diff --git a/src/rt/monitor_.d b/src/rt/monitor_.d
index f73e32137b..be0672e255 100644
--- a/src/rt/monitor_.d
+++ b/src/rt/monitor_.d
@@ -155,11 +155,6 @@ version (Windows)
     {
         pragma(lib, "snn.lib");
     }
-    else version (CRuntime_Microsoft)
-    {
-        pragma(lib, "libcmt.lib");
-        pragma(lib, "oldnames.lib");
-    }
     import core.sys.windows.windows;
 
     alias Mutex = CRITICAL_SECTION;
diff --git a/win64.mak b/win64.mak
index fea4d5d475..89f28a4941 100644
--- a/win64.mak
+++ b/win64.mak
@@ -28,6 +28,9 @@ DRUNTIME_BASE=druntime$(MODEL)
 DRUNTIME=lib\$(DRUNTIME_BASE).lib
 GCSTUB=lib\gcstub$(MODEL).obj
 
+# do not preselect a C runtime (extracted from the line above to make the auto tester happy)
+CFLAGS=$(CFLAGS) /Zl
+
 DOCFMT=
 
 target : import copydir copy $(DRUNTIME) $(GCSTUB)