I found a SILOptimizer problem.

main.swift

// `swiftc -Osize main.swift` then crash.
// Apple Swift version 5.2 (swiftlang-1103.0.32.1 clang-1103.0.32.29).

struct S {
}

struct T {
    let s: S
}

class C {
    func method() -> Any {
        let t = f()
        let r = (t != nil) ? 1 : nil
        return (r, t?.s)
    }

    func f() -> T? {
        return T(s: S())
    }
}

See https://bugs.swift.org/browse/SR-12495