In DwarfEHPrepare, after all passes are run, RewindFunction may be a dangling pointer to a dead function. To make sure it's valid, doFinalization nullptrs RewindFunction just like the constructor and so it will be found on next run.
In DwarfEHPrepare, after all passes are run, RewindFunction may be a dangling
pointer to a dead function. To make sure it's valid, doFinalization nullptrs
RewindFunction just like the constructor and so it will be found on next run.



git-svn-id: 0ff597fd157e6f4fc38580e8d64ab130330d2411@217737 91177308-0d34-0410-b5e6-96231b3b80d8

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