try to build tor-browser.git with clang's Code Flow Integrity option
I tried to build tor-browser.git using -fsanitize=cfi and I ran into the following bug that was reported recently: http://lists.llvm.org/pipermail/llvm-dev/2017-February/109861.html
Fortunately, it seems this bug has been fixed in clang 4.0. Binaries for clang 4.0.0 should be available in a few days so I will try again then.
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