Drupal 6 enables E_DEPRECATED if it is not enabled yet :)

Not sure what we can do here.

Those test bots are configured (in php.ini) with:

error_reporting = E_ALL & ~E_DEPRECATED

for both Apache and CLI.

The test clients on Drupal 6 are using the Simpletest module from contrib. It ships with a patch that (I think) is applied after Drupal 6 is downloaded. (I think, because I cannot make sense of the PIFR code base). This patch replaces the error handler of Drupal 6 with a backport from D7:

+function _drupal_error_handler($error_level, $message, $filename, $line, $context) {
+  if ($error_level & error_reporting()) {
+    ...
+  }
+}

This apparently respects the error_reporting() settings. So I'm not sure where to look after that.

The problem is actually in core:

// Hide E_DEPRECATED messages.
if (defined('E_DEPRECATED')) {
  error_reporting(error_reporting() ^ E_DEPRECATED);
}

This actually enables E_DEPRECATED if it is not already enabled :)

My bad, I RTBC-ed the faulty patch.

Nothing better then a little irony.

*blush*

Here is the correct patch. Sorry about that...

Crosspost

omg. Double crosspost :)

Committed, thanks. Happy testing.