diff --git a/go/packages/golist.go b/go/packages/golist.go
index c6c08a6..4035086 100644
--- a/go/packages/golist.go
+++ b/go/packages/golist.go
@@ -7,7 +7,6 @@
 import (
 	"bytes"
 	"encoding/json"
-	"errors"
 	"fmt"
 	"go/types"
 	"io/ioutil"
@@ -739,16 +738,15 @@
 	}
 
 	if err := cmd.Run(); err != nil {
+		// Check for 'go' executable not being found.
+		if ee, ok := err.(*exec.Error); ok && ee.Err == exec.ErrNotFound {
+			return nil, fmt.Errorf("'go list' driver requires 'go', but %s", exec.ErrNotFound)
+		}
+
 		exitErr, ok := err.(*exec.ExitError)
 		if !ok {
 			// Catastrophic error:
-			// - executable not found
 			// - context cancellation
-
-			// Check for executable not existing.
-			if _, err := exec.LookPath("go"); err != nil {
-				return nil, errors.New("'go list' driver requires 'go' to be installed")
-			}
 			return nil, fmt.Errorf("couldn't exec 'go %v': %s %T", args, err, err)
 		}