#include #include typedef union MyUnion { double d; int64_t i; int64_t i2; int64_t i3; int64_t i4; int64_t i5; int64_t i6; int64_t i7; int64_t i8; int64_t i9; int64_t i10; int64_t i11; int64_t i12; } my_union; void foo(my_union in) { printf("%f, %lu\n", in.d, in.i); }