decl.c (add_binding): Handle duplicate declarations of external variables.

	* decl.c (add_binding): Handle duplicate declarations of external
	variables.

From-SVN: r34489

gcc/cp/ChangeLog

+2000-06-10  Mark Mitchell  <mark@codesourcery.com>
+
+	* decl.c (add_binding): Handle duplicate declarations of external
+	variables.
+
 2000-06-09  Chip Salzenberg  <chip@valinux.com>
 	    Mark Mitchell <mark@codesourcery.com>
 

gcc/cp/decl.c

@@ -1032,6 +1032,16 @@ add_binding (id, decl)
 	 the name of any type declared in that scope to refer to the
 	 type to which it already refers.  */
     ok = 0;
+  /* There can be two block-scope declarations of the same variable,
+     so long as they are `extern' declarations.  */
+  else if (TREE_CODE (decl) == VAR_DECL
+	   && TREE_CODE (BINDING_VALUE (binding)) == VAR_DECL
+	   && DECL_EXTERNAL (decl)
+	   && DECL_EXTERNAL (BINDING_VALUE (binding)))
+    {
+      duplicate_decls (decl, BINDING_VALUE (binding));
+      ok = 0;
+    }
   else
     {
       cp_error ("declaration of `%#D'", decl);

gcc/testsuite/g++.old-deja/g++.other/decl8.C

+// Build don't link:
+// Origin: Sergei Organov <osv@javad.ru>
+
+void foo(void)
+{
+  extern int i;    // ERROR - previous declaration
+  extern double i; // ERROR - conflicting type
+  extern int j;
+  extern int j;
+}