[1.11>master] [MERGE #6267 @zenparsing] Prevent a use after free in memop
[1.11>master] [MERGE #6267 @zenparsing] Prevent a use after free in memop

Merge pull request #6267 from zenparsing:use-after-free-memop

Microsoft/ChakraCore,Microsoft/ChakraCore,Microsoft/ChakraCore,Microsoft/ChakraCore,Microsoft/ChakraCore,Microsoft/ChakraCore