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A comment on A problem with LLVM's undef. Parent comment

Re:A problem with LLVM's undef by sanjoy_das on Wednesday December 30, 2015 @07:29AM (#10811801)
Interesting observation -- just because I've checked `%i` is within array bounds, doesn't mean `a[%i]` is safe to access, since `%i` could be `undef` and pass the range check spuriously.
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Re:A problem with LLVM's undef by kzrdude on Friday January 01, 2016 @11:53AM (#10822345)
Yeah. And range checks are used to take subslices, so you can take a "sub"slice that's half the memory space, and you have unchecked access to everything after that point :-)
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