-- go.mod --
module example.com/issue37756

go 1.14
-- a/a.go --
package a

import _ "example.com/issue37756/c"

func A1() {}
func A2() {}
-- b/b.go --
package b

func B1() {}
func B2() {}
-- c/c.go --
package c

func C1() {}
func C2() {}