Change Set File Out problem Problem 2

Tim Rowledge tim at sumeru.stanford.edu
Wed Nov 15 05:55:43 UTC 2000


Bob Arning <arning at charm.net> is widely believed to have written:


> 1. ClassX has 2 inst vars: 'a b' and methods that reference them
> 2. A new change set is started.
> 3. Methods referencing 'a' are removed and 'a' itself is removed.
> 4. A new inst var 'c' is added and methods created that reference it.
> 5. The change set is filed out.
> 6. The change set is filed in to another image. 
> 
> At this point, if the change set contains only the (final) definition of ClassX with 'b c', then when the class definition is compiled, all the methods referencing 'a' will be recompiled and either generate an error or bytecodes that don't work. Could be big trouble. Really big.
IIRC this used to be handled by the 'inst var' appearing in Undeclared.
Referential safety is conserved, the culprit methods are easy to find,
etc. Was it changed for some reason? Am I hallucinating again?

tim
-- 
Tim Rowledge, tim at sumeru.stanford.edu, http://sumeru.stanford.edu/tim
Strange OpCodes: CPP: Crush Plotter Pen





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