diff --git a/src/hb-aat-layout-common.hh b/src/hb-aat-layout-common.hh
index f186917fc..75d523f5f 100644
--- a/src/hb-aat-layout-common.hh
+++ b/src/hb-aat-layout-common.hh
@@ -820,7 +820,6 @@ struct hb_aat_apply_context_t :
 
   /* Unused. For debug tracing only. */
   unsigned int lookup_index;
-  unsigned int debug_depth;
 
   HB_INTERNAL hb_aat_apply_context_t (const hb_ot_shape_plan_t *plan_,
 				      hb_font_t *font_,
diff --git a/src/hb-aat-layout.cc b/src/hb-aat-layout.cc
index 49c908fd1..aa753cb86 100644
--- a/src/hb-aat-layout.cc
+++ b/src/hb-aat-layout.cc
@@ -56,8 +56,7 @@ AAT::hb_aat_apply_context_t::hb_aat_apply_context_t (const hb_ot_shape_plan_t *p
 						       buffer (buffer_),
 						       sanitizer (),
 						       ankr_table (&Null (AAT::ankr)),
-						       lookup_index (0),
-						       debug_depth (0)
+						       lookup_index (0)
 {
   sanitizer.init (blob);
   sanitizer.set_num_glyphs (face->get_num_glyphs ());
diff --git a/src/hb-dispatch.hh b/src/hb-dispatch.hh
index 327770a89..7eace86e5 100644
--- a/src/hb-dispatch.hh
+++ b/src/hb-dispatch.hh
@@ -38,13 +38,13 @@
 template <typename Context, typename Return=hb_empty_t, unsigned int MaxDebugDepth=0>
 struct hb_dispatch_context_t
 {
+  hb_dispatch_context_t () : debug_depth (0) {}
   private:
   /* https://en.wikipedia.org/wiki/Curiously_recurring_template_pattern */
   const Context* thiz () const { return static_cast<const Context *> (this); }
 	Context* thiz ()       { return static_cast<      Context *> (this); }
   public:
   const char *get_name () { return "UNKNOWN"; }
-  static constexpr unsigned debug_depth = 0;
   static constexpr unsigned max_debug_depth = MaxDebugDepth;
   typedef Return return_t;
   template <typename T, typename F>
@@ -54,6 +54,7 @@ struct hb_dispatch_context_t
   { return obj.dispatch (thiz (), hb_forward<Ts> (ds)...); }
   static return_t no_dispatch_return_value () { return Context::default_return_value (); }
   static bool stop_sublookup_iteration (const return_t r HB_UNUSED) { return false; }
+  unsigned debug_depth;
 };
 
 
diff --git a/src/hb-ot-layout-common.hh b/src/hb-ot-layout-common.hh
index 37f1d23bd..07b370691 100644
--- a/src/hb-ot-layout-common.hh
+++ b/src/hb-ot-layout-common.hh
@@ -126,7 +126,6 @@ struct hb_subset_layout_context_t :
   const hb_tag_t table_tag;
   const hb_map_t *lookup_index_map;
   const hb_map_t *feature_index_map;
-  unsigned debug_depth;
 
   hb_subset_layout_context_t (hb_subset_context_t *c_,
 			      hb_tag_t tag_,
@@ -136,7 +135,6 @@ struct hb_subset_layout_context_t :
 				table_tag (tag_),
 				lookup_index_map (lookup_map_),
 				feature_index_map (feature_map_),
-				debug_depth (0),
 				script_count (0),
 				langsys_count (0),
 				feature_index_count (0),
diff --git a/src/hb-ot-layout-gsubgpos.hh b/src/hb-ot-layout-gsubgpos.hh
index e935a9505..8b0e4323c 100644
--- a/src/hb-ot-layout-gsubgpos.hh
+++ b/src/hb-ot-layout-gsubgpos.hh
@@ -530,7 +530,6 @@ struct hb_ot_apply_context_t :
   unsigned int lookup_index;
   unsigned int lookup_props;
   unsigned int nesting_level_left;
-  unsigned int debug_depth;
 
   bool has_glyph_classes;
   bool auto_zwnj;
@@ -560,7 +559,6 @@ struct hb_ot_apply_context_t :
 			lookup_index ((unsigned int) -1),
 			lookup_props (0),
 			nesting_level_left (HB_MAX_NESTING_LEVEL),
-			debug_depth (0),
 			has_glyph_classes (gdef.has_glyph_classes ()),
 			auto_zwnj (true),
 			auto_zwj (true),
@@ -728,11 +726,9 @@ struct hb_get_subtables_context_t :
   static return_t default_return_value () { return hb_empty_t (); }
 
   hb_get_subtables_context_t (array_t &array_) :
-			      array (array_),
-			      debug_depth (0) {}
+			      array (array_) {}
 
   array_t &array;
-  unsigned int debug_depth;
 };
 
 
diff --git a/src/hb-sanitize.hh b/src/hb-sanitize.hh
index 091b3010f..024b4d1c9 100644
--- a/src/hb-sanitize.hh
+++ b/src/hb-sanitize.hh
@@ -121,7 +121,6 @@ struct hb_sanitize_context_t :
        hb_dispatch_context_t<hb_sanitize_context_t, bool, HB_DEBUG_SANITIZE>
 {
   hb_sanitize_context_t () :
-	debug_depth (0),
 	start (nullptr), end (nullptr),
 	max_ops (0), max_subtables (0),
 	writable (false), edit_count (0),
@@ -387,7 +386,6 @@ struct hb_sanitize_context_t :
     return sanitize_blob<Type> (hb_face_reference_table (face, tableTag));
   }
 
-  mutable unsigned int debug_depth;
   const char *start, *end;
   mutable int max_ops, max_subtables;
   private:
diff --git a/src/hb-subset.hh b/src/hb-subset.hh
index dc86f150c..c9b01c67f 100644
--- a/src/hb-subset.hh
+++ b/src/hb-subset.hh
@@ -58,7 +58,6 @@ struct hb_subset_context_t :
   hb_subset_plan_t *plan;
   hb_serialize_context_t *serializer;
   hb_tag_t table_tag;
-  unsigned int debug_depth;
 
   hb_subset_context_t (hb_blob_t *source_blob_,
 		       hb_subset_plan_t *plan_,
@@ -67,8 +66,7 @@ struct hb_subset_context_t :
 		        source_blob (source_blob_),
 			plan (plan_),
 			serializer (serializer_),
-			table_tag (table_tag_),
-			debug_depth (0) {}
+			table_tag (table_tag_) {}
 };