As a note to this while we're at define().

define() also seems to ignore if you declare a class constant like:
define('test::c', 'test');

Both with and without having a class called 'test' passes this, testing without the class 'test' like:
var_dump(test::c);

Will result in a fatal error: class 'test' not found. Testing it with a class called 'test' will issue a fatal error: undefined class constant 'c'.

If the class 'test' already have a constant called 'c' define() will still ignore it and var_dump() will return the real value of test::c.

now that namespace separator will be \, the fix is simple: grep for "::" and fail if a user tries to do it.

This bug has been fixed in CVS.

Snapshots of the sources are packaged every three hours; this change
will be in the next snapshot. You can grab the snapshot at
http://snaps.php.net/.
 
Thank you for the report, and for helping us make PHP better.

Reopened.
Patches for HEAD and 5_2 broke the build and have been reverted.

Code in ZendEngine2/zend_builtin_functions.c revision 1.277.2.12.2.25.2.52 checks if the class exists and creates the global constant with the name A::B if it does. But this constant is unreachable other than by get_defined_constants() because both constant("A::B") and A::B works with class constants.

<?php
class A {}
define("A::B", true);
echo constant("A::B"); // Fatal error: Undefined class constant 'B'
echo A::B; // Fatal error: Undefined class constant 'B'
?>

I suggest to issue an error if the constant name contains "::" regardless the class exists or not. The code would be even simpler.

This bug has been fixed in SVN.

Snapshots of the sources are packaged every three hours; this change
will be in the next snapshot. You can grab the snapshot at
http://snaps.php.net/.
 
Thank you for the report, and for helping us make PHP better.