From: Shubham Bansal <illusionist.neo at gmail.com> Date: Wed, 15 Mar 2017 17:43:44 +0530 >> You can't truncate, but you'll have to build 64-bit ops using 32-bit registers. > > A small example would help a lot. You can simply perform 64-bit operations in C code and see what gcc outputs for that code on this 32-bit target.