Bug 186191 - Consider MasqueradesAsUndefinedObjectType
Summary: Consider MasqueradesAsUndefinedObjectType
Status: NEW
Alias: None
Product: WebKit
Classification: Unclassified
Component: JavaScriptCore (show other bugs)
Version: WebKit Nightly Build
Hardware: Unspecified Unspecified
: P2 Normal
Assignee: Nobody
URL:
Keywords:
Depends on:
Blocks:
 
Reported: 2018-06-01 05:16 PDT by Yusuke Suzuki
Modified: 2018-06-01 05:16 PDT (History)
5 users (show)

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Description Yusuke Suzuki 2018-06-01 05:16:10 PDT 
MasqueradesAsUndefined is crazy feature,

1. It is introduced for backward compatibility of `if (document.all)` thingy. It is unlikely that MasqueradesAsUndefined objects increases
2. MasqueradesAsUndefined is only used for HTMLAllCollection right now
3. HTMLAllCollection is ObjectType

So, what do we think of folding this information into JSType, and free up MasqueradesAsUndefined TypeInfo flag space?
We can introduce MasqueradesAsUndefinedObjectType for HTMLAllCollection.