---

yaml
---
r: 123901
b: refs/heads/snap-stage3
c: f9fe251
h: refs/heads/master
i:
  123899: 9ad804f
v: v3

Author: bors

[refs]

@@ -1,7 +1,7 @@
 ---
 refs/heads/master: 4e2da7cb79143b0e7206a684629ed942599ec8e9
 refs/heads/snap-stage1: e33de59e47c5076a89eadeb38f4934f58a3618a6
-refs/heads/snap-stage3: 6f96abf7389c6a031c549a9df0b672b7989fbe8b
+refs/heads/snap-stage3: f9fe251777e9f1cc557a6d5b82b45403935d0a10
 refs/heads/try: 296eb104620b346d88bc4a2c2ab7693e6d3db019
 refs/tags/release-0.1: 1f5c5126e96c79d22cb7862f75304136e204f105
 refs/heads/ndm: f3868061cd7988080c30d6d5bf352a5a5fe2460b

branches/snap-stage3/src/libcore/iter.rs

@@ -751,6 +751,7 @@ impl<A, B, T: ExactSize<A>, U: ExactSize<B>> ExactSize<(A, B)> for Zip<T, U> {}
 
 /// An double-ended iterator with the direction inverted
 #[deriving(Clone)]
+#[must_use = "iterator adaptors are lazy and do nothing unless consumed"]
 pub struct Rev<T> {
     iter: T
 }
@@ -779,6 +780,7 @@ impl<A, T: DoubleEndedIterator<A> + RandomAccessIterator<A>> RandomAccessIterato
 }
 
 /// A mutable reference to an iterator
+#[must_use = "iterator adaptors are lazy and do nothing unless consumed"]
 pub struct ByRef<'a, T> {
     iter: &'a mut T
 }
@@ -1039,6 +1041,7 @@ impl<A, T: Clone + Iterator<A>> CloneableIterator for T {
 
 /// An iterator that repeats endlessly
 #[deriving(Clone)]
+#[must_use = "iterator adaptors are lazy and do nothing unless consumed"]
 pub struct Cycle<T> {
     orig: T,
     iter: T,
@@ -1090,6 +1093,7 @@ impl<A, T: Clone + RandomAccessIterator<A>> RandomAccessIterator<A> for Cycle<T>
 
 /// An iterator which strings two iterators together
 #[deriving(Clone)]
+#[must_use = "iterator adaptors are lazy and do nothing unless consumed"]
 pub struct Chain<T, U> {
     a: T,
     b: U,
@@ -1159,6 +1163,7 @@ for Chain<T, U> {
 
 /// An iterator which iterates two other iterators simultaneously
 #[deriving(Clone)]
+#[must_use = "iterator adaptors are lazy and do nothing unless consumed"]
 pub struct Zip<T, U> {
     a: T,
     b: U
@@ -1237,6 +1242,7 @@ RandomAccessIterator<(A, B)> for Zip<T, U> {
 }
 
 /// An iterator which maps the values of `iter` with `f`
+#[must_use = "iterator adaptors are lazy and do nothing unless consumed"]
 pub struct Map<'a, A, B, T> {
     iter: T,
     f: |A|: 'a -> B
@@ -1287,6 +1293,7 @@ impl<'a, A, B, T: RandomAccessIterator<A>> RandomAccessIterator<B> for Map<'a, A
 }
 
 /// An iterator which filters the elements of `iter` with `predicate`
+#[must_use = "iterator adaptors are lazy and do nothing unless consumed"]
 pub struct Filter<'a, A, T> {
     iter: T,
     predicate: |&A|: 'a -> bool
@@ -1331,6 +1338,7 @@ impl<'a, A, T: DoubleEndedIterator<A>> DoubleEndedIterator<A> for Filter<'a, A,
 }
 
 /// An iterator which uses `f` to both filter and map elements from `iter`
+#[must_use = "iterator adaptors are lazy and do nothing unless consumed"]
 pub struct FilterMap<'a, A, B, T> {
     iter: T,
     f: |A|: 'a -> Option<B>
@@ -1375,6 +1383,7 @@ for FilterMap<'a, A, B, T> {
 
 /// An iterator which yields the current count and the element during iteration
 #[deriving(Clone)]
+#[must_use = "iterator adaptors are lazy and do nothing unless consumed"]
 pub struct Enumerate<T> {
     iter: T,
     count: uint
@@ -1429,6 +1438,7 @@ impl<A, T: RandomAccessIterator<A>> RandomAccessIterator<(uint, A)> for Enumerat
 }
 
 /// An iterator with a `peek()` that returns an optional reference to the next element.
+#[must_use = "iterator adaptors are lazy and do nothing unless consumed"]
 pub struct Peekable<A, T> {
     iter: T,
     peeked: Option<A>,
@@ -1479,6 +1489,7 @@ impl<'a, A, T: Iterator<A>> Peekable<A, T> {
 }
 
 /// An iterator which rejects elements while `predicate` is true
+#[must_use = "iterator adaptors are lazy and do nothing unless consumed"]
 pub struct SkipWhile<'a, A, T> {
     iter: T,
     flag: bool,
@@ -1517,6 +1528,7 @@ impl<'a, A, T: Iterator<A>> Iterator<A> for SkipWhile<'a, A, T> {
 }
 
 /// An iterator which only accepts elements while `predicate` is true
+#[must_use = "iterator adaptors are lazy and do nothing unless consumed"]
 pub struct TakeWhile<'a, A, T> {
     iter: T,
     flag: bool,
@@ -1552,6 +1564,7 @@ impl<'a, A, T: Iterator<A>> Iterator<A> for TakeWhile<'a, A, T> {
 
 /// An iterator which skips over `n` elements of `iter`.
 #[deriving(Clone)]
+#[must_use = "iterator adaptors are lazy and do nothing unless consumed"]
 pub struct Skip<T> {
     iter: T,
     n: uint
@@ -1616,6 +1629,7 @@ impl<A, T: RandomAccessIterator<A>> RandomAccessIterator<A> for Skip<T> {
 
 /// An iterator which only iterates over the first `n` iterations of `iter`.
 #[deriving(Clone)]
+#[must_use = "iterator adaptors are lazy and do nothing unless consumed"]
 pub struct Take<T> {
     iter: T,
     n: uint
@@ -1665,6 +1679,7 @@ impl<A, T: RandomAccessIterator<A>> RandomAccessIterator<A> for Take<T> {
 
 
 /// An iterator to maintain state while iterating another iterator
+#[must_use = "iterator adaptors are lazy and do nothing unless consumed"]
 pub struct Scan<'a, A, B, T, St> {
     iter: T,
     f: |&mut St, A|: 'a -> Option<B>,
@@ -1689,6 +1704,7 @@ impl<'a, A, B, T: Iterator<A>, St> Iterator<B> for Scan<'a, A, B, T, St> {
 /// An iterator that maps each element to an iterator,
 /// and yields the elements of the produced iterators
 ///
+#[must_use = "iterator adaptors are lazy and do nothing unless consumed"]
 pub struct FlatMap<'a, A, T, U> {
     iter: T,
     f: |A|: 'a -> U,
@@ -1748,6 +1764,7 @@ impl<'a,
 /// An iterator that yields `None` forever after the underlying iterator
 /// yields `None` once.
 #[deriving(Clone)]
+#[must_use = "iterator adaptors are lazy and do nothing unless consumed"]
 pub struct Fuse<T> {
     iter: T,
     done: bool
@@ -1820,6 +1837,7 @@ impl<T> Fuse<T> {
 
 /// An iterator that calls a function with a reference to each
 /// element before yielding it.
+#[must_use = "iterator adaptors are lazy and do nothing unless consumed"]
 pub struct Inspect<'a, A, T> {
     iter: T,
     f: |&A|: 'a
@@ -2299,4 +2317,3 @@ pub mod order {
         }
     }
 }
-

branches/snap-stage3/src/librustc/lint/builtin.rs

@@ -669,22 +669,13 @@ impl LintPass for UnusedResult {
                 if ast_util::is_local(did) {
                     match cx.tcx.map.get(did.node) {
                         ast_map::NodeItem(it) => {
-                            if attr::contains_name(it.attrs.as_slice(),
-                                                   "must_use") {
-                                cx.span_lint(UNUSED_MUST_USE, s.span,
-                                             "unused result which must be used");
-                                warned = true;
-                            }
+                            warned |= check_must_use(cx, it.attrs.as_slice(), s.span);
                         }
                         _ => {}
                     }
                 } else {
                     csearch::get_item_attrs(&cx.sess().cstore, did, |attrs| {
-                        if attr::contains_name(attrs.as_slice(), "must_use") {
-                            cx.span_lint(UNUSED_MUST_USE, s.span,
-                                         "unused result which must be used");
-                            warned = true;
-                        }
+                        warned |= check_must_use(cx, attrs.as_slice(), s.span);
                     });
                 }
             }
@@ -693,6 +684,25 @@ impl LintPass for UnusedResult {
         if !warned {
             cx.span_lint(UNUSED_RESULT, s.span, "unused result");
         }
+
+        fn check_must_use(cx: &Context, attrs: &[ast::Attribute], sp: Span) -> bool {
+            for attr in attrs.iter() {
+                if attr.check_name("must_use") {
+                    let mut msg = "unused result which must be used".to_string();
+                    // check for #[must_use="..."]
+                    match attr.value_str() {
+                        None => {}
+                        Some(s) => {
+                            msg.push_str(": ");
+                            msg.push_str(s.get());
+                        }
+                    }
+                    cx.span_lint(UNUSED_MUST_USE, sp, msg.as_slice());
+                    return true;
+                }
+            }
+            false
+        }
     }
 }
 

branches/snap-stage3/src/librustc/middle/trans/base.rs

@@ -862,9 +862,12 @@ pub fn trans_external_path(ccx: &CrateContext, did: ast::DefId, t: ty::t) -> Val
         ty::ty_bare_fn(ref fn_ty) => {
             match fn_ty.abi.for_target(ccx.sess().targ_cfg.os,
                                        ccx.sess().targ_cfg.arch) {
-                Some(Rust) | Some(RustIntrinsic) => {
+                Some(Rust) => {
                     get_extern_rust_fn(ccx, t, name.as_slice(), did)
                 }
+                Some(RustIntrinsic) => {
+                    ccx.sess().bug("unexpected intrinsic in trans_external_path")
+                }
                 Some(..) | None => {
                     foreign::register_foreign_item_fn(ccx, fn_ty.abi, t,
                                                       name.as_slice(), None)
@@ -1781,9 +1784,9 @@ fn register_fn(ccx: &CrateContext,
                -> ValueRef {
     match ty::get(node_type).sty {
         ty::ty_bare_fn(ref f) => {
-            assert!(f.abi == Rust || f.abi == RustIntrinsic);
+            assert!(f.abi == Rust);
         }
-        _ => fail!("expected bare rust fn or an intrinsic")
+        _ => fail!("expected bare rust fn")
     };
 
     let llfn = decl_rust_fn(ccx, node_type, sym.as_slice());

branches/snap-stage3/src/librustc/middle/trans/callee.rs

@@ -19,7 +19,6 @@
 use arena::TypedArena;
 use back::abi;
 use back::link;
-use driver::session;
 use lib::llvm::ValueRef;
 use lib::llvm::llvm;
 use metadata::csearch;
@@ -40,6 +39,7 @@ use middle::trans::expr;
 use middle::trans::glue;
 use middle::trans::inline;
 use middle::trans::foreign;
+use middle::trans::intrinsic;
 use middle::trans::meth;
 use middle::trans::monomorphize;
 use middle::trans::type_::Type;
@@ -53,7 +53,6 @@ use util::ppaux::Repr;
 use std::gc::Gc;
 use syntax::ast;
 use synabi = syntax::abi;
-use syntax::ast_map;
 
 pub struct MethodData {
     pub llfn: ValueRef,
@@ -68,6 +67,8 @@ pub enum CalleeData {
     // value (which is a pair).
     Fn(/* llfn */ ValueRef),
 
+    Intrinsic(ast::NodeId, subst::Substs),
+
     TraitMethod(MethodData)
 }
 
@@ -119,7 +120,21 @@ fn trans<'a>(bcx: &'a Block<'a>, expr: &ast::Expr) -> Callee<'a> {
 
     fn trans_def<'a>(bcx: &'a Block<'a>, def: def::Def, ref_expr: &ast::Expr)
                  -> Callee<'a> {
+        debug!("trans_def(def={}, ref_expr={})", def.repr(bcx.tcx()), ref_expr.repr(bcx.tcx()));
+        let expr_ty = node_id_type(bcx, ref_expr.id);
         match def {
+            def::DefFn(did, _) if match ty::get(expr_ty).sty {
+                ty::ty_bare_fn(ref f) => f.abi == synabi::RustIntrinsic,
+                _ => false
+            } => {
+                let substs = node_id_substs(bcx, ExprId(ref_expr.id));
+                let def_id = if did.krate != ast::LOCAL_CRATE {
+                    inline::maybe_instantiate_inline(bcx.ccx(), did)
+                } else {
+                    did
+                };
+                Callee { bcx: bcx, data: Intrinsic(def_id.node, substs) }
+            }
             def::DefFn(did, _) |
             def::DefStaticMethod(did, def::FromImpl(_), _) => {
                 fn_callee(bcx, trans_fn_ref(bcx, did, ExprId(ref_expr.id)))
@@ -460,27 +475,8 @@ pub fn trans_fn_ref_with_vtables(
         }
     };
 
-    // We must monomorphise if the fn has type parameters, is a rust
-    // intrinsic, or is a default method.  In particular, if we see an
-    // intrinsic that is inlined from a different crate, we want to reemit the
-    // intrinsic instead of trying to call it in the other crate.
-    let must_monomorphise = if !substs.types.is_empty() || is_default {
-        true
-    } else if def_id.krate == ast::LOCAL_CRATE {
-        let map_node = session::expect(
-            ccx.sess(),
-            tcx.map.find(def_id.node),
-            || "local item should be in ast map".to_string());
-
-        match map_node {
-            ast_map::NodeForeignItem(_) => {
-                tcx.map.get_foreign_abi(def_id.node) == synabi::RustIntrinsic
-            }
-            _ => false
-        }
-    } else {
-        false
-    };
+    // We must monomorphise if the fn has type parameters or is a default method.
+    let must_monomorphise = !substs.types.is_empty() || is_default;
 
     // Create a monomorphic version of generic functions
     if must_monomorphise {
@@ -662,6 +658,12 @@ pub fn trans_call_inner<'a>(
     let callee = get_callee(bcx, cleanup::CustomScope(arg_cleanup_scope));
     let mut bcx = callee.bcx;
 
+    let (abi, ret_ty) = match ty::get(callee_ty).sty {
+        ty::ty_bare_fn(ref f) => (f.abi, f.sig.output),
+        ty::ty_closure(ref f) => (synabi::Rust, f.sig.output),
+        _ => fail!("expected bare rust fn or closure in trans_call_inner")
+    };
+
     let (llfn, llenv, llself) = match callee.data {
         Fn(llfn) => {
             (llfn, None, None)
@@ -679,14 +681,19 @@ pub fn trans_call_inner<'a>(
             let llenv = Load(bcx, llenv);
             (llfn, Some(llenv), None)
         }
-    };
+        Intrinsic(node, substs) => {
+            assert!(abi == synabi::RustIntrinsic);
+            assert!(dest.is_some());
 
-    let (abi, ret_ty) = match ty::get(callee_ty).sty {
-        ty::ty_bare_fn(ref f) => (f.abi, f.sig.output),
-        ty::ty_closure(ref f) => (synabi::Rust, f.sig.output),
-        _ => fail!("expected bare rust fn or closure in trans_call_inner")
+            return intrinsic::trans_intrinsic_call(bcx, node, callee_ty,
+                                                   arg_cleanup_scope, args,
+                                                   dest.unwrap(), substs);
+        }
     };
-    let is_rust_fn = abi == synabi::Rust || abi == synabi::RustIntrinsic;
+
+    // Intrinsics should not become actual functions.
+    // We trans them in place in `trans_intrinsic_call`
+    assert!(abi != synabi::RustIntrinsic);
 
     // Generate a location to store the result. If the user does
     // not care about the result, just make a stack slot.
@@ -716,7 +723,7 @@ pub fn trans_call_inner<'a>(
     // and done, either the return value of the function will have been
     // written in opt_llretslot (if it is Some) or `llresult` will be
     // set appropriately (otherwise).
-    if is_rust_fn {
+    if abi == synabi::Rust {
         let mut llargs = Vec::new();
 
         // Push the out-pointer if we use an out-pointer for this
@@ -816,13 +823,13 @@ pub enum CallArgs<'a> {
     ArgOverloadedOp(Datum<Expr>, Option<(Datum<Expr>, ast::NodeId)>),
 }
 
-fn trans_args<'a>(cx: &'a Block<'a>,
-                  args: CallArgs,
-                  fn_ty: ty::t,
-                  llargs: &mut Vec<ValueRef> ,
-                  arg_cleanup_scope: cleanup::ScopeId,
-                  ignore_self: bool)
-                  -> &'a Block<'a> {
+pub fn trans_args<'a>(cx: &'a Block<'a>,
+                      args: CallArgs,
+                      fn_ty: ty::t,
+                      llargs: &mut Vec<ValueRef> ,
+                      arg_cleanup_scope: cleanup::ScopeId,
+                      ignore_self: bool)
+                      -> &'a Block<'a> {
     let _icx = push_ctxt("trans_args");
     let arg_tys = ty::ty_fn_args(fn_ty);
     let variadic = ty::fn_is_variadic(fn_ty);

branches/snap-stage3/src/librustc/middle/trans/foreign.rs

@@ -76,7 +76,7 @@ pub fn llvm_calling_convention(ccx: &CrateContext,
     abi.for_target(os, arch).map(|abi| {
         match abi {
             RustIntrinsic => {
-                // Intrinsics are emitted by monomorphic fn
+                // Intrinsics are emitted at the call site
                 ccx.sess().bug("asked to register intrinsic fn");
             }