From: Jakub Jelinek <jakub@redhat.com>
Date: Mon, 20 Aug 2007 08:10:54 +0000 (+0200)
Subject: re PR c++/32992 (Incorrect code generated for anonymous union and return)
X-Git-Tag: releases/gcc-4.2.2~139
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=c00d7caf0acb1154860d92a964f426e9f36f980d;p=thirdparty%2Fgcc.git

re PR c++/32992 (Incorrect code generated for anonymous union and return)

	PR c++/32992
	* typeck.c (check_return_expr): Don't NRV optimize vars in
	anonymous unions.
	* decl.c (finish_function): Comment fix.

	* g++.dg/opt/nrv14.C: New test.

From-SVN: r127640
---

diff --git a/gcc/cp/ChangeLog b/gcc/cp/ChangeLog
index 953f47eb81d9..6601d8055949 100644
--- a/gcc/cp/ChangeLog
+++ b/gcc/cp/ChangeLog
@@ -1,3 +1,10 @@
+2007-08-20  Jakub Jelinek  <jakub@redhat.com>
+
+	PR c++/32992
+	* typeck.c (check_return_expr): Don't NRV optimize vars in
+	anonymous unions.
+	* decl.c (finish_function): Comment fix.
+
 2007-08-18  Paolo Carlini  <pcarlini@suse.de>
 
 	PR c++/32112
diff --git a/gcc/cp/decl.c b/gcc/cp/decl.c
index 28e653b0751e..b837b1451538 100644
--- a/gcc/cp/decl.c
+++ b/gcc/cp/decl.c
@@ -11273,7 +11273,7 @@ finish_function (int flags)
   gcc_assert (stmts_are_full_exprs_p ());
 
   /* Set up the named return value optimization, if we can.  Candidate
-     variables are selected in check_return_value.  */
+     variables are selected in check_return_expr.  */
   if (current_function_return_value)
     {
       tree r = current_function_return_value;
diff --git a/gcc/cp/typeck.c b/gcc/cp/typeck.c
index 4ae2f073abde..6f0777274cef 100644
--- a/gcc/cp/typeck.c
+++ b/gcc/cp/typeck.c
@@ -6604,6 +6604,7 @@ check_return_expr (tree retval, bool *no_warning)
 	  && TREE_CODE (retval) == VAR_DECL
 	  && DECL_CONTEXT (retval) == current_function_decl
 	  && ! TREE_STATIC (retval)
+	  && ! DECL_ANON_UNION_VAR_P (retval)
 	  && (DECL_ALIGN (retval)
 	      >= DECL_ALIGN (DECL_RESULT (current_function_decl)))
 	  && same_type_p ((TYPE_MAIN_VARIANT
diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog
index 50cf8c961482..b78ef3f76185 100644
--- a/gcc/testsuite/ChangeLog
+++ b/gcc/testsuite/ChangeLog
@@ -1,3 +1,8 @@
+2007-08-20  Jakub Jelinek  <jakub@redhat.com>
+
+	PR c++/32992
+	* g++.dg/opt/nrv14.C: New test.
+
 2007-08-18  Paolo Carlini  <pcarlini@suse.de>
 
 	PR c++/32112
diff --git a/gcc/testsuite/g++.dg/opt/nrv14.C b/gcc/testsuite/g++.dg/opt/nrv14.C
new file mode 100644
index 000000000000..22526d6b59a4
--- /dev/null
+++ b/gcc/testsuite/g++.dg/opt/nrv14.C
@@ -0,0 +1,39 @@
+// PR c++/32992
+// { dg-do run }
+// { dg-options "-O2" }
+
+extern "C" void abort (void);
+
+struct A
+{
+  long int a1;
+  long int a2;
+  long int a3;
+};
+
+struct B
+{
+  long int f[3];
+  operator A ()
+  {
+    union
+    {
+      long int t[3];
+      A a;
+    };
+    for (int i = 0; i < 3; i++)
+      t[i] = f[i];
+    return a;
+  }
+};
+
+int
+main ()
+{
+  B b = { {1, 3, 5} };
+  A a = b;
+
+  if (a.a1 != b.f[0] || a.a2 != b.f[1] || a.a3 != b.f[2])
+    abort ();
+  return 0;
+}