diff --git a/fec/build-dos.bat b/fec/build-dos.bat
index fbb7e5c..02425ec 100644
--- a/fec/build-dos.bat
+++ b/fec/build-dos.bat
@@ -26,10 +26,14 @@ wcl -q -za -wx -bt=dos -ml -k32768 -c -fo=parser.obj src\parser.c
 if errorlevel 1 goto build_fail
 wcl -q -za -wx -bt=dos -ml -k32768 -c -fo=types.obj src\types.c
 if errorlevel 1 goto build_fail
+wcl -q -za -wx -bt=dos -ml -k32768 -c -fo=m7.obj src\m7.c
+if errorlevel 1 goto build_fail
 wcl -q -za -wx -bt=dos -ml -k32768 -c -fo=own.obj src\own.c
 if errorlevel 1 goto build_fail
 wcl -q -za -wx -bt=dos -ml -k32768 -c -fo=check.obj src\check.c
 if errorlevel 1 goto build_fail
+wcl -q -za -wx -bt=dos -ml -k32768 -c -fo=lower.obj src\lower.c
+if errorlevel 1 goto build_fail
 rem Use an unambiguous short object name for the emit_c source.
 wcl -q -za -wx -bt=dos -ml -k32768 -c -fo=emitc.obj src\emit_c.c
 if errorlevel 1 goto build_fail