diff --git a/string/public/nsAReadableString.h b/string/public/nsAReadableString.h
index f61f2a42c83..23223135ab6 100644
--- a/string/public/nsAReadableString.h
+++ b/string/public/nsAReadableString.h
@@ -1440,7 +1440,7 @@ basic_nsPromiseFlatString<CharT>::basic_nsPromiseFlatString( const basic_nsARead
     iterator end;
     
     aString.BeginReading(start);
-    aStrign.EndReading(end);
+    aString.EndReading(end);
 
     // First count the number of buffers
     PRInt32 buffer_count = 0;
diff --git a/xpcom/ds/nsAReadableString.h b/xpcom/ds/nsAReadableString.h
index f61f2a42c83..23223135ab6 100644
--- a/xpcom/ds/nsAReadableString.h
+++ b/xpcom/ds/nsAReadableString.h
@@ -1440,7 +1440,7 @@ basic_nsPromiseFlatString<CharT>::basic_nsPromiseFlatString( const basic_nsARead
     iterator end;
     
     aString.BeginReading(start);
-    aStrign.EndReading(end);
+    aString.EndReading(end);
 
     // First count the number of buffers
     PRInt32 buffer_count = 0;
diff --git a/xpcom/string/public/nsAReadableString.h b/xpcom/string/public/nsAReadableString.h
index f61f2a42c83..23223135ab6 100644
--- a/xpcom/string/public/nsAReadableString.h
+++ b/xpcom/string/public/nsAReadableString.h
@@ -1440,7 +1440,7 @@ basic_nsPromiseFlatString<CharT>::basic_nsPromiseFlatString( const basic_nsARead
     iterator end;
     
     aString.BeginReading(start);
-    aStrign.EndReading(end);
+    aString.EndReading(end);
 
     // First count the number of buffers
     PRInt32 buffer_count = 0;