[committed] PR debug/66535: guard check into parent's DIE
diff mbox

Message ID 557EFE96.3010309@redhat.com
State New
Headers show

Commit Message

Aldy Hernandez June 15, 2015, 4:34 p.m. UTC
The problem here is that the cached DIE does not have a parent because 
we purposely removed it, hoping that decls_for_scope will fill it in:

      /* If we're a nested function, initially use a parent of NULL; if 
we're
	 a plain function, this will be fixed up in decls_for_scope.  If
	 we're a method, it will be ignored, since we already have a DIE.  */

However, for the failing Ada testcase it _is_ decls_for_scope that we're 
being called from while we're doing the abstract instance dance while 
generating the containing type:

gen_typedef_die():
   ...
   origin = decl_ultimate_origin (decl);
   if (origin != NULL)
     add_abstract_origin_attribute (type_die, origin);

So...we haven't yet filled in the parent.  It doesn't really matter. 
We'll get it right, and besides, we shouldn't be dereferencing a 
parent's die field without checking the existence of said parent.

Long story short... committing as obvious.

Aldy
commit ee39c82907a029fe1403cf1d3a364b89e9dee998
Author: Aldy Hernandez <aldyh@redhat.com>
Date:   Mon Jun 15 09:19:45 2015 -0700

    	PR debug/66535
    	* dwarf2out.c (gen_subprogram_die): Do not check a parent's tag if
    	there is no parent.

Patch
diff mbox

diff --git a/gcc/dwarf2out.c b/gcc/dwarf2out.c
index d2c516a..4fe33f8 100644
--- a/gcc/dwarf2out.c
+++ b/gcc/dwarf2out.c
@@ -18790,7 +18790,8 @@  gen_subprogram_die (tree decl, dw_die_ref context_die)
 		   end function
 		 end module
 	   */
-	   || old_die->die_parent->die_tag == DW_TAG_module
+	   || (old_die->die_parent
+	       && old_die->die_parent->die_tag == DW_TAG_module)
 	   || context_die == NULL)
 	   && (DECL_ARTIFICIAL (decl)
 	       || (get_AT_file (old_die, DW_AT_decl_file) == file_index
diff --git a/gcc/testsuite/gnat.dg/debug4.adb b/gcc/testsuite/gnat.dg/debug4.adb
new file mode 100644
index 0000000..1ec37c2
--- /dev/null
+++ b/gcc/testsuite/gnat.dg/debug4.adb
@@ -0,0 +1,10 @@ 
+-- { dg-compile }
+-- { dg-options "-g" }
+
+with Debug4_Pkg;
+
+procedure Debug4 is
+   package P is new Debug4_Pkg (Natural);
+begin
+   null;
+end;
diff --git a/gcc/testsuite/gnat.dg/debug4_pkg.adb b/gcc/testsuite/gnat.dg/debug4_pkg.adb
new file mode 100644
index 0000000..18ba0c0
--- /dev/null
+++ b/gcc/testsuite/gnat.dg/debug4_pkg.adb
@@ -0,0 +1,23 @@ 
+package body Debug4_Pkg is
+
+   type Vertex_To_Vertex_T is array (Vertex_Id range <>) of Vertex_Id;
+
+   function Dominator_Tree_Internal (G : T'Class) return Vertex_To_Vertex_T is
+      subtype V_To_V is Vertex_To_Vertex_T (0 .. G.Vertices.Last_Index);
+      type V_To_VIL is array
+        (Valid_Vertex_Id range 1 .. G.Vertices.Last_Index)
+        of Vertex_Index_List;
+      Bucket : V_To_VIL := (others => VIL.Empty_Vector);
+      Dom    : V_To_V   := (others => 0);
+   begin
+      return Dom;
+   end;
+
+   function Dominator_Tree (G : T'Class) return T is
+      Dom : constant Vertex_To_Vertex_T := Dominator_Tree_Internal (G);
+      DT  : T := (Vertices => VL.Empty_Vector);
+   begin
+      return DT;
+   end;
+
+end Debug4_Pkg;
diff --git a/gcc/testsuite/gnat.dg/debug4_pkg.ads b/gcc/testsuite/gnat.dg/debug4_pkg.ads
new file mode 100644
index 0000000..bac4953
--- /dev/null
+++ b/gcc/testsuite/gnat.dg/debug4_pkg.ads
@@ -0,0 +1,28 @@ 
+with Ada.Containers.Vectors;
+
+generic
+   type Vertex_Key is private;
+package Debug4_Pkg is
+
+   type Vertex_Id is new Natural;
+   subtype Valid_Vertex_Id is Vertex_Id range 1 .. Vertex_Id'Last;
+
+   package VIL is new Ada.Containers.Vectors
+     (Index_Type   => Positive,
+      Element_Type => Valid_Vertex_Id);
+   use VIL;
+   subtype Vertex_Index_List is VIL.Vector;
+
+   package VL is new Ada.Containers.Vectors
+     (Index_Type   => Valid_Vertex_Id,
+      Element_Type => Vertex_Key);
+   use VL;
+   subtype Vertex_List is VL.Vector;
+
+   type T is tagged record
+      Vertices : Vertex_List;
+   end record;
+
+   function Dominator_Tree (G : T'Class) return T;
+
+end Debug4_Pkg;