[Bug #18329] Fix crash when calling non-existent super method

The cme is NULL when a method does not exist, so check it before
accessing the callcache.

test/ruby/test_super.rb

@@ -521,6 +521,37 @@ class TestSuper < Test::Unit::TestCase
     assert_equal(%w[B A], result, bug9721)
   end
 
+  # [Bug #18329]
+  def test_super_missing_prepended_module
+    a = Module.new do
+      def probe(*methods)
+        prepend(probing_module(methods))
+      end
+
+      def probing_module(methods)
+        Module.new do
+          methods.each do |method|
+            define_method(method) do |*args, **kwargs, &block|
+              super(*args, **kwargs, &block)
+            end
+          end
+        end
+      end
+    end
+
+    b = Class.new do
+      extend a
+
+      probe :danger!, :missing
+
+      def danger!; end
+    end
+
+    o = b.new
+    o.danger!
+    2.times { o.missing rescue NoMethodError }
+  end
+
   def test_from_eval
     bug10263 = '[ruby-core:65122] [Bug #10263a]'
     a = Class.new do

vm_insnhelper.c

@@ -1936,7 +1936,8 @@ vm_search_method_fastpath(VALUE cd_owner, struct rb_call_data *cd, VALUE klass)
 
 #if OPT_INLINE_METHOD_CACHE
     if (LIKELY(vm_cc_class_check(cc, klass))) {
-        if (LIKELY(!METHOD_ENTRY_INVALIDATED(vm_cc_cme(cc)))) {
+        const struct rb_callable_method_entry_struct *cme = vm_cc_cme(cc);
+        if (LIKELY(cme && !METHOD_ENTRY_INVALIDATED(cme))) {
             VM_ASSERT(callable_method_entry_p(vm_cc_cme(cc)));
             RB_DEBUG_COUNTER_INC(mc_inline_hit);
             VM_ASSERT(vm_cc_cme(cc) == NULL ||                        // not found