Fix ICE trying to pass DST to C functions

Fixes #25581

Author: dotdash

src/librustc_trans/trans/callee.rs

@@ -846,7 +846,7 @@ pub fn trans_call_inner<'a, 'blk, 'tcx, F>(bcx: Block<'blk, 'tcx>,
 
         let mut llargs = Vec::new();
         let arg_tys = match args {
-            ArgExprs(a) => a.iter().map(|x| common::expr_ty(bcx, &**x)).collect(),
+            ArgExprs(a) => a.iter().map(|x| common::expr_ty_adjusted(bcx, &**x)).collect(),
             _ => panic!("expected arg exprs.")
         };
         bcx = trans_args(bcx,

src/test/run-pass/issue-25581.rs

@@ -0,0 +1,19 @@
+// Copyright 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.
+
+extern {
+    fn f(t: &[i32]);
+}
+
+fn main() {
+    unsafe {
+        f(&[0i32]);
+    }
+}