings
generated by GCC 4.4.4 -Wall and -Wextra flags.
One major source of warnings was the in-house function my_bcmp
which (unconventionally) took pointers to unsigned characters
as the byte sequences to be compared. Since my_bcmp and bcmp
are deprecated functions whose only difference with memcmp is
the return value, every use of the function is replaced with
memcmp as the special return value wasn't actually being used
by any caller.
There were also various other warnings, mostly due to type
mismatches, missing return values, missing prototypes, dead
code (unreachable) and ignored return values.
Although the C standard mandates that sprintf return the number
of bytes written, some very ancient systems (i.e. SunOS 4)
returned a pointer to the buffer instead. Since these systems
are not supported anymore and are hopefully long dead by now,
simply remove the portability wrapper that dealt with this
discrepancy. The autoconf check was causing trouble with GCC.
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.
- 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.
(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.
- 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".
