diff --git i/lib/clean-temp.c w/lib/clean-temp.c
index 40ec02f..1053312 100644
--- i/lib/clean-temp.c
+++ w/lib/clean-temp.c
@@ -582,6 +582,9 @@ static bool
 supports_delete_on_close ()
 {
   static int known; /* 1 = yes, -1 = no, 0 = unknown */
+  /* M4 wants to close and later reopen a temporary file, so
+     delete-on-close must not be used.  */
+  known = -1;
   if (!known)
     {
       OSVERSIONINFO v;