From 311fa510e6d737db7727ab6f4bd1c5598f2b217c Mon Sep 17 00:00:00 2001
From: Le-Chun Wu <lcwu@gcc.gnu.org>
Date: Mon, 20 Apr 2009 21:13:08 +0000
Subject: [PATCH] re PR c++/39803 (Bogus 'unused value' warning on declarations
 of non-POD arrays)

        PR c++/39803
	* gcc/cp/init.c (build_vec_init): Set TREE_NO_WARNING on the
	compiler-generated INDIRECT_REF expression.
	* gcc/testsuite/g++.dg/warn/Wunused-14.C: New test.

From-SVN: r146454
---
 gcc/cp/ChangeLog                       |  8 +++++++-
 gcc/cp/init.c                          |  1 +
 gcc/testsuite/ChangeLog                |  5 +++++
 gcc/testsuite/g++.dg/warn/Wunused-14.C | 14 ++++++++++++++
 4 files changed, 27 insertions(+), 1 deletion(-)
 create mode 100644 gcc/testsuite/g++.dg/warn/Wunused-14.C

diff --git a/gcc/cp/ChangeLog b/gcc/cp/ChangeLog
index 0d014f57a17..15f83d9fb88 100644
--- a/gcc/cp/ChangeLog
+++ b/gcc/cp/ChangeLog
@@ -1,3 +1,9 @@
+2009-04-20  Le-Chun Wu  <lcwu@google.com>
+
+	PR c++/39803
+	* init.c (build_vec_init): Set TREE_NO_WARNING on the
+	compiler-generated INDIRECT_REF expression.
+
 2009-04-20  Ian Lance Taylor  <iant@google.com>
 
 	* typeck.c (build_function_call_vec): New function.
@@ -34,7 +40,7 @@
 	* cp-tree.h (enum tsubst_flags): Rename from enum tsubst_flags_t.
 	(tsubst_flags_t): Change typedef from enum type to int.
 
-2009-04-16  Le-Chun Wu  <lcwu@google.com>
+2009-04-16  Paolo Bonzini  <bonzini@gnu.org>
 
 	* decl.c (check_initializer): Use TYPE_VECTOR_OPAQUE
 	instead of targetm.vector_opaque_p.
diff --git a/gcc/cp/init.c b/gcc/cp/init.c
index 812042d7f7f..d40a5e7e53f 100644
--- a/gcc/cp/init.c
+++ b/gcc/cp/init.c
@@ -2920,6 +2920,7 @@ build_vec_init (tree base, tree maxindex, tree init,
       atype = build_pointer_type (atype);
       stmt_expr = build1 (NOP_EXPR, atype, stmt_expr);
       stmt_expr = cp_build_indirect_ref (stmt_expr, NULL, complain);
+      TREE_NO_WARNING (stmt_expr) = 1;
     }
 
   current_stmt_tree ()->stmts_are_full_exprs_p = destroy_temps;
diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog
index 478e8936812..c58967338c1 100644
--- a/gcc/testsuite/ChangeLog
+++ b/gcc/testsuite/ChangeLog
@@ -1,3 +1,8 @@
+2009-04-20  Le-Chun Wu  <lcwu@google.com>
+
+	PR c++/39803
+	* g++.dg/warn/Wunused-14.C: New test.
+
 2009-04-20  Eric Botcazou  <ebotcazou@adacore.com>
 
 	* gnat.dg/specs/small_alignment.ads: New test.
diff --git a/gcc/testsuite/g++.dg/warn/Wunused-14.C b/gcc/testsuite/g++.dg/warn/Wunused-14.C
new file mode 100644
index 00000000000..b325ccb71dd
--- /dev/null
+++ b/gcc/testsuite/g++.dg/warn/Wunused-14.C
@@ -0,0 +1,14 @@
+// Test that -Wunused should not emit a warning on the initialization of
+// non-POD arrays. See PR c++/39803.
+// { dg-do compile }
+// { dg-options "-Wunused" }
+
+#include <utility>
+
+using std::pair;
+
+int foo() {
+  pair<int, const char*> components[3]; // { dg-bogus "value computed is not used" }
+  components[0].first = 0;
+  return 0;
+}