make handling of overflow and undefined results much more clear.   Patch by Eli Friedman, thanks!
make handling of overflow and undefined results much more clear.  
Patch by Eli Friedman, thanks!


git-svn-id: 0ff597fd157e6f4fc38580e8d64ab130330d2411@46428 91177308-0d34-0410-b5e6-96231b3b80d8

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