When generating C you can quite easily cast all signed to unsigned, do the operation, and cast back, if you want to avoid signed overflow.
Using int32_t and uint32_t, try adding -2147483648 and -1. The arithmetic result should be -2147483649, but a program converting back and forth between signed and unsigned will produce 2147483647 -- wrong answer and wrong sign.
Of course you will never be able to obtain an unrepresentable value (such as -2147483649) through a workaround, and if you cast back to signed you get the wrapped result (which, indeed, may have an unexpected sign). But the point of transpiling to operations on unsigned numbers is to avoid UB, not to escape basic computational bounds.