diff --git a/js/js2/winbuild/js2.dsp b/js/js2/winbuild/js2.dsp
index 9bf094a2c561..cbd8cfee59e8 100644
--- a/js/js2/winbuild/js2.dsp
+++ b/js/js2/winbuild/js2.dsp
@@ -102,6 +102,10 @@ SOURCE=..\js2.cpp
 # End Source File
 # Begin Source File
 
+SOURCE=..\jstypes.cpp
+# End Source File
+# Begin Source File
+
 SOURCE=..\numerics.cpp
 # End Source File
 # Begin Source File
diff --git a/js2/src/winbuild/js2.dsp b/js2/src/winbuild/js2.dsp
index 9bf094a2c561..cbd8cfee59e8 100644
--- a/js2/src/winbuild/js2.dsp
+++ b/js2/src/winbuild/js2.dsp
@@ -102,6 +102,10 @@ SOURCE=..\js2.cpp
 # End Source File
 # Begin Source File
 
+SOURCE=..\jstypes.cpp
+# End Source File
+# Begin Source File
+
 SOURCE=..\numerics.cpp
 # End Source File
 # Begin Source File