--- old/src/hotspot/share/memory/filemap.cpp	2018-05-13 20:25:26.951790489 -0400
+++ new/src/hotspot/share/memory/filemap.cpp	2018-05-13 20:25:25.655715552 -0400
@@ -206,6 +206,7 @@
 }
 
 void SharedClassPathEntry::init(const char* name, TRAPS) {
+  assert(DumpSharedSpaces, "dump time only");
   _timestamp = 0;
   _filesize  = 0;
 
@@ -215,7 +216,10 @@
       _is_dir = true;
     } else {
       _is_dir = false;
-      _timestamp = st.st_mtime;
+      // The timestamp of the modules_image is not checked at runtime.
+      if (!ClassLoader::is_modules_image(name)) {
+        _timestamp = st.st_mtime;
+      }
       _filesize = st.st_size;
     }
   } else {
@@ -237,6 +241,15 @@
 
   struct stat st;
   const char* name = this->name();
+
+  // We need to validate the runtime modules image file size against the archived
+  // size information, obtain the runtime modules image path. The recorded dump
+  // time modules image path in the archive may be different from the runtime path
+  // if the JDK image has beed moved after generating the archive.
+  if (ClassLoader::is_modules_image(name)) {
+    name = ClassLoader::get_jrt_entry()->name();
+  }
+
   bool ok = true;
   log_info(class, path)("checking shared classpath entry: %s", name);
   if (os::stat(name, &st) != 0 && is_class_path) {
@@ -251,18 +264,16 @@
       FileMapInfo::fail_continue("directory is not empty: %s", name);
       ok = false;
     }
-  } else if (is_jar_or_bootimage()) {
-    if (_timestamp != st.st_mtime ||
-        _filesize != st.st_size) {
-      ok = false;
-      if (PrintSharedArchiveAndExit) {
-        FileMapInfo::fail_continue(_timestamp != st.st_mtime ?
-                                   "Timestamp mismatch" :
-                                   "File size mismatch");
-      } else {
-        FileMapInfo::fail_continue("A jar/jimage file is not the one used while building"
-                                   " the shared archive file: %s", name);
-      }
+  } else if ((has_timestamp() && _timestamp != st.st_mtime) ||
+             _filesize != st.st_size) {
+    ok = false;
+    if (PrintSharedArchiveAndExit) {
+      FileMapInfo::fail_continue(_timestamp != st.st_mtime ?
+                                 "Timestamp mismatch" :
+                                 "File size mismatch");
+    } else {
+      FileMapInfo::fail_continue("A jar file is not the one used while building"
+                                 " the shared archive file: %s", name);
     }
   }
   return ok;