[dispatch] Don't require debug_depth for untraced objects

src/hb-dispatch.hh

@@ -44,6 +44,7 @@ struct hb_dispatch_context_t
 	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>

src/hb-ot-layout-common.hh

@@ -160,15 +160,13 @@ struct hb_collect_variation_indices_context_t :
   hb_set_t *layout_variation_indices;
   const hb_set_t *glyph_set;
   const hb_map_t *gpos_lookups;
-  unsigned int debug_depth;
 
   hb_collect_variation_indices_context_t (hb_set_t *layout_variation_indices_,
 					  const hb_set_t *glyph_set_,
 					  const hb_map_t *gpos_lookups_) :
 					layout_variation_indices (layout_variation_indices_),
 					glyph_set (glyph_set_),
-					gpos_lookups (gpos_lookups_),
-					debug_depth (0) {}
+					gpos_lookups (gpos_lookups_) {}
 };
 
 template<typename OutputArray>

src/hb-ot-layout-gsubgpos.hh

@@ -50,11 +50,9 @@ struct hb_intersects_context_t :
   bool stop_sublookup_iteration (return_t r) const { return r; }
 
   const hb_set_t *glyphs;
-  unsigned int debug_depth;
 
   hb_intersects_context_t (const hb_set_t *glyphs_) :
-			     glyphs (glyphs_),
-			     debug_depth (0) {}
+			     glyphs (glyphs_) {}
 };
 
 struct hb_closure_context_t :
@@ -100,7 +98,6 @@ struct hb_closure_context_t :
   hb_set_t output[1];
   recurse_func_t recurse_func;
   unsigned int nesting_level_left;
-  unsigned int debug_depth;
 
   hb_closure_context_t (hb_face_t *face_,
 			hb_set_t *glyphs_,
@@ -110,7 +107,6 @@ struct hb_closure_context_t :
 			  glyphs (glyphs_),
 			  recurse_func (nullptr),
 			  nesting_level_left (nesting_level_left_),
-			  debug_depth (0),
 			  done_lookups (done_lookups_),
 			  lookup_count (0)
   {}
@@ -174,7 +170,6 @@ struct hb_closure_lookups_context_t :
   const hb_set_t *glyphs;
   recurse_func_t recurse_func;
   unsigned int nesting_level_left;
-  unsigned int debug_depth;
 
   hb_closure_lookups_context_t (hb_face_t *face_,
 				const hb_set_t *glyphs_,
@@ -185,7 +180,6 @@ struct hb_closure_lookups_context_t :
 				glyphs (glyphs_),
 				recurse_func (nullptr),
 				nesting_level_left (nesting_level_left_),
-				debug_depth (0),
 				visited_lookups (visited_lookups_),
 				inactive_lookups (inactive_lookups_),
 				lookup_count (0) {}
@@ -210,7 +204,6 @@ struct hb_would_apply_context_t :
   const hb_codepoint_t *glyphs;
   unsigned int len;
   bool zero_context;
-  unsigned int debug_depth;
 
   hb_would_apply_context_t (hb_face_t *face_,
 			    const hb_codepoint_t *glyphs_,
@@ -219,8 +212,7 @@ struct hb_would_apply_context_t :
 			      face (face_),
 			      glyphs (glyphs_),
 			      len (len_),
-			      zero_context (zero_context_),
-			      debug_depth (0) {}
+			      zero_context (zero_context_) {}
 };
 
 struct hb_collect_glyphs_context_t :
@@ -276,7 +268,6 @@ struct hb_collect_glyphs_context_t :
   recurse_func_t recurse_func;
   hb_set_t *recursed_lookups;
   unsigned int nesting_level_left;
-  unsigned int debug_depth;
 
   hb_collect_glyphs_context_t (hb_face_t *face_,
 			       hb_set_t  *glyphs_before, /* OUT.  May be NULL */
@@ -291,8 +282,7 @@ struct hb_collect_glyphs_context_t :
 			      output (glyphs_output ? glyphs_output : hb_set_get_empty ()),
 			      recurse_func (nullptr),
 			      recursed_lookups (hb_set_create ()),
-			      nesting_level_left (nesting_level_left_),
-			      debug_depth (0) {}
+			      nesting_level_left (nesting_level_left_) {}
   ~hb_collect_glyphs_context_t () { hb_set_destroy (recursed_lookups); }
 
   void set_recurse_func (recurse_func_t func) { recurse_func = func; }
@@ -315,11 +305,9 @@ struct hb_collect_coverage_context_t :
   }
 
   hb_collect_coverage_context_t (set_t *set_) :
-				   set (set_),
-				   debug_depth (0) {}
+				   set (set_) {}
 
   set_t *set;
-  unsigned int debug_depth;
 };
 
 

src/hb-ot-layout.cc

@@ -1977,11 +1977,9 @@ struct hb_get_glyph_alternates_dispatch_t :
   bool stop_sublookup_iteration (return_t r) const { return r; }
 
   hb_face_t *face;
-  unsigned int debug_depth;
 
   hb_get_glyph_alternates_dispatch_t (hb_face_t *face) :
-					face (face),
-					debug_depth (0) {}
+					face (face) {}
 
   private:
   template <typename T, typename ...Ts> auto