--- a/src/hotspot/share/classfile/classLoader.cpp	Sat Mar 23 17:18:49 2019 +0100
+++ b/src/hotspot/share/classfile/classLoader.cpp	Sat Mar 23 21:51:07 2019 -0700
@@ -361,6 +361,8 @@
   }
 }
 
+DEBUG_ONLY(ClassPathImageEntry* ClassPathImageEntry::_singleton = NULL;)
+
 void ClassPathImageEntry::close_jimage() {
   if (_jimage != NULL) {
     (*JImageClose)(_jimage);
@@ -373,12 +375,17 @@
   _jimage(jimage) {
   guarantee(jimage != NULL, "jimage file is null");
   guarantee(name != NULL, "jimage file name is null");
+  assert(_singleton == NULL, "VM supports only one jimage");
+  DEBUG_ONLY(_singleton = this);
   size_t len = strlen(name) + 1;
   _name = NEW_C_HEAP_ARRAY(const char, len, mtClass);
   strncpy((char *)_name, name, len);
 }
 
 ClassPathImageEntry::~ClassPathImageEntry() {
+  assert(_singleton == this, "must be");
+  DEBUG_ONLY(_singleton = NULL);
+
   if (_name != NULL) {
     FREE_C_HEAP_ARRAY(const char, _name);
     _name = NULL;
@@ -442,10 +449,12 @@
     char* data = NEW_RESOURCE_ARRAY(char, size);
     (*JImageGetResource)(_jimage, location, data, size);
     // Resource allocated
+    assert(this == (ClassPathImageEntry*)ClassLoader::get_jrt_entry(), "must be");
     return new ClassFileStream((u1*)data,
                                (int)size,
                                _name,
-                               ClassFileStream::verify);
+                               ClassFileStream::verify,
+                               true); // from_boot_loader_modules_image
   }
 
   return NULL;
@@ -459,7 +468,9 @@
 }
 
 bool ClassPathImageEntry::is_modules_image() const {
-  return ClassLoader::is_modules_image(name());
+  assert(this == _singleton, "VM supports a single jimage");
+  assert(this == (ClassPathImageEntry*)ClassLoader::get_jrt_entry(), "must be used for jrt entry");
+  return true;
 }
 
 #if INCLUDE_CDS
@@ -737,8 +748,8 @@
         // Check for a jimage
         if (Arguments::has_jimage()) {
           assert(_jrt_entry == NULL, "should not setup bootstrap class search path twice");
+          _jrt_entry = new_entry;
           assert(new_entry != NULL && new_entry->is_modules_image(), "No java runtime image present");
-          _jrt_entry = new_entry;
           assert(_jrt_entry->jimage() != NULL, "No java runtime image");
         }
       } else {
@@ -1499,7 +1510,7 @@
       }
       // for index 0 and the stream->source() is the modules image or has the jrt: protocol.
       // The class must be from the runtime modules image.
-      if (i == 0 && (is_modules_image(src) || string_starts_with(src, "jrt:"))) {
+      if (i == 0 && (stream->from_boot_loader_modules_image() || string_starts_with(src, "jrt:"))) {
         classpath_index = i;
         break;
       }
@@ -1515,7 +1526,7 @@
     // The shared path table is set up after module system initialization.
     // The path table contains no entry before that. Any classes loaded prior
     // to the setup of the shared path table must be from the modules image.
-    assert(is_modules_image(src), "stream must be from modules image");
+    assert(stream->from_boot_loader_modules_image(), "stream must be loaded by boot loader from modules image");
     assert(FileMapInfo::get_number_of_shared_paths() == 0, "shared path table must not have been setup");
     classpath_index = 0;
   }