error.c: rb_get_backtrace

* error.c (rb_get_backtrace): move from eval_error.c to call
  exc_backtrace directly.  [ruby-core:78097] [Bug #12925]

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@56766 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

error.c

@@ -882,6 +882,22 @@ exc_backtrace(VALUE exc)
     return obj;
 }
 
+VALUE
+rb_get_backtrace(VALUE exc)
+{
+    VALUE info, klass = rb_eException;
+    ID mid = id_backtrace;
+    rb_thread_t *th = GET_THREAD();
+    if (NIL_P(exc))
+	return Qnil;
+    EXEC_EVENT_HOOK(th, RUBY_EVENT_C_CALL, exc, mid, mid, klass, Qundef);
+    info = exc_backtrace(exc);
+    EXEC_EVENT_HOOK(th, RUBY_EVENT_C_RETURN, exc, mid, mid, klass, info);
+    if (NIL_P(info))
+	return Qnil;
+    return rb_check_backtrace(info);
+}
+
 /*
  *  call-seq:
  *     exception.backtrace_locations    -> array

eval.c

@@ -507,7 +507,7 @@ setup_exception(rb_thread_t *th, int tag, volatile VALUE mesg, VALUE cause)
 		rb_ivar_set(mesg, idBt_locations, at);
 	    }
 	}
-	else if (NIL_P(get_backtrace(mesg))) {
+	else if (NIL_P(rb_get_backtrace(mesg))) {
 	    at = rb_vm_backtrace_object();
 	    if (OBJ_FROZEN(mesg)) {
 		mesg = rb_obj_dup(mesg);
@@ -1616,7 +1616,7 @@ errat_getter(ID id)
 {
     VALUE err = get_errinfo();
     if (!NIL_P(err)) {
-	return get_backtrace(err);
+	return rb_get_backtrace(err);
     }
     else {
 	return Qnil;

eval_error.c

@@ -49,23 +49,6 @@ error_pos_str(void)
     return Qnil;
 }
 
-static VALUE
-get_backtrace(VALUE info)
-{
-    if (NIL_P(info))
-	return Qnil;
-    info = rb_funcall(info, rb_intern("backtrace"), 0);
-    if (NIL_P(info))
-	return Qnil;
-    return rb_check_backtrace(info);
-}
-
-VALUE
-rb_get_backtrace(VALUE info)
-{
-    return get_backtrace(info);
-}
-
 static void
 set_backtrace(VALUE info, VALUE bt)
 {
@@ -80,7 +63,7 @@ set_backtrace(VALUE info, VALUE bt)
 	    bt = rb_backtrace_to_str_ary(bt);
 	}
     }
-    rb_funcall(info, rb_intern("set_backtrace"), 1, bt);
+    rb_check_funcall(info, set_backtrace, 1, &bt);
 }
 
 static void
@@ -105,7 +88,7 @@ rb_threadptr_error_print(rb_thread_t *th, VALUE errinfo)
 
     TH_PUSH_TAG(th);
     if (TH_EXEC_TAG() == 0) {
-	errat = get_backtrace(errinfo);
+	errat = rb_get_backtrace(errinfo);
     }
     else if (errat == Qundef) {
 	errat = Qnil;

test/ruby/test_exception.rb

@@ -952,4 +952,17 @@ $stderr = $stdout; raise "\x82\xa0"') do |outs, errs, status|
       ::Warning.warn "\x00a\x00b\x00c".force_encoding("utf-16be")
     end
   end
+
+  def test_undefined_backtrace
+    assert_separately([], "#{<<-"begin;"}\n#{<<-"end;"}")
+    begin;
+      class Exception
+        undef backtrace
+      end
+
+      assert_raise(RuntimeError) {
+        raise RuntimeError, "hello"
+      }
+    end;
+  end
 end