int foo() { version(X86) asm { mov EAX, 42; } else static assert(0, "todo"); } ulong bar() { version(X86) asm { mov EAX, 0xFF; mov EDX, 0xAA; } else static assert(0, "todo"); } void main() { long l = 1; l = 2; l = 4; l = 8; assert(foo() == 42); assert(bar() == 0x000000AA000000FF); }