The 32-bit implementation does this, and it can cause crashes if we later repatch the code to allocate and store new Butterflies.
Created attachment 229331 [details] Patch
<rdar://problem/16513604>
Comment on attachment 229331 [details] Patch View in context: https://bugs.webkit.org/attachment.cgi?id=229331&action=review > Source/JavaScriptCore/ChangeLog:12 > + (JSC::JIT::emitWriteBarrier): We also weren't verify the base was a cell on 32-bit if /weren’t verify the/weren’t verifying that the/.
Comment on attachment 229331 [details] Patch R=me with MarkL's suggestion.
Committed r167288: <http://trac.webkit.org/changeset/167288>