re PR c++/23099 (ICE in build_simple_base_path, at cp/class.c:460)

	PR c++/23099
	* cp-tree.h (saved_scope): Add skip_evaluation.
	* decl.c (start_decl): Use DECL_INITIALIZED_IN_CLASS_P, not
	DECL_INITIAL, to determine whether or not a static data member was
	initialized in the class-specifier.
	(cp_finish_decl): Add comment.
	* init.c (integral_constant_value): Subtitute into the
	initializers for static data members in	templates.
	* name-lookup.c (push_to_top_level): Save skip_evaluation.
	(pop_from_top_level): Restore it.
	* pt.c (instantiate_class_template): Do not substitute into the
	intializers of static data members when instantiating a class.
	(regenerate_decl_from_template): Simplify.
	(instantiate_decl): Tidy.  Substitute into the initializer for a
	static data member even when the definition of the data member is
	not available.

	PR c++/23099
	* g++.dg/init/member1.C: Make sure erroneous static data member
	definitions are required.
	* g++.dg/template/static13.C: New test.
	* g++.dg/template/static14.C: Likewise.

From-SVN: r103604

1 files changed, 19 insertions, 6 deletions

diff --git a/gcc/cp/init.c b/gcc/cp/init.c
index 690e35f..8a8dc78 100644
--- a/gcc/cp/init.c
+++ b/gcc/cp/init.c
@@ -1572,12 +1572,25 @@ integral_constant_value (tree decl)
 	      /* And so are variables with a 'const' type -- unless they
 		 are also 'volatile'.  */
 	      && CP_TYPE_CONST_NON_VOLATILE_P (TREE_TYPE (decl))
-	      && DECL_INITIALIZED_BY_CONSTANT_EXPRESSION_P (decl)))
-	 && DECL_INITIAL (decl)
-	 && DECL_INITIAL (decl) != error_mark_node
-	 && TREE_TYPE (DECL_INITIAL (decl))
-	 && INTEGRAL_OR_ENUMERATION_TYPE_P (TREE_TYPE (DECL_INITIAL (decl))))
-    decl = DECL_INITIAL (decl);
+	      && DECL_INITIALIZED_BY_CONSTANT_EXPRESSION_P (decl))))
+    {
+      tree init;
+      /* If DECL is a static data member in a template class, we must
+	 instantiate it here.  The initializer for the static data
+	 member is not processed until needed; we need it now.  */ 
+      mark_used (decl);
+      init = DECL_INITIAL (decl);
+      /* If we are currently processing a template, the
+	 initializer for a static data member may not be dependent,
+	 but it is not folded until instantiation time.  */
+      if (init)
+	init = fold_non_dependent_expr (init);
+      if (!(init || init == error_mark_node)
+	  || !TREE_TYPE (init)
+	  || !INTEGRAL_OR_ENUMERATION_TYPE_P (TREE_TYPE (init)))
+	break;
+      decl = init;
+    }
   return decl;
 }