2002-12-07 Ravi Pratap <ravi@ximian.com>

2002-12-07  Ravi Pratap  <ravi@ximian.com>

	* attribute.cs (Attribute.ApplyAttributes) : Keep track of which attribute
	types have been emitted for a given element and flag an error
	if something which does not have AllowMultiple set is used more
	than once.

	* typemanager.cs (RegisterAttributeAllowMultiple): Keep track of
	attribute types and their corresponding AllowMultiple properties

	(AreMultipleAllowed): Check the property for a given type.

	* attribute.cs (Attribute.ApplyAttributes): Register the AllowMultiple
	property in the case we have a TypeContainer.

	(Attributes.AddAttribute): Detect duplicates and just skip on
	adding them. This trivial fix catches a pretty gross error in our
	attribute emission - global attributes were being emitted twice!

	Bugzilla bug #33187 is now fixed.

svn path=/trunk/mcs/; revision=9440