diff --git a/C/stack.c b/C/stack.c
index f70df4097..d0176bb8d 100644
--- a/C/stack.c
+++ b/C/stack.c
@@ -1808,7 +1808,7 @@ void Yap_dump_stack(void) {
   yap_error_class_number classno = Yap_errorClass(errnb);
 
   fprintf(stderr, "%% Error STATUS: %s/%s\n\n", Yap_errorName(errnb),
-          Yap_errorName(classno));
+          Yap_errorClassName(classno));
 
   fprintf(stderr, "%% Execution mode\n");
   if (LOCAL_PrologMode & BootMode)
@@ -1846,7 +1846,7 @@ void Yap_dump_stack(void) {
   if (LOCAL_PrologMode & SystemMode)
     fprintf(stderr, "%%         Prolog Internals\n");
   if (LOCAL_PrologMode & AsyncIntMode)
-    fprintf(stderr, "%%         Async Interruot mode\n");
+    fprintf(stderr, "%%         Async Interrupt mode\n");
   if (LOCAL_PrologMode & InReadlineMode)
     fprintf(stderr, "%%         Readline Console\n");
   if (LOCAL_PrologMode & TopGoalMode)
@@ -1854,8 +1854,7 @@ void Yap_dump_stack(void) {
   fprintf(stderr, "%% \n%%  -------------------------------------\n%%\n");
   fprintf(stderr, "%% \n%%  YAP Program  :\n");
   fprintf(stderr, "%% \n%%  -------------------------------------\n%%\n");
-  fprintf(stderr, "%% Program Position\n\n", Yap_errorName(errno),
-          Yap_errorName(classno));
+  fprintf(stderr, "%% Program Position\n\n");
   Yap_detect_bug_location(CP, FIND_PRED_FROM_ANYWHERE, 256);
   fprintf(stderr, "%%          PC: %s\n", (char *)HR);
   Yap_detect_bug_location(CP, FIND_PRED_FROM_ANYWHERE, 256);
@@ -1928,7 +1927,7 @@ void Yap_dump_stack(void) {
       }
       if (b_ptr) {
         if (!max_count--) {
-          fprintf(stderr, "%%\**  .....\n");
+          fprintf(stderr, "%% \\**  .....\n");
           return;
         }
         if (b_ptr->cp_ap && /* tabling */
@@ -1947,6 +1946,7 @@ void Yap_dump_stack(void) {
   }
 }
 
+
 void DumpActiveGoals(USES_REGS1) {
   /* try to dump active goals */
   CELL *ep = YENV; /* and current environment		  */
@@ -2002,7 +2002,7 @@ void DumpActiveGoals(USES_REGS1) {
     op_numbers opnum;
     if (!ONLOCAL(b_ptr) || b_ptr->cp_b == NULL)
       break;
-    fprintf(stderr, "%%p ", b_ptr);
+    fprintf(stderr, "%% %p ", b_ptr);
     pe = Yap_PredForChoicePt(b_ptr, &opnum);
     if (opnum == _Nstop) {
       fprintf(stderr, "  ********** C-Code Interface Boundary ***********\n");
@@ -2090,15 +2090,15 @@ void Yap_detect_bug_location(yamop *yap_pc, int where_from, int psize) {
   if ((cl = Yap_PredForCode(yap_pc, where_from, &pred_name, &pred_arity,
                             &pred_module)) == 0) {
     /* system predicate */
-    fprintf(stderr, "%%s", "meta-call");
+    fprintf(stderr, "%% %s", "meta-call");
   } else if (pred_module == 0) {
     fprintf(stderr, "in prolog:%s/%lu", RepAtom(pred_name)->StrOfAE,
             (unsigned long int)pred_arity);
   } else if (cl < 0) {
-    fprintf(stderr, "%%s:%s/%lu", RepAtom(AtomOfTerm(pred_module))->StrOfAE,
+    fprintf(stderr, "%% %s:%s/%lu", RepAtom(AtomOfTerm(pred_module))->StrOfAE,
             RepAtom(pred_name)->StrOfAE, (unsigned long int)pred_arity);
   } else {
-    fprintf(stderr, "%%s:%s/%lu at clause %lu",
+    fprintf(stderr, "%% %s:%s/%lu at clause %lu",
             RepAtom(AtomOfTerm(pred_module))->StrOfAE,
             RepAtom(pred_name)->StrOfAE, (unsigned long int)pred_arity,
             (unsigned long int)cl);