diff --git a/source/lib/sysdep/sysdep.h b/source/lib/sysdep/sysdep.h
index 7748601d91..0233abdabd 100755
--- a/source/lib/sysdep/sysdep.h
+++ b/source/lib/sysdep/sysdep.h
@@ -17,10 +17,16 @@ extern "C" {
 
 extern void display_msg(const char* caption, const char* msg);
 extern void wdisplay_msg(const wchar_t* caption, const wchar_t* msg);
-extern void debug_out(const char* fmt, ...);
 
+extern void debug_out(const char* fmt, ...);
 extern void debug_break();
 
+
+// assert with stack trace (including variable / parameter types and values)
+// shown in a dialog, which offers
+//   continue, break, suppress (ignore this assert), and exit
+extern int debug_assert_failed(const char* file, int line, const char* expr);
+
 extern void check_heap();
 
 
diff --git a/source/lib/sysdep/win/wdbg.cpp b/source/lib/sysdep/win/wdbg.cpp
index 6b08bef155..6ad8edcabb 100755
--- a/source/lib/sysdep/win/wdbg.cpp
+++ b/source/lib/sysdep/win/wdbg.cpp
@@ -612,7 +612,7 @@ static void set_exception_handler()
 
 
 
-int wdbg_show_assert_dlg(char* file, int line, char* expr)
+int debug_assert_failed(const char* file, int line, const char* expr)
 {
 	ONCE(dbg_init());
 
diff --git a/source/lib/sysdep/win/wdbg.h b/source/lib/sysdep/win/wdbg.h
index b07744fa20..4de9b28a89 100755
--- a/source/lib/sysdep/win/wdbg.h
+++ b/source/lib/sysdep/win/wdbg.h
@@ -8,28 +8,8 @@ extern "C" {
 #endif
 
 
-// assert with stack trace (including variable / parameter types and values)
-// shown in a dialog, which offers
-//   continue, break, suppress (ignore this assert), and exit
 
-// recommended use: assert2(expr && "descriptive string")
-#define assert2(expr)\
-{\
-	static int suppress__;\
-	if(!suppress__ && !expr)\
-		switch(wdbg_show_assert_dlg(__FILE__, __LINE__, #expr))\
-		{\
-		case 1:\
-			suppress__ = 1;\
-			break;\
-\
-		case 2:\
-			win_debug_break();\
-			break;\
-		}\
-}
 
-extern int wdbg_show_assert_dlg(char* file, int line, char* expr);
 
 
 #ifdef __cplusplus