[PATCH] Don't register and de-register all PassRegistrationListeners automatically

[Zachary Turner]

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Comment at: include/llvm/IR/LegacyPassNameParser.h:47
@@ -47,2 +46,3 @@
+  PassNameParser();
   virtual ~PassNameParser();
 
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David Blaikie wrote:
> should we just remove this dtor entirely? (I don't see any reason it needs to be virtual, and it doesn't do anything)
I kind of would rather leave it, if only because it's a nice place to drop a comment that explicitly explains the reasoning behind the asymmetry of not calling removeRegistrationListener, just to make sure we don't get back into this bind later in the future.

http://reviews.llvm.org/D4106