Put type descriptors in strings created by the runtime. Progress on #2638.

src/rt/rust_util.cpp

@@ -0,0 +1,43 @@
+#include "rust_type.h"
+#include "rust_shape.h"
+
+
+// A hardcoded type descriptor for strings, since the runtime needs to
+// be able to create them.
+
+struct rust_shape_tables empty_shape_tables;
+
+uint8_t str_body_shape[] = {
+    shape::SHAPE_UNBOXED_VEC,
+    0x1, // is_pod
+    0x1, 0x0, // size field: 1
+    shape::SHAPE_U8
+};
+
+struct type_desc str_body_tydesc = {
+    0, // unused
+    1, // size
+    1, // align
+    NULL, // take_glue
+    NULL, // drop_glue
+    NULL, // free_glue
+    NULL, // visit_glue
+    0, // unused
+    0, // unused
+    0, // unused
+    0, // unused
+    str_body_shape, // shape
+    &empty_shape_tables, // shape_tables
+    0, // unused
+    0, // unused
+};
+
+//
+// Local Variables:
+// mode: C++
+// fill-column: 78;
+// indent-tabs-mode: nil
+// c-basic-offset: 4
+// buffer-file-coding-system: utf-8-unix
+// End:
+//