[PATCH] PR20721: Don't let UBSan print inaccessible memory

[Alexander Potapenko]

LGTM

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Comment at: lib/sanitizer_common/sanitizer_win.cc:526
@@ +525,3 @@
+bool IsAccessibleMemoryRange(uptr beg, uptr size) {
+  UNIMPLEMENTED();
+}
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I suggest making this function always return true and adding a FIXME

http://reviews.llvm.org/D5253