Issue 1486:  LOCATE_FORWARD_PERM and hash() (interop)
Source:  (, )
Nature:  Uncategorized Issue
Severity: 
Summary: Summary: With GIOP 1.2, we added LOCATE_FORWARD_PERM to the protocol, which
 permanently replaces an IOR with a different one. I believe we shouldn"t
 have done this because it creates an internal inconsistency. The
 Object::hash() operation requires that the hash value for a reference
 must be immutable during its life time. (Unfortunately, "life time" isn"t
 well-defined.)
 

Resolution: resolved
Revised Text: Since these fixes have not arrived, the resolution proposed is to depricated use of LOCATE_FORWARD_PERM 
Revised Text: 
Add the following statement to 13.4.3.2 at the end of the bullet list containing the explanation for LOCATE_FORWARD_PERM: 
" 
Note: Usage of LOCATE_FORWARD_PERM is now depricated, due to problems it causes with the semantics of the
Object::hash() operation.   LOCATE_FORWARD_PERM features could be removed from some future GIOP versions if
solutions to these problems are not provided . 
" 
Add the following statement to 13.4.6.1 at the end of the bullet list containing the explanation for OBJECT_FORWARD_PERM: 
" 
Note: Usage of OBJECT_FORWARD_PERM is now depricated, due to problems it causes with the semantics of the
Object::hash() operation.   OBJECT_FORWARD_PERM features could be removed from some future GIOP versions if
solutions to these problems are not provided. 
" 

In 15.6, immediately after the paragraph beginning "For GIOP version 1.2, the usage of LOCATION_FORWARD_PERM
(OBJECT_FORWARD_PERM) behaves like ...", add the following 
" 
Note: Usage of LOCATE_FORWARD_PERM and OBJECT_FORWARD_PERM is now depricated, due to problems it causes
with the semantics of the Object::hash() operation.   LOCATE_FORWARD_PERM and OBJECT_FORWARD_PERM could
be removed from some future GIOP versions if solutions to these problems are not provided . 

Actions taken:
June 3, 1998: received issue
October 4, 2000: Approved by RTF in Vote 2
October 4, 2000: closed issue
Discussion: 
At the final meeting of the Interop2000 rtf, it was agreed that unless fixes to the identified problems could be found, use of locate
forward perm should be depricated. 

As a result of comments in vote 2, the wording of the future version message was modified from "will" to "could".
End of Annotations:=====

*ISSUE 57*

Section 2.2.2.3, UML diagram for Structural Features

The following UML classifiers describing BOCA meta-types have
attributes that are actually supposed to be 
relationships.  The following table specifies the meta-types that have
this problem and the problematic 
attributes:

BocaMeta-type
Attribute
Target BocaMeta-type
BocaStructuralFeature
computation
Expression
BocaStructuralFeature
constraint
BooleanExpression
BocaStructuralFeature
returned_type
Classifier
BocaRelationshipReference
with_respect_to
BocaRelationshipReference

Recommendation: Remove the attributes or mark them as derived
attributes. Draw the associations where 
practical.