diff --git a/m4/np-compat.m4 b/m4/np-compat.m4
index c4e7f8d4..e1a459d2 100644
--- a/m4/np-compat.m4
+++ b/m4/np-compat.m4
@@ -2,14 +2,19 @@ AC_DEFUN([AC_FLDIGI_NP_COMPAT], [
   AC_REQUIRE([AC_FLDIGI_MACOSX])
   AC_REQUIRE([AC_FLDIGI_WIN32])
 
-  AM_CONDITIONAL([COMPAT_REGEX], [test "x$ac_cv_header_regex_h" != "xyes"])
 
   if test "x$target_mingw32" = "xyes"; then
       # Newer versions of mingw32 comes with pthread.
       sem_libs="pthreadGC2 pthread"
+     # pretend that the regex.h check failed so that we use the bundled regex code
+     ac_cv_header_regex_h=no
+     AC_DEFINE([HAVE_REGEX_H], 0, [Define to 1 if you have the <regex.h> header file.])
   else
       sem_libs="pthread rt"
   fi
+  AM_CONDITIONAL([COMPAT_REGEX], [test "x$ac_cv_header_regex_h" != "xyes"])
+
+
   other_libs=""
 
   if test "x$ac_cv_want_ptw32" = "xyes"; then