go-fuzz-build fails when 'fmt' is not imported

[jscrockett01]

I stumbled across this bug and workaround. When running go-fuzz-build against a package that does not import "fmt" I get the following error:

code:

package fuzz

func Fuzz(buf []byte) int {
	switch len(buf) {
	case 5:
		panic("crash")
	case 7:
		return 1
	}
	return 0
}

error:

failed to execute go build: exit status 1
C:\Users\Crockett\AppData\Local\Temp\go-fuzz-build377837498\goroot\src\time\zoneinfo_windows.go:9:2: cannot find package "internal/syscall/windows/registry" in any of:
        C:\Users\Crockett\AppData\Local\Temp\go-fuzz-build377837498\goroot\src\internal\syscall\windows\registry (from $GOROOT)
        C:\Users\Crockett\AppData\Local\Temp\go-fuzz-build377837498\gopath\src\internal\syscall\windows\registry (from $GOPATH)
C:\Users\Crockett\AppData\Local\Temp\go-fuzz-build377837498\goroot\src\syscall\dll_windows.go:8:2: cannot find package "internal/syscall/windows/sysdll" in any of:
        C:\Users\Crockett\AppData\Local\Temp\go-fuzz-build377837498\goroot\src\internal\syscall\windows\sysdll (from $GOROOT)
        C:\Users\Crockett\AppData\Local\Temp\go-fuzz-build377837498\gopath\src\internal\syscall\windows\sysdll (from $GOPATH)

However, when I add a dummy import of 'fmt' the error disappears and fuzzing works fine:

package fuzz

import "fmt"

var _ = fmt.Print

func Fuzz(buf []byte) int {
	switch len(buf) {
	case 5:
		panic("crash")
	case 7:
		return 1
	}
	return 0
}