diff --git a/include/ncurses_dll.h.in b/include/ncurses_dll.h.in
index 676850c..401d47a 100644
--- a/include/ncurses_dll.h.in
+++ b/include/ncurses_dll.h.in
@@ -1,5 +1,6 @@
 /****************************************************************************
- * Copyright (c) 1998-2009,2014 Free Software Foundation, Inc.              *
+ * Copyright 2018-2020,2023 Thomas E. Dickey                                *
+ * Copyright 2009,2014 Free Software Foundation, Inc.                       *
  *                                                                          *
  * Permission is hereby granted, free of charge, to any person obtaining a  *
  * copy of this software and associated documentation files (the            *
@@ -25,17 +26,30 @@
  * sale, use or other dealings in this Software without prior written       *
  * authorization.                                                           *
  ****************************************************************************/
-/* $Id: ncurses_dll.h.in,v 1.9 2014/08/02 21:30:20 tom Exp $ */
+/* $Id: ncurses_dll.h.in,v 1.18 2023/05/06 20:12:43 tom Exp $ */
 
 #ifndef NCURSES_DLL_H_incl
 #define NCURSES_DLL_H_incl 1
 
+/*
+ * MinGW gcc (unlike MSYS2 and Cygwin) should define _WIN32 and possibly _WIN64.
+ */
+#if defined(__MINGW64__)
+
+#ifndef _WIN64
+#define _WIN64 1
+#endif
+
+#elif defined(__MINGW32__)
+
+#ifndef _WIN32
+#define _WIN32 1
+#endif
+
 /* 2014-08-02 workaround for broken MinGW compiler.
  * Oddly, only TRACE is mapped to trace - the other -D's are okay.
  * suggest TDM as an alternative.
  */
-#if defined(__MINGW64__)
-#elif defined(__MINGW32__)
 #if (__GNUC__ == 4) && (__GNUC_MINOR__ == 8)
 
 #ifdef trace
@@ -44,6 +58,7 @@
 #endif
 
 #endif	/* broken compiler */
+
 #endif	/* MingW */
 
 /*
@@ -51,52 +66,38 @@
  * using functions to access them.
  */
 #define NCURSES_PUBLIC_VAR(name) @NCURSES_WRAP_PREFIX@##name
-#define NCURSES_WRAPPED_VAR(type,name) extern type NCURSES_PUBLIC_VAR(name)(void)
 
-/* no longer needed on cygwin or mingw, thanks to auto-import       */
-/* but this structure may be useful at some point for an MSVC build */
-/* so, for now unconditionally define the important flags           */
-/* "the right way" for proper static and dll+auto-import behavior   */
-#undef NCURSES_DLL
-#define NCURSES_STATIC
-
-#if defined(__CYGWIN__) || defined(__MINGW32__)
-#  if defined(NCURSES_DLL)
-#    if defined(NCURSES_STATIC)
-#      undef NCURSES_STATIC
-#    endif
-#  endif
-#  undef NCURSES_IMPEXP
-#  undef NCURSES_API
-#  undef NCURSES_EXPORT
-#  undef NCURSES_EXPORT_VAR
-#  if defined(NCURSES_DLL)
-/* building a DLL */
-#    define NCURSES_IMPEXP __declspec(dllexport)
-#  elif defined(NCURSES_STATIC)
-/* building or linking to a static library */
-#    define NCURSES_IMPEXP /* nothing */
-#  else
-/* linking to the DLL */
-#    define NCURSES_IMPEXP __declspec(dllimport)
-#  endif
-#  define NCURSES_API __cdecl
-#  define NCURSES_EXPORT(type) NCURSES_IMPEXP type NCURSES_API
-#  define NCURSES_EXPORT_VAR(type) NCURSES_IMPEXP type
+#if defined(BUILDING_NCURSES)
+# define NCURSES_IMPEXP NCURSES_EXPORT_GENERAL_EXPORT
+#else
+# define NCURSES_IMPEXP NCURSES_EXPORT_GENERAL_IMPORT
 #endif
 
-/* Take care of non-cygwin platforms */
-#if !defined(NCURSES_IMPEXP)
-#  define NCURSES_IMPEXP /* nothing */
-#endif
-#if !defined(NCURSES_API)
-#  define NCURSES_API /* nothing */
-#endif
-#if !defined(NCURSES_EXPORT)
-#  define NCURSES_EXPORT(type) NCURSES_IMPEXP type NCURSES_API
-#endif
-#if !defined(NCURSES_EXPORT_VAR)
-#  define NCURSES_EXPORT_VAR(type) NCURSES_IMPEXP type
+#define NCURSES_WRAPPED_VAR(type,name) extern NCURSES_IMPEXP type NCURSES_PUBLIC_VAR(name)(void)
+
+#define NCURSES_EXPORT(type) NCURSES_IMPEXP type NCURSES_API
+#define NCURSES_EXPORT_VAR(type) NCURSES_IMPEXP type
+
+/*
+ * These symbols hide dllimport/dllexport, for compilers which care about it.
+ */
+#if defined(__CYGWIN__) || (defined(_WIN32) || defined(_WIN64))
+# if defined(NCURSES_STATIC)	/* "static" here only implies "not-a-DLL" */
+#   define NCURSES_EXPORT_GENERAL_IMPORT
+#   define NCURSES_EXPORT_GENERAL_EXPORT
+# else
+#   define NCURSES_EXPORT_GENERAL_IMPORT __declspec(dllimport)
+#   define NCURSES_EXPORT_GENERAL_EXPORT __declspec(dllexport)
+# endif
+# define NCURSES_API __cdecl
+#else
+# define NCURSES_EXPORT_GENERAL_IMPORT
+# if (__GNUC__ >= 4) && !defined(__cplusplus)
+#   define NCURSES_EXPORT_GENERAL_EXPORT __attribute__((visibility ("default")))
+# else
+#   define NCURSES_EXPORT_GENERAL_EXPORT
+# endif
+# define NCURSES_API /* FIXME: __attribute__ ((cdecl)) is only available on x86 */
 #endif
 
 #endif /* NCURSES_DLL_H_incl */