deprecated function warning improvement

[hakre]

Knee-deep in tests I ran over this:

Since PHP 4.3 we have a nice function called debug_backtrace() that can improve the message thrown out in _deprecated_function() a lot by adding information about the context (e.g. file and line) where a deprecated function was originally called.

In conjunction with WP_DEBUG a real time saver. Simple and smooth. Patch is against fresh trunk.

Example output after patch:

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Notice: get_settings is deprecated since version 2.1! Use get_option() instead. Called in file wp-content/themes/oldtheme/functions.php on line 5.

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Since we're globally in testing these days I can only suggest to give this a shot and put this ticket 3.0 out of the standard order. If a core dev is not confident with that, please put on a later version.

[nacin]

Some people run WP_DEBUG on production servers. A plugin can easily hook in and do this, we won't be adding the performance hit into core though.

[hakre]

Well I dunno wether performance is a real issue here. I think about adding that functionality to an error reporter component then. Thanks for taking the look into it.

[strider72]

There's a plugin for that!

​http://striderweb.com/nerdaphernalia/features/wp-log-deprecated-calls/

[ocean90]

#35849 was marked as a duplicate.

[ocean90]

#36565 was marked as a duplicate.