ada: Ignore ghost nodes in call graph information for dispatching calls

When emitting call graph information, we already skipped calls to
ignored ghost entities, but this code was causing crashes (in production
builds) and assertion failures (in development builds), because the
ignored ghost entities are not fully decorated, e.g. when they come from
instances of generic units with default subprograms.

With this patch we skip call graph information for ignored ghost
entities when they are registered, both as explicit calls and as
tagged types that will come with internally generated dispatching
subprograms.

gcc/ada/

	* exp_cg.adb (Generate_CG_Output): Remove code for ignored ghost
	entities that applied to subprogram calls.
	(Register_CG_Node): Skip ignored ghost entities, both calls
	and tagged types, when they are registered.

diff --git a/gcc/ada/exp_cg.adb b/gcc/ada/exp_cg.adb
index addf1cae32ac05650f540fd9d54843e984d78dce..91a6d40a6fa5a8115d6ce03bb198eda768a0781c 100644 (file)
--- a/gcc/ada/exp_cg.adb
+++ b/gcc/ada/exp_cg.adb
@@ -125,14 +125,7 @@ package body Exp_CG is
       for J in Call_Graph_Nodes.First .. Call_Graph_Nodes.Last loop
          N := Call_Graph_Nodes.Table (J);
 
-         --  No action needed for subprogram calls removed by the expander
-         --  (for example, calls to ignored ghost entities).
-
-         if Nkind (N) = N_Null_Statement then
-            pragma Assert (Nkind (Original_Node (N)) in N_Subprogram_Call);
-            null;
-
-         elsif Nkind (N) in N_Subprogram_Call then
+         if Nkind (N) in N_Subprogram_Call then
             Write_Call_Info (N);
 
          else pragma Assert (Nkind (N) = N_Defining_Identifier);
@@ -358,7 +351,13 @@ package body Exp_CG is
 
    procedure Register_CG_Node (N : Node_Id) is
    begin
-      if Nkind (N) in N_Subprogram_Call then
+      --  Skip ignored ghost calls that will be removed by the expander
+
+      if Is_Ignored_Ghost_Node (N) then
+         null;
+
+      elsif Nkind (N) in N_Subprogram_Call then
+
          if Current_Scope = Main_Unit_Entity
            or else Entity_Is_In_Main_Unit (Current_Scope)
          then