diff -Naur make-4.2.1/main.c make-4.2.1.new/main.c
--- make-4.2.1/main.c	2016-05-31 09:17:26.000000000 +0200
+++ make-4.2.1.new/main.c	2017-02-20 22:55:09.051617838 +0100
@@ -1126,8 +1126,11 @@
 
 #endif
 
+/* setlocale interferes with line buffering if using parallel make on MinGW */
+#ifndef __MINGW32__
   /* Set up gettext/internationalization support.  */
   setlocale (LC_ALL, "");
+#endif
   /* The cast to void shuts up compiler warnings on systems that
      disable NLS.  */
   (void)bindtextdomain (PACKAGE, LOCALEDIR);