C++ PATCH: PR 20145

[Mark Mitchell <mark at codesourcery dot com>]

This patch fixes PR c++/20145, a warning regression in 4.0.  When we
enter/exit template contexts we need to save/restore in_system_header.

Tested on x86_64-unknown-linux-gnu, applied on the mainline and the
4.0 branch.

--
Mark Mitchell
CodeSourcery, LLC
mark@codesourcery.com

2005-04-08  Mark Mitchell  <mark@codesourcery.com>

	* cp-tree.def (TINST_LEVEL): Document TINST_IN_SYSTEM_HEADER_P.
	* cp-tree.h (struct tinst_level): Add in_system_header_p.
	(TINST_IN_SYSTEM_HEADER_P): New macro.
	(make_tinst_level): Remove.
	* pt.c (lookup_template_class): Preserve DECL_IN_SYSTEM_HEADER on
	the instantiated class.
	(push_tinst_level): Do not use make_tinst_level.  Set
	TINST_IN_SYSTEM_HEADER_P.
	(pop_tinst_level): Likewise.
	(instantiate_class_template): Set in_system_header.
	(instantiate_pending_templates): Likewise.
	* tree.c (make_tinst_level): Remove.

2005-04-08  Mark Mitchell  <mark@codesourcery.com>

	PR c++/20145
	* g++.dg/warn/Wdtor1.C: New test.

Index: testsuite/g++.dg/warn/Wdtor1.C
===================================================================
RCS file: testsuite/g++.dg/warn/Wdtor1.C
diff -N testsuite/g++.dg/warn/Wdtor1.C
*** /dev/null	1 Jan 1970 00:00:00 -0000
--- testsuite/g++.dg/warn/Wdtor1.C	8 Apr 2005 19:30:49 -0000
***************
*** 0 ****
--- 1,18 ----
+ // PR c++/20145
+ // { dg-options "-Wnon-virtual-dtor" }
+ # 1 "t.cc"
+ # 1 "<built-in>"
+ # 1 "<command line>"
+ # 1 "t.cc"
+ # 1 "include/t.h" 1 3 4
+ template <int> class t
+ {
+   virtual void f();
+ };
+ # 2 "t.cc" 2
+ 
+ void f(void)
+ {
+   t<1> h;
+ }
+ 
Index: cp/cp-tree.def
===================================================================
RCS file: /cvs/gcc/gcc/gcc/cp/cp-tree.def,v
retrieving revision 1.95
diff -c -5 -p -r1.95 cp-tree.def
*** cp/cp-tree.def	6 Apr 2005 05:38:23 -0000	1.95
--- cp/cp-tree.def	8 Apr 2005 19:30:49 -0000
*************** DEFTREECODE (TAG_DEFN, "tag_defn", tcc_e
*** 287,296 ****
--- 287,297 ----
  
  /* Template instantiation level node.
  
     TINST_DECL contains the original DECL node.
     TINST_LOCATION contains the location where the template is instantiated.
+    TINST_IN_SYSTEM_HEADER_P is true if the location is in a system header.
  
     A stack of template instantiation nodes is kept through the TREE_CHAIN
     fields of these nodes.  */
  
  DEFTREECODE (TINST_LEVEL, "TINST_LEVEL", tcc_exceptional, 0)
Index: cp/cp-tree.h
===================================================================
RCS file: /cvs/gcc/gcc/gcc/cp/cp-tree.h,v
retrieving revision 1.1116
diff -c -5 -p -r1.1116 cp-tree.h
*** cp/cp-tree.h	1 Apr 2005 08:29:50 -0000	1.1116
--- cp/cp-tree.h	8 Apr 2005 19:30:50 -0000
*************** typedef struct template_parm_index_s tem
*** 219,228 ****
--- 219,229 ----
  struct tinst_level_s GTY(())
  {
    struct tree_common common;
    tree decl;
    location_t locus;
+   int in_system_header_p;
  };
  typedef struct tinst_level_s * tinst_level_t;
  
  struct ptrmem_cst GTY(())
  {
*************** typedef enum unification_kind_t {
*** 3119,3128 ****
--- 3120,3131 ----
  
  #define TINST_DECL(NODE) \
    (((tinst_level_t) TINST_LEVEL_CHECK (NODE))->decl)
  #define TINST_LOCATION(NODE) \
    (((tinst_level_t) TINST_LEVEL_CHECK (NODE))->locus)
+ #define TINST_IN_SYSTEM_HEADER_P(NODE) \
+   (((tinst_level_t) TINST_LEVEL_CHECK (NODE))->in_system_header_p)
  
  /* in class.c */
  
  extern int current_class_depth;
  
*************** extern tree no_linkage_check			(tree, bo
*** 4242,4252 ****
  extern void debug_binfo				(tree);
  extern tree build_dummy_object			(tree);
  extern tree maybe_dummy_object			(tree, tree *);
  extern int is_dummy_object			(tree);
  extern const struct attribute_spec cxx_attribute_table[];
- extern tree make_tinst_level                    (tree, location_t);
  extern tree make_ptrmem_cst                     (tree, tree);
  extern tree cp_build_type_attribute_variant     (tree, tree);
  extern tree cp_build_qualified_type_real        (tree, int, tsubst_flags_t);
  #define cp_build_qualified_type(TYPE, QUALS) \
    cp_build_qualified_type_real ((TYPE), (QUALS), tf_error | tf_warning)
--- 4245,4254 ----
Index: cp/pt.c
===================================================================
RCS file: /cvs/gcc/gcc/gcc/cp/pt.c,v
retrieving revision 1.991
diff -c -5 -p -r1.991 pt.c
*** cp/pt.c	6 Apr 2005 15:54:42 -0000	1.991
--- cp/pt.c	8 Apr 2005 19:30:50 -0000
*************** lookup_template_class (tree d1, 
*** 4607,4616 ****
--- 4607,4618 ----
  
        TREE_PRIVATE (type_decl)
  	= TREE_PRIVATE (TYPE_STUB_DECL (template_type));
        TREE_PROTECTED (type_decl)
  	= TREE_PROTECTED (TYPE_STUB_DECL (template_type));
+       DECL_IN_SYSTEM_HEADER (type_decl)
+ 	= DECL_IN_SYSTEM_HEADER (template);
  
        /* Set up the template information.  We have to figure out which
  	 template is the immediate parent if this is a full
  	 instantiation.  */
        if (parm_depth == 1 || is_partial_instantiation
*************** push_tinst_level (tree d)
*** 4999,5009 ****
        print_instantiation_context ();
  
        return 0;
      }
  
!   new = make_tinst_level (d, input_location);
    TREE_CHAIN (new) = current_tinst_level;
    current_tinst_level = new;
  
    ++tinst_depth;
  #ifdef GATHER_STATISTICS
--- 5001,5014 ----
        print_instantiation_context ();
  
        return 0;
      }
  
!   new = make_node (TINST_LEVEL);
!   TINST_DECL (new) = d;
!   TINST_LOCATION (new) = input_location;
!   TINST_IN_SYSTEM_HEADER_P (new) = in_system_header;
    TREE_CHAIN (new) = current_tinst_level;
    current_tinst_level = new;
  
    ++tinst_depth;
  #ifdef GATHER_STATISTICS
*************** pop_tinst_level (void)
*** 5024,5033 ****
--- 5029,5039 ----
    tree old = current_tinst_level;
  
    /* Restore the filename and line number stashed away when we started
       this instantiation.  */
    input_location = TINST_LOCATION (old);
+   in_system_header = TINST_IN_SYSTEM_HEADER_P (old);
    current_tinst_level = TREE_CHAIN (old);
    --tinst_depth;
    ++tinst_level_tick;
  }
  
*************** instantiate_class_template (tree type)
*** 5502,5512 ****
  
    SET_CLASSTYPE_INTERFACE_UNKNOWN (type);
  
    /* Set the input location to the template definition. This is needed
       if tsubsting causes an error.  */
!   input_location = DECL_SOURCE_LOCATION (TYPE_NAME (pattern));
  
    TYPE_HAS_CONSTRUCTOR (type) = TYPE_HAS_CONSTRUCTOR (pattern);
    TYPE_HAS_NEW_OPERATOR (type) = TYPE_HAS_NEW_OPERATOR (pattern);
    TYPE_HAS_ARRAY_NEW_OPERATOR (type) = TYPE_HAS_ARRAY_NEW_OPERATOR (pattern);
    TYPE_GETS_DELETE (type) = TYPE_GETS_DELETE (pattern);
--- 5508,5520 ----
  
    SET_CLASSTYPE_INTERFACE_UNKNOWN (type);
  
    /* Set the input location to the template definition. This is needed
       if tsubsting causes an error.  */
!   typedecl = TYPE_MAIN_DECL (type);
!   input_location = DECL_SOURCE_LOCATION (typedecl);
!   in_system_header = DECL_IN_SYSTEM_HEADER (typedecl);
  
    TYPE_HAS_CONSTRUCTOR (type) = TYPE_HAS_CONSTRUCTOR (pattern);
    TYPE_HAS_NEW_OPERATOR (type) = TYPE_HAS_NEW_OPERATOR (pattern);
    TYPE_HAS_ARRAY_NEW_OPERATOR (type) = TYPE_HAS_ARRAY_NEW_OPERATOR (pattern);
    TYPE_GETS_DELETE (type) = TYPE_GETS_DELETE (pattern);
*************** instantiate_class_template (tree type)
*** 5841,5851 ****
  
    /* Set the file and line number information to whatever is given for
       the class itself.  This puts error messages involving generated
       implicit functions at a predictable point, and the same point
       that would be used for non-template classes.  */
-   typedecl = TYPE_MAIN_DECL (type);
    input_location = DECL_SOURCE_LOCATION (typedecl);
  
    unreverse_member_declarations (type);
    finish_struct_1 (type);
    TYPE_BEING_DEFINED (type) = 0;
--- 5849,5858 ----
*************** instantiate_pending_templates (int retri
*** 11588,11597 ****
--- 11595,11605 ----
  {
    tree *t;
    tree last = NULL_TREE;
    int reconsider;
    location_t saved_loc = input_location;
+   int saved_in_system_header = in_system_header;
  
    /* Instantiating templates may trigger vtable generation.  This in turn
       may require further template instantiations.  We place a limit here
       to avoid infinite loop.  */
    if (pending_templates && retries >= max_tinst_depth)
*************** instantiate_pending_templates (int retri
*** 11672,11681 ****
--- 11680,11690 ----
        last_pending_template = last;
      } 
    while (reconsider);
  
    input_location = saved_loc;
+   in_system_header = saved_in_system_header;
  }
  
  /* Substitute ARGVEC into T, which is a list of initializers for
     either base class or a non-static data member.  The TREE_PURPOSEs
     are DECLs, and the TREE_VALUEs are the initializer values.  Used by
Index: cp/tree.c
===================================================================
RCS file: /cvs/gcc/gcc/gcc/cp/tree.c,v
retrieving revision 1.430
diff -c -5 -p -r1.430 tree.c
*** cp/tree.c	6 Apr 2005 04:57:38 -0000	1.430
--- cp/tree.c	8 Apr 2005 19:30:50 -0000
*************** handle_init_priority_attribute (tree* no
*** 1849,1869 ****
        *no_add_attrs = true;
        return NULL_TREE;
      }
  }
  
- /* Return a new TINST_LEVEL for DECL at location locus.  */
- tree
- make_tinst_level (tree decl, location_t locus)
- {
-   tree tinst_level = make_node (TINST_LEVEL);
-   TREE_CHAIN (tinst_level) = NULL_TREE;
-   TINST_DECL (tinst_level) = decl;
-   TINST_LOCATION (tinst_level) = locus;
-   return tinst_level;
- }
- 
  /* Return a new PTRMEM_CST of the indicated TYPE.  The MEMBER is the
     thing pointed to by the constant.  */
  
  tree
  make_ptrmem_cst (tree type, tree member)
--- 1849,1858 ----