---

yaml
---
r: 13116
b: refs/heads/master
c: ea8d4d7
h: refs/heads/master
v: v3

Author: msullivan

[refs]

@@ -1,5 +1,5 @@
 ---
-refs/heads/master: 1eebb1fe871addca6c7dcdfb43d0b8693e08b783
+refs/heads/master: ea8d4d7f1719a53c066713e6893b33556b69dbfe
 refs/heads/snap-stage1: e33de59e47c5076a89eadeb38f4934f58a3618a6
 refs/heads/snap-stage3: 4a81779abd786ff22d71434c6d9a5917ea4cdfff
 refs/heads/try: 2898dcc5d97da9427ac367542382b6239d9c0bbf

trunk/src/rustc/middle/trans/base.rs

@@ -2521,7 +2521,9 @@ fn trans_index(cx: block, ex: @ast::expr, base: @ast::expr,
     let ix_size = llsize_of_real(cx.ccx(), val_ty(ix.val));
     let int_size = llsize_of_real(cx.ccx(), ccx.int_type);
     let ix_val = if ix_size < int_size {
-        ZExt(bcx, ix.val, ccx.int_type)
+        if ty::type_is_signed(expr_ty(cx, idx)) {
+            SExt(bcx, ix.val, ccx.int_type)
+        } else { ZExt(bcx, ix.val, ccx.int_type) }
     } else if ix_size > int_size {
         Trunc(bcx, ix.val, ccx.int_type)
     } else {