diff --git a/src/cmd/go/internal/modload/buildlist.go b/src/cmd/go/internal/modload/buildlist.go
index 24b2585a55..3fbe3c6700 100644
--- a/src/cmd/go/internal/modload/buildlist.go
+++ b/src/cmd/go/internal/modload/buildlist.go
@@ -105,6 +105,7 @@ func newRequirements(depth modDepth, rootModules []module.Version, direct map[st
 	}
 
 	rs := &Requirements{
+		depth:          depth,
 		rootModules:    rootModules,
 		maxRootVersion: make(map[string]string, len(rootModules)),
 		direct:         direct,