diff --git a/lib/source-map-consumer.js b/lib/source-map-consumer.js
index 17ef92b1..f5f96460 100644
--- a/lib/source-map-consumer.js
+++ b/lib/source-map-consumer.js
@@ -283,7 +283,7 @@ class BasicSourceMapConsumer extends SourceMapConsumer {
    * @returns BasicSourceMapConsumer
    */
   static fromSourceMap(aSourceMap, aSourceMapURL) {
-    return new BasicSourceMapConsumer(aSourceMap.toString());
+    return new BasicSourceMapConsumer(aSourceMap.toString(), aSourceMapURL);
   }
 
   get sources() {