diff -r f69cfe79fe98 -r 943cf01a6b82 hotspot/src/share/vm/runtime/arguments.hpp
--- a/hotspot/src/share/vm/runtime/arguments.hpp	Tue Jul 26 11:04:20 2016 +0200
+++ b/hotspot/src/share/vm/runtime/arguments.hpp	Tue Jul 26 10:29:27 2016 -0400
@@ -363,6 +363,9 @@
   // -Xbootclasspath/p was supported.
   static PathString *_system_boot_class_path;
 
+  // Set if a modular java runtime image is present vs. a build with exploded modules
+  static bool _has_jimage;
+
   // temporary: to emit warning if the default ext dirs are not empty.
   // remove this variable when the warning is no longer needed.
   static char* _ext_dirs;
@@ -411,11 +414,6 @@
   static void set_java_compiler(bool arg) { _java_compiler = arg; }
   static bool java_compiler()   { return _java_compiler; }
 
-  // Capture the index location of -Xbootclasspath\a within sysclasspath.
-  // Used when setting up the bootstrap search path in order to
-  // mark the boot loader's append path observability boundary.
-  static int _bootclassloader_append_index;
-
   // -Xdebug flag
   static bool _xdebug_mode;
   static void set_xdebug_mode(bool arg) { _xdebug_mode = arg; }
@@ -669,17 +667,6 @@
   static size_t min_heap_size()             { return _min_heap_size; }
   static void  set_min_heap_size(size_t v)  { _min_heap_size = v;  }
 
-  // -Xbootclasspath/a
-  static int  bootclassloader_append_index() {
-    return _bootclassloader_append_index;
-  }
-  static void set_bootclassloader_append_index(int value) {
-    // Set only if the index has not been set yet
-    if (_bootclassloader_append_index == -1) {
-      _bootclassloader_append_index = value;
-    }
-  }
-
   // -Xrun
   static AgentLibrary* libraries()          { return _libraryList.first(); }
   static bool init_libraries_at_startup()   { return !_libraryList.is_empty(); }
@@ -739,19 +726,21 @@
 
   // Set up the underlying pieces of the system boot class path
   static void add_xpatchprefix(const char *module_name, const char *path, bool* xpatch_javabase);
-  static void set_sysclasspath(const char *value) {
+  static void set_sysclasspath(const char *value, bool has_jimage) {
+    // During start up, set by os::set_boot_path()
+    assert(get_sysclasspath() == NULL, "System boot class path previously set");
     _system_boot_class_path->set_value(value);
-    set_jdkbootclasspath_append();
+    _has_jimage = has_jimage;
   }
   static void append_sysclasspath(const char *value) {
     _system_boot_class_path->append_value(value);
-    set_jdkbootclasspath_append();
+    _jdk_boot_class_path_append->append_value(value);
   }
-  static void set_jdkbootclasspath_append();
 
   static GrowableArray<ModuleXPatchPath*>* get_xpatchprefix() { return _xpatchprefix; }
   static char* get_sysclasspath() { return _system_boot_class_path->value(); }
   static char* get_jdk_boot_class_path_append() { return _jdk_boot_class_path_append->value(); }
+  static bool has_jimage() { return _has_jimage; }
 
   static char* get_java_home()    { return _java_home->value(); }
   static char* get_dll_dir()      { return _sun_boot_library_path->value(); }