Well, encryption research. RadioGatún (SHA-3’s direct predecessor), for example, allows the bit width to be any number between 1 and 64, so this will allow us to see how, say, 29-bit integers work with this algorithm.
Most cryptographic algorithms (notably RC5 and RC6, but also Rijndael/AES) can be extended in to 128-bit word size variants, and having guaranteed support for 128-bit integers in C would be useful to see how these variants act, and run programs to evaluate their security margin.
Most cryptographic algorithms (notably RC5 and RC6, but also Rijndael/AES) can be extended in to 128-bit word size variants, and having guaranteed support for 128-bit integers in C would be useful to see how these variants act, and run programs to evaluate their security margin.