[compiler-rt] [llvm] [msan] Add interceptors for fortified memory functions (__memcpy_chk, etc.) (PR #206702)

[Austin Schuh via llvm-commits]

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@@ -83,6 +92,34 @@
   }
 #endif
 
+// By default the fortified _chk variants behave like their plain counterparts;
+// the fortification bound (dst_size) is unused because the tool's own bounds
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AustinSchuh wrote:

Done.  Thanks!  I didn't see a great way to test that case.

https://github.com/llvm/llvm-project/pull/206702