diff --git a/C/sysbits.c b/C/sysbits.c
index 6c5287a8e..771346909 100644
--- a/C/sysbits.c
+++ b/C/sysbits.c
@@ -27,6 +27,9 @@ static char SccsId[] = "%W% %G%";
  *
  */
 
+#if  _MSC_VER || defined(__MINGW32__)
+#define _WIN32_WINNT 0x0400
+#endif
 #include "Yap.h"
 #include "yapio.h"
 #include "eval.h"
@@ -68,8 +71,7 @@ static char SccsId[] = "%W% %G%";
 #if HAVE_FCNTL_H
 #include <fcntl.h>
 #endif
-#ifdef _WIN32
-#define _WIN32_WINNT 0x0400
+#if  _MSC_VER || defined(__MINGW32__)
 #include <windows.h>
 /* required for DLL compatibility */
 #if HAVE_DIRECT_H
@@ -1976,8 +1978,7 @@ p_alarm(void)
       liDueTime.LowPart  = (DWORD) ( due_time & 0xFFFFFFFF );
       liDueTime.HighPart = (LONG)  ( due_time >> 32 );
       if (SetWaitableTimer(htimer, &liDueTime,0,HandleTimer,NULL,0) == 0) {
-	Error(SYSTEM_ERROR, TermNil,
-	      "alarm not available in this configuration");
+	WinError("trying to use alarm");
 	return(FALSE);
       }
     }
diff --git a/pl/debug.yap b/pl/debug.yap
index 0f06338be..ef5b6ed79 100644
--- a/pl/debug.yap
+++ b/pl/debug.yap
@@ -491,7 +491,7 @@ debugging :-
         CP is '$last_choice_pt',
 	(
 	    '$fetch_clause'(G,M,Cl,Clause),
-	    (Clause = true -> true ; '$call'(Clause,M,CP) )
+	    (Clause = true -> true ; '$call'(Clause,CP,Clause,M) )
 	;
 	     Next is Cl+1, '$set_value'(spy_cl,Next), fail
         ).
@@ -512,7 +512,7 @@ debugging :-
 	      '$fetch_reference_from_index'(Index, Cl1, Ref),
               instance(Ref, (G :- Clause))
             ),
-	    (Clause = true -> true ; '$call'(Clause,M,CP) )
+	    (Clause = true -> true ; '$call'(Clause,CP,Clause,M) )
 	;
 	     Next is Cl+1, '$set_value'(spy_cl,Next), fail
         ).
@@ -531,7 +531,7 @@ debugging :-
 	(
 	    '$db_nb_to_ref'(Cl,M:G,Ref),
 	    instance(Ref, (G :- Clause)),
-	    (Clause = true -> true ; '$call'(Clause,M,CP) )
+	    (Clause = true -> true ; '$call'(Clause,CP,Clause,M) )
 	;
 	    Next is Cl+1, '$set_value'(spy_cl,Next), fail
         ).
@@ -571,7 +571,7 @@ debugging :-
 	  ),
           (Clause = true -> true ;
 		% otherwise fast skip may try to interpret assembly builtins.
-             '$get_value'(spy_fs,1) -> '$call'(Clause,M,CP) ;
+             '$get_value'(spy_fs,1) -> '$call'(Clause,CP,Clause,M) ;
              '$creep_call'(Clause,M,CP)
             )
 	;
@@ -587,7 +587,7 @@ debugging :-
 	    instance(Ref, (G :- Clause)),
 	    (Clause = true -> true ;
 	     % otherwise fast skip may try to interpret assembly builtins.
-             '$get_value'(spy_fs,1) -> '$call'(Clause,M,CP) ;
+             '$get_value'(spy_fs,1) -> '$call'(Clause,CP,Clause,M) ;
              '$creep_call'(Clause,M,CP)
             )
 	;