Re: [PING]: PATCH: PR tree-optimization/35494: [4.4 Regression]: Revision 132991 breaks C++ static member

["H.J. Lu" <hjl dot tools at gmail dot com>]

On Mon, Mar 10, 2008 at 7:55 AM, H.J. Lu <hjl.tools@gmail.com> wrote:
> The current C++ compiler breaks C++ data member:
>
>  http://gcc.gnu.org/bugzilla/show_bug.cgi?id=35494
>
>  The current patch is at
>
>  http://gcc.gnu.org/ml/gcc-patches/2008-03/msg00572.html
>
>  It passed all tests on Linux/x86 and Linux/Intel64 as well as
>  483.xalancbmk. OK to install?
>

Here is a smaller patch just for PR 35494. I am testing it on
Linux/x86 and Linux/Intel64 as well as 483.xalancbmk. OK to
install if all pases?

H.J.

gcc/

2008-03-08  H.J. Lu  <hongjiu.lu@intel.com>

	PR tree-optimization/35494
	* tree-ssa-ccp.c (get_symbol_constant_value): Check if value
	may be overriden at link and run time.

gcc/testsuite/

2008-03-07  H.J. Lu  <hongjiu.lu@intel.com>

	PR tree-optimization/35494
	* g++.dg/tree-ssa/ssa-store-ccp-1.C: New.
	* gcc.dg/tree-ssa/ssa-store-ccp-2.c: Likewise.
	* gcc.dg/tree-ssa/ssa-store-ccp-3.c: Likewise.
	* gcc.dg/tree-ssa/ssa-store-ccp-4.c: Likewise.

--- gcc/testsuite/g++.dg/tree-ssa/ssa-store-ccp-1.C.local	2008-03-08 18:11:53.000000000 -0800
+++ gcc/testsuite/g++.dg/tree-ssa/ssa-store-ccp-1.C	2008-03-08 18:11:53.000000000 -0800
@@ -0,0 +1,19 @@
+/* { dg-do compile } */
+/* { dg-options "-O2 -fdump-tree-optimized" } */
+
+class bar
+{
+public:
+  static const int conststaticvariable;
+};
+
+
+int f(void)
+{
+  return bar::conststaticvariable;
+}
+
+/* There should be a reference to conststaticvariable since it may
+   be overriden at link time.  */
+/* { dg-final { scan-tree-dump-times "conststaticvariable" 1 "optimized"} } */
+/* { dg-final { cleanup-tree-dump "optimized" } } */
--- gcc/testsuite/gcc.dg/tree-ssa/ssa-store-ccp-2.c.local	2008-03-08 18:11:53.000000000 -0800
+++ gcc/testsuite/gcc.dg/tree-ssa/ssa-store-ccp-2.c	2008-03-08 18:11:53.000000000 -0800
@@ -0,0 +1,14 @@
+/* { dg-do compile } */
+/* { dg-options "-O2 -fdump-tree-optimized" } */
+
+const int conststaticvariable;
+
+int f(void)
+{
+  return conststaticvariable;
+}
+
+/* There should be a reference to conststaticvariable since it may
+   may be overriden at link time.  */
+/* { dg-final { scan-tree-dump-times "conststaticvariable" 1 "optimized"} } */
+/* { dg-final { cleanup-tree-dump "optimized" } } */
--- gcc/testsuite/gcc.dg/tree-ssa/ssa-store-ccp-3.c.local	2008-03-08 18:11:53.000000000 -0800
+++ gcc/testsuite/gcc.dg/tree-ssa/ssa-store-ccp-3.c	2008-03-08 18:11:53.000000000 -0800
@@ -0,0 +1,14 @@
+/* { dg-do compile } */
+/* { dg-options "-O2 -fno-common -fdump-tree-optimized" } */
+
+const int conststaticvariable;
+
+int f(void)
+{
+  return conststaticvariable;
+}
+
+/* There should be no reference to conststaticvariable as we should have
+   inlined the 0. */
+/* { dg-final { scan-tree-dump-times "conststaticvariable" 0 "optimized"} } */
+/* { dg-final { cleanup-tree-dump "optimized" } } */
--- gcc/testsuite/gcc.dg/tree-ssa/ssa-store-ccp-4.c.local	2008-03-08 18:11:53.000000000 -0800
+++ gcc/testsuite/gcc.dg/tree-ssa/ssa-store-ccp-4.c	2008-03-08 18:11:53.000000000 -0800
@@ -0,0 +1,15 @@
+/* { dg-do compile } */
+/* { dg-require-effective-target fpic } */
+/* { dg-options "-O2 -fno-common -fpic -fdump-tree-optimized" } */
+
+const int conststaticvariable;
+
+int f(void)
+{
+  return conststaticvariable;
+}
+
+/* There should be a reference to conststaticvariable since it may
+   may be overriden at run time.  */
+/* { dg-final { scan-tree-dump-times "conststaticvariable" 1 "optimized"} } */
+/* { dg-final { cleanup-tree-dump "optimized" } } */
--- gcc/tree-ssa-ccp.c.local	2008-03-07 09:02:37.000000000 -0800
+++ gcc/tree-ssa-ccp.c	2008-03-09 06:58:50.000000000 -0700
@@ -300,7 +300,10 @@ get_symbol_constant_value (tree sym)
 {
   if (TREE_STATIC (sym)
       && TREE_READONLY (sym)
-      && !MTAG_P (sym))
+      && !MTAG_P (sym)
+      /* Check if a read-only definition may be overridden at
+	 link and run time.  */
+      && targetm.binds_local_p (sym))
     {
       tree val = DECL_INITIAL (sym);
       if (val