2010-11-24 Richard Guenther <rguenther@suse.de>

	PR lto/46606
	* lto-streamer-in.c (input_gimple_stmt): When we cannot find
	a FIELD_DECL that is type correct issue a warning and fixup
	with a VIEW_CONVERT_EXPR.

git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@167115 138bc75d-0d04-0410-961f-82ee72b054a4

diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index cc0549c..bacb39c 100644 (file)
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,10 @@
+2010-11-24  Richard Guenther  <rguenther@suse.de>
+
+       PR lto/46606
+       * lto-streamer-in.c (input_gimple_stmt): When we cannot find
+       a FIELD_DECL that is type correct issue a warning and fixup
+       with a VIEW_CONVERT_EXPR.
+
 2010-11-24  Basile Starynkevitch  <basile@starynkevitch.net>
 
        * doc/invoke.texi (Options for Debugging Your Program or GCC):

diff --git a/gcc/lto-streamer-in.c b/gcc/lto-streamer-in.c
index cf1b011..4d36f06 100644 (file)
--- a/gcc/lto-streamer-in.c
+++ b/gcc/lto-streamer-in.c
@@ -956,25 +956,61 @@ input_gimple_stmt (struct lto_input_block *ib, struct data_in *data_in,
              if (TREE_CODE (op) == COMPONENT_REF)
                {
                  tree field, type, tem;
+                 tree closest_match = NULL_TREE;
                  field = TREE_OPERAND (op, 1);
                  type = DECL_CONTEXT (field);
                  for (tem = TYPE_FIELDS (type); tem; tem = TREE_CHAIN (tem))
                    {
-                     if (tem == field
-                         || (gimple_types_compatible_p (TREE_TYPE (tem),
-                                                        TREE_TYPE (field),
-                                                        GTC_DIAG)
-                             && DECL_NONADDRESSABLE_P (tem)
-                                == DECL_NONADDRESSABLE_P (field)
-                             && gimple_compare_field_offset (tem, field)))
+                     if (tem == field)
                        break;
+                     if (DECL_NONADDRESSABLE_P (tem)
+                         == DECL_NONADDRESSABLE_P (field)
+                         && gimple_compare_field_offset (tem, field))
+                       {
+                         if (gimple_types_compatible_p (TREE_TYPE (tem),
+                                                        TREE_TYPE (field),
+                                                        GTC_DIAG))
+                           break;
+                         else
+                           closest_match = tem;
+                       }
                    }
                  /* In case of type mismatches across units we can fail
                     to unify some types and thus not find a proper
-                    field-decl here.  So only assert here if checking
-                    is enabled.  */
-                 gcc_checking_assert (tem != NULL_TREE);
-                 if (tem != NULL_TREE)
+                    field-decl here.  */
+                 if (tem == NULL_TREE)
+                   {
+                     /* Thus, emit a ODR violation warning.  */
+                     if (warning_at (gimple_location (stmt), 0,
+                                     "use of type %<%E%> with two mismatching "
+                                     "declarations at field %<%E%>",
+                                     type, TREE_OPERAND (op, 1)))
+                       {
+                         if (TYPE_FIELDS (type))
+                           inform (DECL_SOURCE_LOCATION (TYPE_FIELDS (type)),
+                                   "original type declared here");
+                         inform (DECL_SOURCE_LOCATION (TREE_OPERAND (op, 1)),
+                                 "field in mismatching type declared here");
+                         if (TYPE_NAME (TREE_TYPE (field))
+                             && (TREE_CODE (TYPE_NAME (TREE_TYPE (field)))
+                                 == TYPE_DECL))
+                           inform (DECL_SOURCE_LOCATION
+                                     (TYPE_NAME (TREE_TYPE (field))),
+                                   "type of field declared here");
+                         if (closest_match
+                             && TYPE_NAME (TREE_TYPE (closest_match))
+                             && (TREE_CODE (TYPE_NAME
+                                  (TREE_TYPE (closest_match))) == TYPE_DECL))
+                           inform (DECL_SOURCE_LOCATION
+                                     (TYPE_NAME (TREE_TYPE (closest_match))),
+                                   "type of mismatching field declared here");
+                       }
+                     /* And finally fixup the types.  */
+                     TREE_OPERAND (op, 0)
+                       = build1 (VIEW_CONVERT_EXPR, type,
+                                 TREE_OPERAND (op, 0));
+                   }
+                 else
                    TREE_OPERAND (op, 1) = tem;
                }