trans: Make collector handle the drop_in_place() intrinsic.

src/test/codegen-units/item-collection/drop_in_place_intrinsic.rs

@@ -0,0 +1,41 @@
+// Copyright 2012-2015 The Rust Project Developers. See the COPYRIGHT
+// file at the top-level directory of this distribution and at
+// http://rust-lang.org/COPYRIGHT.
+//
+// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
+// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
+// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
+// option. This file may not be copied, modified, or distributed
+// except according to those terms.
+
+// ignore-tidy-linelength
+// compile-flags:-Zprint-trans-items=eager
+
+//~ TRANS_ITEM drop-glue drop_in_place_intrinsic::StructWithDtor[0]
+//~ TRANS_ITEM drop-glue-contents drop_in_place_intrinsic::StructWithDtor[0]
+struct StructWithDtor(u32);
+
+impl Drop for StructWithDtor {
+    //~ TRANS_ITEM fn drop_in_place_intrinsic::{{impl}}[0]::drop[0]
+    fn drop(&mut self) {}
+}
+
+//~ TRANS_ITEM fn drop_in_place_intrinsic::main[0]
+fn main() {
+
+    //~ TRANS_ITEM drop-glue [drop_in_place_intrinsic::StructWithDtor[0]; 2]
+    let x = [StructWithDtor(0), StructWithDtor(1)];
+
+    drop_slice_in_place(&x);
+}
+
+//~ TRANS_ITEM fn drop_in_place_intrinsic::drop_slice_in_place[0]
+fn drop_slice_in_place(x: &[StructWithDtor]) {
+    unsafe {
+        // This is the interesting thing in this test case: Normally we would
+        // not have drop-glue for the unsized [StructWithDtor]. This has to be
+        // generated though when the drop_in_place() intrinsic is used.
+        //~ TRANS_ITEM drop-glue [drop_in_place_intrinsic::StructWithDtor[0]]
+        ::std::ptr::drop_in_place(x as *const _ as *mut [StructWithDtor]);
+    }
+}