去不匹配的类型uint64和int32

Question

I don't see what i'm doing wrong here with this error, both are of type syscall.Timeval Usec

Thanks

package common

import (
    "syscall"
)

func getUsecSince(oldTime syscall.Timeval) (result uint64) {
    now := syscall.Timeval{}
    syscall.Gettimeofday(&now)

    for now.Sec > oldTime.Sec {
        result += 1000000
        now.Sec--
    }
    return result + (now.Usec - oldTime.Usec)
}

./common.go:15: invalid operation: result + (now.Usec - oldTime.Usec) (mismatched types uint64 and int32)

Answer 1

Timeval.Usec is defined as int32. Maybe result should be also int32? Alternatively if you want to use uint64 you can cast it by uint64(now.Usec - oldTime.Usec).