For big types, only use unpromoted arithmetic for types no larger than long for that system. Use explicit integer sizes in random test to avoid errors on 32 bit long systems.
Merge pull request #6583 from JuliaLang/anj/big32

Only use unpromoted arithmetic for types no larger than 32 bit on 32 bit systems. Use explicit integer sizes in random test to avoid errors on 32 bit systems.