1 files changed, 46 insertions, 0 deletions
diff --git a/libgo/runtime/go-check-interface.c b/libgo/runtime/go-check-interface.c
new file mode 100644
index 000000000..d2258a854
--- /dev/null
+++ b/libgo/runtime/go-check-interface.c
@@ -0,0 +1,46 @@
+/* go-check-interface.c -- check an interface type for a conversion
+
+   Copyright 2010 The Go Authors. All rights reserved.
+   Use of this source code is governed by a BSD-style
+   license that can be found in the LICENSE file.  */
+
+#include "go-panic.h"
+#include "interface.h"
+
+/* Check that an interface type matches for a conversion to a
+   non-interface type.  This panics if the types are bad.  The actual
+   extraction of the object is inlined.  */
+
+void
+__go_check_interface_type (
+    const struct __go_type_descriptor *lhs_descriptor,
+    const struct __go_type_descriptor *rhs_descriptor,
+    const struct __go_type_descriptor *rhs_inter_descriptor)
+{
+  if (rhs_descriptor == NULL)
+    {
+      struct __go_empty_interface panic_arg;
+
+      newTypeAssertionError(NULL, NULL, lhs_descriptor, NULL, NULL,
+			    lhs_descriptor->__reflection, NULL, &panic_arg);
+      __go_panic(panic_arg);
+    }
+
+  if (lhs_descriptor != rhs_descriptor
+      && !__go_type_descriptors_equal (lhs_descriptor, rhs_descriptor)
+      && (lhs_descriptor->__code != GO_UNSAFE_POINTER
+	  || !__go_is_pointer_type (rhs_descriptor))
+      && (rhs_descriptor->__code != GO_UNSAFE_POINTER
+	  || !__go_is_pointer_type (lhs_descriptor)))
+    {
+      struct __go_empty_interface panic_arg;
+
+      newTypeAssertionError(rhs_inter_descriptor, rhs_descriptor,
+			    lhs_descriptor,
+			    rhs_inter_descriptor->__reflection,
+			    rhs_descriptor->__reflection,
+			    lhs_descriptor->__reflection,
+			    NULL, &panic_arg);
+      __go_panic(panic_arg);
+    }
+}