141614 2015-02-14 19:14:06 -0800 [iOS] Possible Block Leak WKAutoCorrectionData.autocorrectionContextHandler 2015-02-14 19:14:06 -0800 1 1 1 Unclassified WebKit WebKit2 528+ (Nightly build) Unspecified Unspecified NEW P2 Normal --- 1 joepeck webkit-unassigned enrica simon.fraser oldest_to_newest 1069254 0 joepeck 2015-02-14 19:14:06 -0800 * SUMMARY Possible Block Leak WKAutoCorrectionData.autocorrectionContextHandler. Auditing the code, it looks like this block can be assigned a copy that is never released by anyone: _autocorrectionData.autocorrectionContextHandler = [completionHandler copy]; _page->requestAutocorrectionContext([self](...) { _autocorrectionData.autocorrectionContextHandler([WKAutocorrectionContext autocorrectionContextWithData:beforeText markedText:markedText selectedText:selectedText afterText:afterText selectedRangeInMarkedText:NSMakeRange(location, length)]); }); Looks like we should be releasing (and probably niling) _autocorrectionData.autocorrectionContextHandler. Or better yet, don't store these on the struct at all, and just capture them inside the block/lambda. All of the blocks assigned to WKAutoCorrectionData have sketchy lifetimes. They can are always set on the struct without clearing any possible value that may have been there before. Is there a guarantee that they won't be overwritten?