Added missing `;' to DBUG_RETURN()

into mysql.com:/my/mysql-4.1

Fixes while reviewing new pushed code
NULL as argument to encrypt/decrypt should return NULL without a warning

into mysql.com:/my/mysql-4.1

into  mishka.local:/home/my/mysql-4.1

#9728  'Decreased functionality in "on duplicate key update
#8147  'a column proclaimed ambigous in INSERT ... SELECT .. ON DUPLICATE'

This ensures fields are uniquely qualified and also that one can't update other tables in the ON DUPLICATE KEY UPDATE part

into neptunus.(none):/home/msvensson/mysql/mysql-4.1

Moved the key statistics update to info().
The table is not locked in open(). This made wrong stats possible.

No test case for the test suite.
This happens only with heavy concurrency.
A test script is added to the bug report.

into mysql.com:/home/timka/mysql/src/4.1-virgin

into neptunus.(none):/home/msvensson/mysql/mysql-4.1

into mysql.com:/home/timka/mysql/src/4.1-virgin

into mysql.com:/Users/kent/mysql/bk/mysql-4.1

into mysql.com:/home/psergey/mysql-4.1-bug10151

  Fix for fix for bug #9728
  Error caused server hang on prepared insert ... select

  Might need a restart after test with special TZ
  Removed unused argument to run_mysqltest()

into mysql.com:/home/psergey/mysql-4.1-bug10151

into neptunus.(none):/home/msvensson/mysql/mysql-4.1

into  mishka.local:/home/my/mysql-4.1

into mysql.com:/home/timka/mysql/src/4.1-virgin

into mysql.com:/space/my/mysql-4.1

into mysql.com:/home/psergey/mysql-4.1-bug10151

into mysql.com:/home/timka/mysql/src/4.1-bug-11185

The source of the problem is in Field_longlong::cmp. If 'this' is
an unsigned number, the method casts both the current value, and
the constant that we compare with to an unsigned number. As a
result if the constant we compare with is a negative number, it
wraps to some unsigned number, and the comparison is incorrect.

When the optimizer chooses the "range" access method, this problem
causes handler::read_range_next to reject the current key when the
upper bound key is a negative number because handler::compare_key
incorrectly considers the positive and negative keys to be equal.

The current patch does not correct the source of the problem in
Field_longlong::cmp because it is not easy to propagate sign
information about the constant at query execution time. Instead
the patch changes the range optimizer so that it never compares
unsiged fields with negative constants. As an added benefit,
queries that do such comparisons will execute faster because
the range optimizer replaces conditions like:
(a) (unsigned_int [< | <=] negative_constant) == FALSE
(b) (unsigned_int [> | >=] negative_constant) == TRUE
with the corresponding constants.
In some cases this may even result in constant time execution.

into neptunus.(none):/home/msvensson/mysql/mysql-4.1

into mysql.com:/home/psergey/mysql-4.1-bug10151

into mdk10.(none):/home/reggie/bk/bug9148

into moonbone.local:/work/mysql-4.1-bug-8147

  Fix for fix for bug#9728 decreased functionality in "on duplicate key update"
  Have to return false to set flag for whole expression.

 - Importing the bug fixes by patch due to merge problems.

into neptunus.(none):/home/msvensson/mysql/bug10589