diff --git a/src/core/stdc/stdio.d b/src/core/stdc/stdio.d
index cf85ec2994..c0223b5c77 100644
--- a/src/core/stdc/stdio.d
+++ b/src/core/stdc/stdio.d
@@ -1721,7 +1721,15 @@ void perror(scope const char* s);
 
 version (CRuntime_DigitalMars)
 {
-    import core.sys.windows.windows;
+    version (none)
+        import core.sys.windows.windows : HANDLE, _WaitSemaphore, _ReleaseSemaphore;
+    else
+    {
+        // too slow to import windows
+        private alias void* HANDLE;
+        private void _WaitSemaphore(int iSemaphore);
+        private void _ReleaseSemaphore(int iSemaphore);
+    }
 
     enum
     {
@@ -1746,9 +1754,6 @@ version (CRuntime_DigitalMars)
     private extern __gshared HANDLE[_NFILE] _osfhnd;
     extern shared ubyte[_NFILE] __fhnd_info;
 
-    private void _WaitSemaphore(int iSemaphore);
-    private void _ReleaseSemaphore(int iSemaphore);
-
     // this is copied from semlock.h in DMC's runtime.
     private void LockSemaphore()(uint num)
     {