re PR c++/14329 ([4.1 only] badly formatted warnings for SRA replacements used uninitialized)

        PR tree-opt/14329
        * tree.h (struct tree_decl): Add debug_expr_is_from.
        (DECL_DEBUG_EXPR_IS_FROM): New.
        (DECL_DEBUG_EXPR): Rename from DECL_DEBUG_ALIAS_OF.
        * dwarf2out.c (dwarf2out_var_location): Update to match.
        * tree-outof-ssa.c (create_temp): Likewise.
        * var-tracking.c (track_expr_p): Likewise.
        * tree-sra.c (instantiate_element): Set DECL_DEBUG_EXPR.
        * c-objc-common.c (c_tree_printer) <'D'>: Handle DECL_DEBUG_EXPR.
        * toplev.c (default_tree_printer): Likewise.

From-SVN: r94317

9 files changed, 98 insertions, 22 deletions

diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index e7cfcd2..6999c43 100644
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,16 @@
+2005-01-27  Richard Henderson  <rth@redhat.com>
+
+	PR tree-opt/14329
+	* tree.h (struct tree_decl): Add debug_expr_is_from.
+	(DECL_DEBUG_EXPR_IS_FROM): New.
+	(DECL_DEBUG_EXPR): Rename from DECL_DEBUG_ALIAS_OF.
+	* dwarf2out.c (dwarf2out_var_location): Update to match.
+	* tree-outof-ssa.c (create_temp): Likewise.
+	* var-tracking.c (track_expr_p): Likewise.
+	* tree-sra.c (instantiate_element): Set DECL_DEBUG_EXPR.
+	* c-objc-common.c (c_tree_printer) <'D'>: Handle DECL_DEBUG_EXPR.
+	* toplev.c (default_tree_printer): Likewise.
+
 2005-01-27  Alexandre Oliva  <aoliva@redhat.com>
 
 	* config/frv/frv.c (frv_class_likely_spilled_p): Add GR8_REGS,
diff --git a/gcc/c-objc-common.c b/gcc/c-objc-common.c
index 35bcf9e..50bb0fc 100644
--- a/gcc/c-objc-common.c
+++ b/gcc/c-objc-common.c
@@ -177,6 +177,17 @@ c_tree_printer (pretty_printer *pp, text_info *text)
   switch (*text->format_spec)
     {
     case 'D':
+      if (DECL_DEBUG_EXPR (t) && DECL_DEBUG_EXPR_IS_FROM (t))
+	{
+	  t = DECL_DEBUG_EXPR (t);
+	  if (!DECL_P (t))
+	    {
+	      pp_c_expression (cpp, t);
+	      return true;
+	    }
+	}
+      /* FALLTHRU */
+
     case 'F':
       if (DECL_NAME (t))
 	n = lang_hooks.decl_printable_name (t, 2);
diff --git a/gcc/dwarf2out.c b/gcc/dwarf2out.c
index 6336cf6..49bca54 100644
--- a/gcc/dwarf2out.c
+++ b/gcc/dwarf2out.c
@@ -13131,8 +13131,9 @@ dwarf2out_var_location (rtx loc_note)
   last_insn = loc_note;
   last_label = newloc->label;
   decl = NOTE_VAR_LOCATION_DECL (loc_note);
-  if (DECL_DEBUG_ALIAS_OF (decl))
-    decl = DECL_DEBUG_ALIAS_OF (decl); 
+  if (DECL_DEBUG_EXPR (decl) && DECL_DEBUG_EXPR_IS_FROM (decl)
+      && DECL_P (DECL_DEBUG_EXPR (decl)))
+    decl = DECL_DEBUG_EXPR (decl); 
   add_var_loc_to_decl (decl, newloc);
 }
 
diff --git a/gcc/testsuite/gcc.dg/uninit-I.c b/gcc/testsuite/gcc.dg/uninit-I.c
new file mode 100644
index 0000000..bd7c13a
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/uninit-I.c
@@ -0,0 +1,8 @@
+/* { dg-do compile } */
+/* { dg-options -O2 -Wuninitialized } */
+
+int sys_msgctl (void)
+{
+  struct { int mode; } setbuf;  /* { dg-warning "'setbuf[.]mode' is used" } */
+  return setbuf.mode;
+}
diff --git a/gcc/toplev.c b/gcc/toplev.c
index af57e57..2659997 100644
--- a/gcc/toplev.c
+++ b/gcc/toplev.c
@@ -1554,23 +1554,36 @@ default_pch_valid_p (const void *data_p, size_t len)
 static bool
 default_tree_printer (pretty_printer * pp, text_info *text)
 {
+  tree t;
+
   switch (*text->format_spec)
     {
     case 'D':
+      t = va_arg (*text->args_ptr, tree);
+      if (DECL_DEBUG_EXPR (t) && DECL_DEBUG_EXPR_IS_FROM (t))
+	t = DECL_DEBUG_EXPR (t);
+      break;
+
     case 'F':
     case 'T':
-      {
-        tree t = va_arg (*text->args_ptr, tree);
-        const char *n = DECL_NAME (t)
-          ? lang_hooks.decl_printable_name (t, 2)
-          : "<anonymous>";
-        pp_string (pp, n);
-      }
-      return true;
+      t = va_arg (*text->args_ptr, tree);
+      break;
 
     default:
       return false;
     }
+
+  if (DECL_P (t))
+    {
+      const char *n = DECL_NAME (t)
+        ? lang_hooks.decl_printable_name (t, 2)
+        : "<anonymous>";
+      pp_string (pp, n);
+    }
+  else
+    dump_generic_node (pp, t, 0, 0, 0);
+
+  return true;
 }
 
 /* Initialization of the front end environment, before command line
diff --git a/gcc/tree-outof-ssa.c b/gcc/tree-outof-ssa.c
index 430e8ca..65c74d3 100644
--- a/gcc/tree-outof-ssa.c
+++ b/gcc/tree-outof-ssa.c
@@ -157,10 +157,16 @@ create_temp (tree t)
     name = "temp";
   tmp = create_tmp_var (type, name);
 
-  if (DECL_DEBUG_ALIAS_OF (t))
-    DECL_DEBUG_ALIAS_OF (tmp) = DECL_DEBUG_ALIAS_OF (t);  
+  if (DECL_DEBUG_EXPR (t) && DECL_DEBUG_EXPR_IS_FROM (t))
+    {
+      DECL_DEBUG_EXPR (tmp) = DECL_DEBUG_EXPR (t);  
+      DECL_DEBUG_EXPR_IS_FROM (tmp) = 1;
+    }
   else if (!DECL_IGNORED_P (t))
-    DECL_DEBUG_ALIAS_OF (tmp) = t;
+    {
+      DECL_DEBUG_EXPR (tmp) = t;
+      DECL_DEBUG_EXPR_IS_FROM (tmp) = 1;
+    }
   DECL_ARTIFICIAL (tmp) = DECL_ARTIFICIAL (t);
   DECL_IGNORED_P (tmp) = DECL_IGNORED_P (t);
   add_referenced_tmp_var (tmp);
diff --git a/gcc/tree-sra.c b/gcc/tree-sra.c
index 1ac0ec0..01bf53c 100644
--- a/gcc/tree-sra.c
+++ b/gcc/tree-sra.c
@@ -144,6 +144,8 @@ static struct obstack sra_obstack;
 static void dump_sra_elt_name (FILE *, struct sra_elt *);
 extern void debug_sra_elt_name (struct sra_elt *);
 
+/* Forward declarations.  */
+static tree generate_element_ref (struct sra_elt *);
 
 /* Return true if DECL is an SRA candidate.  */
 
@@ -1112,15 +1114,25 @@ instantiate_element (struct sra_elt *elt)
 
   elt->replacement = var = make_rename_temp (elt->type, "SR");
   DECL_SOURCE_LOCATION (var) = DECL_SOURCE_LOCATION (base);
-  TREE_NO_WARNING (var) = TREE_NO_WARNING (base);
-  DECL_ARTIFICIAL (var) = DECL_ARTIFICIAL (base);
-  DECL_IGNORED_P (var) = DECL_IGNORED_P (base);
+  DECL_ARTIFICIAL (var) = 1;
 
   if (DECL_NAME (base) && !DECL_IGNORED_P (base))
     {
       char *pretty_name = build_element_name (elt);
       DECL_NAME (var) = get_identifier (pretty_name);
       obstack_free (&sra_obstack, pretty_name);
+
+      DECL_DEBUG_EXPR (var) = generate_element_ref (elt);
+      DECL_DEBUG_EXPR_IS_FROM (var) = 1;
+
+      DECL_IGNORED_P (var) = 0;
+      TREE_NO_WARNING (var) = TREE_NO_WARNING (base);
+    }
+  else
+    {
+      DECL_IGNORED_P (var) = 1;
+      /* ??? We can't generate any warning that would be meaningful.  */
+      TREE_NO_WARNING (var) = 1;
     }
 
   if (dump_file)
diff --git a/gcc/tree.h b/gcc/tree.h
index b393cab..a4c590b 100644
--- a/gcc/tree.h
+++ b/gcc/tree.h
@@ -2018,9 +2018,13 @@ struct tree_binfo GTY (())
    writing debugging information about vfield and vbase decls for C++.  */
 #define DECL_FCONTEXT(NODE) (FIELD_DECL_CHECK (NODE)->decl.vindex)
 
-/* For VAR_DECL, this is set to the variable we were split from, due to
-   optimization. */
-#define DECL_DEBUG_ALIAS_OF(NODE) (DECL_CHECK (NODE)->decl.vindex)
+/* For VAR_DECL, this is set to either an expression that it was split
+   from (if DECL_DEBUG_EXPR_IS_FROM is true), otherwise a tree_list of
+   subexpressions that it was split into.  */
+#define DECL_DEBUG_EXPR(NODE) (DECL_CHECK (NODE)->decl.vindex)
+
+#define DECL_DEBUG_EXPR_IS_FROM(NODE) \
+  (DECL_CHECK (NODE)->decl.debug_expr_is_from)
 
 /* Every ..._DECL node gets a unique number.  */
 #define DECL_UID(NODE) (DECL_CHECK (NODE)->decl.uid)
@@ -2361,7 +2365,8 @@ struct tree_decl GTY(())
   unsigned possibly_inlined : 1;
   unsigned preserve_flag: 1;
   unsigned gimple_formal_temp : 1;
-  /* 13 unused bits.  */
+  unsigned debug_expr_is_from : 1;
+  /* 12 unused bits.  */
 
   union tree_decl_u1 {
     /* In a FUNCTION_DECL for which DECL_BUILT_IN holds, this is
diff --git a/gcc/var-tracking.c b/gcc/var-tracking.c
index 14a1dc2..7621313 100644
--- a/gcc/var-tracking.c
+++ b/gcc/var-tracking.c
@@ -1460,8 +1460,15 @@ track_expr_p (tree expr)
      don't need to track this expression if the ultimate declaration is
      ignored.  */
   realdecl = expr;
-  if (DECL_DEBUG_ALIAS_OF (realdecl))
-    realdecl = DECL_DEBUG_ALIAS_OF  (realdecl);
+  if (DECL_DEBUG_EXPR (realdecl)
+      && DECL_DEBUG_EXPR_IS_FROM (realdecl))
+    {
+      realdecl = DECL_DEBUG_EXPR (realdecl);
+      /* ??? We don't yet know how to emit DW_OP_piece for variable
+	 that has been SRA'ed.  */
+      if (!DECL_P (realdecl))
+	return 0;
+    }
 
   /* Do not track EXPR if REALDECL it should be ignored for debugging
      purposes.  */