[clang] [compiler-rt] [llvm] [UBSan] Add -fsanitize=uninitialized-read check (ISO C 6.3.2.1p2) (PR #207529)

[Thurston Dang via cfe-commits]

================
@@ -0,0 +1,107 @@
+// Tests the opt-in MSan local-uninitialized-read check
----------------
thurstond wrote:

For good measure, a test in clang/test/Driver should verify that `clang -###` correctly dumps `-fsanitize-memory-local-address-never-taken`

https://github.com/llvm/llvm-project/pull/207529