don't replace with ?, just skip it
Merge branch 'PHP-5.5' into PHP-5.6

Conflicts:
	ext/mysqli/mysqli_api.c
add info: empty strings are interned
Emit a warning in case of unallowed characters. Fix another place this
code is used - reuse
Merge branch 'PHP-5.5' into PHP-5.6
Fixes after merge
Remove unnecessary check

In case of an update the key already existed, so the next free
element can not change.
Add helper function for updating bucket contents
Make zend_hash_apply_deleter() void, to allow reuse

Also remove lies in the comment above the function. apply_deleter
is not safe against modification, if the modification involves
removing the next bucket.

Also modified the implementation of zend_hash_graceful_destroy()
to be fully graceful (the reverse variant already was).
Rename+move zend_hash_apply_deleter and reuse it

The interruption handling was normalized to wrap the entire deletion
operation (instead of leaving out the destructor call and/or the
deallocation) per the recommendation of somebody (don't remember who)
familiar with zend signals.

There is an always-inlined variant of the function for use in
the main deletion function, to ensure there is no performance
impact.
Revert "Add helper function for updating bucket contents"

Reverting this for now, because it would require further changes
thanks to the zend signals tsrms-but-only-sometimes awesomeness.
Merge branch 'PHP-5.6' of git.php.net:php-src into PHP-5.6
Merge remote-tracking branch 'origin/PHP-5.6' into str_size_and_int64_56_backport

* origin/PHP-5.6:
  Revert "Add helper function for updating bucket contents"
  Rename+move zend_hash_apply_deleter and reuse it
  Make zend_hash_apply_deleter() void, to allow reuse
  Add helper function for updating bucket contents
  Remove unnecessary check
  Fixes after merge
  Emit a warning in case of unallowed characters. Fix another place this code is used - reuse
  add info: empty strings are interned
  don't replace with ?, just skip it

Conflicts:
	Zend/zend_hash.c
	ext/mysqlnd/mysqlnd.c
fix signature
fix C89 compat
Merge remote-tracking branch 'origin/PHP-5.6' into str_size_and_int64_56_backport

* origin/PHP-5.6:
  fix C89 compat