diff --git a/src/in_memory_undo.c b/src/in_memory_undo.c
index 588f4b1c..313f54e9 100644
--- a/src/in_memory_undo.c
+++ b/src/in_memory_undo.c
@@ -203,8 +203,8 @@ static void mem_init_undo(void)
 {
   int slot;
 
-  dbg(1, "mem_init_undo(): undo_initialized = %d\n", xctx->undo_initialized);
-  if(!xctx->undo_initialized) {
+  dbg(1, "mem_init_undo(): undo_initialized = %d\n", xctx->mem_undo_initialized);
+  if(!xctx->mem_undo_initialized) {
     for(slot = 0;slot<MAX_UNDO; slot++) {
       xctx->uslot[slot].lines = my_calloc(_ALLOC_ID_, cadlayers, sizeof(int));
       xctx->uslot[slot].rects = my_calloc(_ALLOC_ID_, cadlayers, sizeof(int));
@@ -215,7 +215,7 @@ static void mem_init_undo(void)
       xctx->uslot[slot].aptr = my_calloc(_ALLOC_ID_, cadlayers, sizeof(xArc *));
       xctx->uslot[slot].pptr = my_calloc(_ALLOC_ID_, cadlayers, sizeof(xPoly *));
     }
-    xctx->undo_initialized = 1;
+    xctx->mem_undo_initialized = 1;
   }
 }
 
@@ -223,11 +223,11 @@ static void mem_init_undo(void)
 void mem_clear_undo(void)
 {
   int slot;
-  dbg(1, "mem_clear_undo(): undo_initialized = %d\n", xctx->undo_initialized);
+  dbg(1, "mem_clear_undo(): undo_initialized = %d\n", xctx->mem_undo_initialized);
   xctx->cur_undo_ptr = 0;
   xctx->tail_undo_ptr = 0;
   xctx->head_undo_ptr = 0;
-  if(!xctx->undo_initialized) return;
+  if(!xctx->mem_undo_initialized) return;
   for(slot = 0; slot<MAX_UNDO; slot++) {
     free_undo_lines(slot);
     free_undo_rects(slot);
@@ -244,8 +244,8 @@ void mem_clear_undo(void)
 void mem_delete_undo(void)
 {
   int slot;
-  dbg(1, "mem_delete_undo(): undo_initialized = %d\n", xctx->undo_initialized);
-  if(!xctx->undo_initialized) return;
+  dbg(1, "mem_delete_undo(): undo_initialized = %d\n", xctx->mem_undo_initialized);
+  if(!xctx->mem_undo_initialized) return;
   mem_clear_undo();
   for(slot = 0;slot<MAX_UNDO; slot++) {
     my_free(_ALLOC_ID_, &xctx->uslot[slot].lines);
@@ -257,7 +257,7 @@ void mem_delete_undo(void)
     my_free(_ALLOC_ID_, &xctx->uslot[slot].aptr);
     my_free(_ALLOC_ID_, &xctx->uslot[slot].pptr);
   }
-  xctx->undo_initialized = 0;
+  xctx->mem_undo_initialized = 0;
 }
 
 void mem_push_undo(void)
diff --git a/src/save.c b/src/save.c
index 40e7135d..3c7ede91 100644
--- a/src/save.c
+++ b/src/save.c
@@ -3570,7 +3570,7 @@ static void init_undo(void)
   if(xctx->no_undo == 0 && !xctx->undo_initialized) {
     /* create undo directory */
     if( !my_strdup(_ALLOC_ID_, &xctx->undo_dirname, create_tmpdir("xschem_undo_") )) {
-      dbg(0, "xinit(): problems creating tmp undo dir, Undo will be disabled\n");
+      dbg(0, "init_undo(): problems creating tmp undo dir, Undo will be disabled\n");
       dbg(0, "init_undo(): Check permissions in %s\n", tclgetvar("XSCHEM_TMP_DIR"));
       xctx->no_undo = 1; /* disable undo */
     }
diff --git a/src/xinit.c b/src/xinit.c
index 3a1586df..fafbf7c2 100644
--- a/src/xinit.c
+++ b/src/xinit.c
@@ -475,6 +475,7 @@ static void alloc_xschem_data(const char *top_path, const char *win_path)
     xctx->clear_undo = mem_clear_undo;
   }
   xctx->undo_initialized = 0;
+  xctx->mem_undo_initialized = 0;
   xctx->zoom=CADINITIALZOOM;
   xctx->mooz=1/CADINITIALZOOM;
   xctx->xorigin=CADINITIALX;
diff --git a/src/xschem.h b/src/xschem.h
index e8d39387..df46aeee 100644
--- a/src/xschem.h
+++ b/src/xschem.h
@@ -1082,6 +1082,7 @@ typedef struct {
   /* in_memory_undo */
   Undo_slot uslot[MAX_UNDO];
   int undo_initialized;
+  int mem_undo_initialized;
   /* graph context struct */
   Graph_ctx graph_struct;