re PR go/64238 (ICE in get_partitioning_class, at symtab.c:1775)

	PR go/64238
	* go-gcc.cc (Gcc_backend::implicit_variable_reference): Set
	DECL_EXTERNAL, clear TREE_STATIC.

From-SVN: r247937

gcc/go/ChangeLog

+2017-05-11  Ian Lance Taylor  <iant@google.com>
+
+	PR go/64238
+	* go-gcc.cc (Gcc_backend::implicit_variable_reference): Set
+	DECL_EXTERNAL, clear TREE_STATIC.
+
 2017-05-10  Than McIntosh  <thanm@google.com>
 
 	* go-backend.c: Include "go-c.h".

gcc/go/go-gcc.cc

@@ -2822,9 +2822,9 @@ Gcc_backend::implicit_variable_reference(const std::string& name,
 
   tree decl = build_decl(BUILTINS_LOCATION, VAR_DECL,
                          get_identifier_from_string(name), type_tree);
-  DECL_EXTERNAL(decl) = 0;
+  DECL_EXTERNAL(decl) = 1;
   TREE_PUBLIC(decl) = 1;
-  TREE_STATIC(decl) = 1;
+  TREE_STATIC(decl) = 0;
   DECL_ARTIFICIAL(decl) = 1;
   if (! asm_name.empty())
     SET_DECL_ASSEMBLER_NAME(decl, get_identifier_from_string(asm_name));