--- src/autofit/afcjk.c
+++ src/autofit/afcjk.c
@@ -843,7 +843,7 @@
   {
     AF_AxisHints  axis          = &hints->axis[dim];
     AF_Segment    segments      = axis->segments;
-    AF_Segment    segment_limit = segments + axis->num_segments;
+    AF_Segment    segment_limit = axis->num_segments == 0 ? segments : segments + axis->num_segments;
     AF_Direction  major_dir     = axis->major_dir;
     AF_Segment    seg1, seg2;
     FT_Pos        len_threshold;
@@ -1005,7 +1005,7 @@
     AF_CJKAxis    laxis  = &((AF_CJKMetrics)hints->metrics)->axis[dim];
 
     AF_Segment    segments      = axis->segments;
-    AF_Segment    segment_limit = segments + axis->num_segments;
+    AF_Segment    segment_limit = axis->num_segments == 0 ? segments : segments + axis->num_segments;
     AF_Segment    seg;
 
     FT_Fixed      scale;
@@ -1153,7 +1153,7 @@
      */
     {
       AF_Edge  edges      = axis->edges;
-      AF_Edge  edge_limit = edges + axis->num_edges;
+      AF_Edge  edge_limit = axis->num_edges == 0 ? edges : edges + axis->num_edges;
       AF_Edge  edge;
 
 
@@ -1291,7 +1291,7 @@
   {
     AF_AxisHints  axis       = &hints->axis[dim];
     AF_Edge       edge       = axis->edges;
-    AF_Edge       edge_limit = edge + axis->num_edges;
+    AF_Edge       edge_limit = axis->num_edges == 0 ? edge : edge + axis->num_edges;
     AF_CJKAxis    cjk        = &metrics->axis[dim];
     FT_Fixed      scale      = cjk->scale;
     FT_Pos        best_dist0;  /* initial threshold */
@@ -1798,7 +1798,7 @@
   {
     AF_AxisHints  axis       = &hints->axis[dim];
     AF_Edge       edges      = axis->edges;
-    AF_Edge       edge_limit = edges + axis->num_edges;
+    AF_Edge       edge_limit = axis->num_edges == 0 ? edges : edges + axis->num_edges;
     FT_PtrDist    n_edges;
     AF_Edge       edge;
     AF_Edge       anchor   = NULL;
@@ -2177,7 +2177,7 @@
   {
     AF_AxisHints  axis       = & hints->axis[dim];
     AF_Edge       edges      = axis->edges;
-    AF_Edge       edge_limit = edges + axis->num_edges;
+    AF_Edge       edge_limit = axis->num_edges == 0 ? edges : edges + axis->num_edges;
     AF_Edge       edge;
     FT_Bool       snapping;
 
--- src/autofit/afhints.c
+++ src/autofit/afhints.c
@@ -1316,7 +1316,7 @@
   {
     AF_AxisHints  axis          = & hints->axis[dim];
     AF_Segment    segments      = axis->segments;
-    AF_Segment    segment_limit = segments + axis->num_segments;
+    AF_Segment    segment_limit = axis->num_segments == 0 ? segments : segments + axis->num_segments;
     AF_Segment    seg;
 
 
@@ -1393,7 +1393,7 @@
     AF_Point      point_limit = points + hints->num_points;
     AF_AxisHints  axis        = &hints->axis[dim];
     AF_Edge       edges       = axis->edges;
-    AF_Edge       edge_limit  = edges + axis->num_edges;
+    AF_Edge       edge_limit  = axis->num_edges == 0 ? edges : edges + axis->num_edges;
     FT_UInt       touch_flag;
 
 
--- src/autofit/aflatin.c
+++ src/autofit/aflatin.c
@@ -1989,7 +1989,7 @@
   {
     AF_AxisHints  axis          = &hints->axis[dim];
     AF_Segment    segments      = axis->segments;
-    AF_Segment    segment_limit = segments + axis->num_segments;
+    AF_Segment    segment_limit = axis->num_segments == 0 ? segments : segments + axis->num_segments;
     FT_Pos        len_threshold, len_score, dist_score, max_width;
     AF_Segment    seg1, seg2;
 
@@ -2134,7 +2134,7 @@
     FT_Bool  top_to_bottom_hinting = 0;
 
     AF_Segment    segments      = axis->segments;
-    AF_Segment    segment_limit = segments + axis->num_segments;
+    AF_Segment    segment_limit = axis->num_segments == 0 ? segments : segments + axis->num_segments;
     AF_Segment    seg;
 
 #if 0
@@ -2500,7 +2500,7 @@
   {
     AF_AxisHints  axis       = &hints->axis[AF_DIMENSION_VERT];
     AF_Edge       edge       = axis->edges;
-    AF_Edge       edge_limit = edge + axis->num_edges;
+    AF_Edge       edge_limit = axis->num_edges == 0 ? edge : edge + axis->num_edges;
     AF_LatinAxis  latin      = &metrics->axis[AF_DIMENSION_VERT];
     FT_Fixed      scale      = latin->scale;
 
@@ -2993,7 +2993,7 @@
   {
     AF_AxisHints  axis       = &hints->axis[dim];
     AF_Edge       edges      = axis->edges;
-    AF_Edge       edge_limit = edges + axis->num_edges;
+    AF_Edge       edge_limit = axis->num_edges == 0 ? edges : edges + axis->num_edges;
     FT_PtrDist    n_edges;
     AF_Edge       edge;
     AF_Edge       anchor     = NULL;
--- src/truetype/ttgxvar.c
+++ src/truetype/ttgxvar.c
@@ -964,7 +964,7 @@
     /* in the OpenType specification.                  */
 
     varData  = &itemStore->varData[outerIndex];
-    deltaSet = &varData->deltaSet[varData->regionIdxCount * innerIndex];
+    deltaSet = varData->regionIdxCount * innerIndex == 0 ? varData->deltaSet : &varData->deltaSet[varData->regionIdxCount * innerIndex];
 
     /* outer loop steps through master designs to be blended */
     for ( master = 0; master < varData->regionIdxCount; master++ )