Revamp foreign code not to consider the Rust modes. This requires

src/libcore/os.rs

@@ -61,7 +61,7 @@ pub mod rustrt {
         unsafe fn rust_getcwd() -> ~str;
         unsafe fn rust_path_is_dir(path: *libc::c_char) -> c_int;
         unsafe fn rust_path_exists(path: *libc::c_char) -> c_int;
-        unsafe fn rust_list_files2(&&path: ~str) -> ~[~str];
+        unsafe fn rust_list_files2(path: &~str) -> ~[~str];
         unsafe fn rust_process_wait(handle: c_int) -> c_int;
         unsafe fn rust_set_exit_status(code: libc::intptr_t);
     }
@@ -621,7 +621,8 @@ pub fn list_dir(p: &Path) -> ~[~str] {
         #[cfg(windows)]
         fn star(p: &Path) -> Path { p.push("*") }
 
-        do rustrt::rust_list_files2(star(p).to_str()).filtered |filename| {
+        let s = star(p).to_str();
+        do rustrt::rust_list_files2(&s).filtered |filename| {
             *filename != ~"." && *filename != ~".."
         }
     }

src/libcore/unstable.rs

@@ -45,7 +45,7 @@ mod rustrt {
         pub unsafe fn rust_lock_little_lock(lock: rust_little_lock);
         pub unsafe fn rust_unlock_little_lock(lock: rust_little_lock);
 
-        pub unsafe fn rust_raw_thread_start(f: &fn()) -> *raw_thread;
+        pub unsafe fn rust_raw_thread_start(f: &(&fn())) -> *raw_thread;
         pub unsafe fn rust_raw_thread_join_delete(thread: *raw_thread);
     }
 }
@@ -70,7 +70,7 @@ pub unsafe fn run_in_bare_thread(f: ~fn()) {
             let closure: &fn() = || {
                 f()
             };
-            let thread = rustrt::rust_raw_thread_start(closure);
+            let thread = rustrt::rust_raw_thread_start(&closure);
             rustrt::rust_raw_thread_join_delete(thread);
             chan.send(());
         }

src/librustc/middle/lint.rs

@@ -77,6 +77,7 @@ pub enum lint {
     default_methods,
     deprecated_self,
     deprecated_mutable_fields,
+    foreign_mode,
 
     managed_heap_memory,
     owned_heap_memory,
@@ -181,6 +182,13 @@ pub fn get_lint_dict() -> LintDict {
             default: warn
          }),
 
+        (@~"foreign_mode",
+         @LintSpec {
+            lint: foreign_mode,
+            desc: "warn about deprecated uses of modes in foreign fns",
+            default: warn
+         }),
+
         (@~"deprecated_pattern",
          @LintSpec {
             lint: deprecated_pattern,
@@ -724,6 +732,20 @@ fn check_item_ctypes(cx: ty::ctxt, it: @ast::item) {
 
     fn check_foreign_fn(cx: ty::ctxt, fn_id: ast::node_id,
                         decl: &ast::fn_decl) {
+        // warn about `&&` mode on foreign functions, both because it is
+        // deprecated and because its semantics have changed recently:
+        for decl.inputs.eachi |i, arg| {
+            match ty::resolved_mode(cx, arg.mode) {
+                ast::by_val | ast::by_copy => {}
+                ast::by_ref => {
+                    cx.sess.span_lint(
+                        foreign_mode, fn_id, fn_id, arg.ty.span,
+                        fmt!("foreign function uses `&&` mode \
+                              on argument %u", i));
+                }
+            }
+        }
+
         let tys = vec::map(decl.inputs, |a| a.ty );
         for vec::each(vec::append_one(tys, decl.output)) |ty| {
             match ty.node {
@@ -756,7 +778,7 @@ fn check_item_ctypes(cx: ty::ctxt, it: @ast::item) {
       if attr::foreign_abi(it.attrs) !=
             either::Right(ast::foreign_abi_rust_intrinsic) => {
         for nmod.items.each |ni| {
-            match /*bad*/copy ni.node {
+            match ni.node {
               ast::foreign_item_fn(ref decl, _, _) => {
                 check_foreign_fn(cx, it.id, decl);
               }

src/librustc/middle/trans/callee.rs

@@ -757,7 +757,7 @@ pub fn trans_arg_expr(bcx: block,
 
         if formal_ty.ty != arg_datum.ty {
             // this could happen due to e.g. subtyping
-            let llformal_ty = type_of::type_of_explicit_arg(ccx, formal_ty);
+            let llformal_ty = type_of::type_of_explicit_arg(ccx, &formal_ty);
             debug!("casting actual type (%s) to match formal (%s)",
                    bcx.val_str(val), bcx.llty_str(llformal_ty));
             val = PointerCast(bcx, val, llformal_ty);