How is this different from tools like Valgrind and Address Sanitizer?

> Fil-C is engineered to prevent memory safety bugs from being used for exploitation rather than just simply flagging them often enough to find bugs. This makes Fil-C different from AddressSanitizer, HWAsan, or MTE, which can all be bypassed by attackers. The key difference that makes this possible is that Fil-C is capability based (so each pointer knows what range of memory it may access, and how it may access it) rather than tag based (where pointer accesses are allowed if they hit valid memory).

Clang says "AddressSanitizer's runtime was not developed with security-sensitive constraints in mind and may compromise the security of the resulting executable", so it should not be used in production.

Valgrind has much worse performance (the manual claims 10-50x slowdown, plus it's effectively single-threaded), which is probably bad enough to make it unusable in production, and similarly will miss many memory safety bugs.