From: Mark Mitchell <mark@codesourcery.com>
Date: Tue, 6 Jan 2004 00:52:10 +0000 (+0000)
Subject: re PR c++/12815 (Code compiled with optimization behaves unexpectedly)
X-Git-Tag: releases/gcc-3.4.0~1257
X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=962c0823997cba18cca85efec200b19fac8e2c87;p=thirdparty%2Fgcc.git

re PR c++/12815 (Code compiled with optimization behaves unexpectedly)

	PR c++/12816
	* class.c (build_vtbl_ref_1): Do not unconditionally mark vtable
	references as constant.

	PR c++/12815
	* g++.dg/rtti/typeid4.C: New test.

From-SVN: r75457
---

diff --git a/gcc/cp/ChangeLog b/gcc/cp/ChangeLog
index 3a6a6ae44b58..b428cee8b4c4 100644
--- a/gcc/cp/ChangeLog
+++ b/gcc/cp/ChangeLog
@@ -1,5 +1,9 @@
 2004-01-05  Mark Mitchell  <mark@codesourcery.com>
 
+	PR c++/12816
+	* class.c (build_vtbl_ref_1): Do not unconditionally mark vtable
+	references as constant.
+
 	PR c++/12132
 	* parser.c (cp_parser_explicit_instantiation): Improve error
 	recovery.
diff --git a/gcc/cp/class.c b/gcc/cp/class.c
index 2928dd330710..31c6d2291d99 100644
--- a/gcc/cp/class.c
+++ b/gcc/cp/class.c
@@ -455,7 +455,7 @@ build_vtbl_ref_1 (tree instance, tree idx)
   assemble_external (vtbl);
 
   aref = build_array_ref (vtbl, idx);
-  TREE_CONSTANT (aref) = 1;
+  TREE_CONSTANT (aref) |= TREE_CONSTANT (vtbl) && TREE_CONSTANT (idx);
 
   return aref;
 }
diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog
index 3741b3bce481..d9c510868de3 100644
--- a/gcc/testsuite/ChangeLog
+++ b/gcc/testsuite/ChangeLog
@@ -1,3 +1,8 @@
+2004-01-05  Mark Mitchell  <mark@codesourcery.com>
+
+	PR c++/12815
+	* g++.dg/rtti/typeid4.C: New test.
+
 2004-01-05  Eric Botcazou  <ebotcazou@libertysurf.fr>
 
 	* gcc.dg/compat/sdata-section.h: Declare 'abort'.
diff --git a/gcc/testsuite/g++.dg/rtti/typeid4.C b/gcc/testsuite/g++.dg/rtti/typeid4.C
new file mode 100644
index 000000000000..e6a1dce16f0e
--- /dev/null
+++ b/gcc/testsuite/g++.dg/rtti/typeid4.C
@@ -0,0 +1,26 @@
+// { dg-do run }
+// { dg-options "-O2" }
+
+#include <typeinfo>
+#include <iostream>
+
+struct A { virtual ~A () {} };
+
+struct APtr
+{ 
+  APtr (A* p)  : p_ (p) { }
+  A& operator* () const { return *p_; }
+  A* p_;
+};
+
+int main ()
+{ 
+  APtr ap (new A);
+  std::type_info const* const exp = &typeid (*ap);
+  for (bool cont = true; cont; cont = false)
+    { 
+      std::cout << "inner: cont " << cont << std::endl;
+      if (exp) ;
+    }
+}
+