--- old/src/hotspot/share/classfile/sharedPathsMiscInfo.cpp	2018-05-16 22:33:44.899208329 -0400
+++ new/src/hotspot/share/classfile/sharedPathsMiscInfo.cpp	2018-05-16 22:33:43.175108468 -0400
@@ -28,6 +28,7 @@
 #include "logging/log.hpp"
 #include "logging/logStream.hpp"
 #include "memory/allocation.inline.hpp"
+#include "memory/filemap.hpp"
 #include "memory/metaspaceShared.hpp"
 #include "memory/resourceArea.hpp"
 #include "runtime/arguments.hpp"
@@ -140,12 +141,66 @@
   return true;
 }
 
+char* skip_first_path_entry(const char* path) {
+  size_t path_sep_len = strlen(os::path_separator());
+  char* p = strstr((char*)path, os::path_separator());
+  if (p != NULL) {
+    p += path_sep_len;
+  }
+  return p;
+}
+
 bool SharedPathsMiscInfo::check(jint type, const char* path) {
+  assert(UseSharedSpaces, "runtime only");
   switch (type) {
   case BOOT_PATH:
-    // In the future we should perform the check based on the content of the mapped archive.
-    if (os::file_name_strcmp(path, Arguments::get_sysclasspath()) != 0) {
-      return fail("[BOOT classpath mismatch, actual =", Arguments::get_sysclasspath());
+    {
+      //
+      // - Archive contains boot classes only - relaxed boot path check:
+      //   Extra path elements appended to the boot path at runtime are allowed.
+      //
+      // - Archive contains application or platform classes - strict boot path check:
+      //   Validate the entire runtime boot path, which must be compactible
+      //   with the dump time boot path. Appending boot path at runtime is not
+      //   allowed.
+      //
+
+      // The first entry in boot path is the modules_image (guaranteed by
+      // ClassLoader::setup_boot_search_path()). Skip the first entry. The
+      // path of the runtime modules_image may be different from the dump
+      // time path (e.g. the JDK image is copied to a different location
+      // after generating the shared archive), which is acceptable. For most
+      // common cases, the dump time boot path might contain modules_image only.
+      char* runtime_boot_path = Arguments::get_sysclasspath();
+      char* rp = skip_first_path_entry(runtime_boot_path);
+      char* dp = skip_first_path_entry(path);
+
+      bool relaxed_check = !FileMapInfo::current_info()->header()->has_platform_or_app_classes();
+      if (dp == NULL && rp == NULL) {
+        break;   // ok, both runtime and dump time boot paths have modules_images only
+      } else if (dp == NULL && rp != NULL && relaxed_check) {
+        break;   // ok, relaxed check, runtime has extra boot append path entries
+      } else if (dp != NULL && rp != NULL) {
+        ResourceMark rm;
+        char* checked_rp;
+        if (relaxed_check) {
+          // only check the leading entries in the runtime boot path, up to
+          // the length of the dump time boot path
+          size_t len = strlen(dp);
+          checked_rp = NEW_RESOURCE_ARRAY(char, len + 1);
+          strncpy(checked_rp, rp, len);
+          checked_rp[len] = '\0';
+        } else {
+          checked_rp = rp;
+        }
+
+        if (os::file_name_strcmp(dp, checked_rp) == 0) {
+          break; // ok, runtime and dump time paths match
+        }
+      }
+
+      // The paths are different
+      return fail("[BOOT classpath mismatch, actual =", runtime_boot_path);
     }
     break;
   case NON_EXIST: