Auto merge of #23337 - Manishearth:rollup, r=Manishearth

r? @Manishearth

Author: bors

mk/llvm.mk

@@ -44,10 +44,10 @@ $$(LLVM_STAMP_$(1)): $(S)src/rustllvm/llvm-auto-clean-trigger
 	touch -r $$@.start_time $$@ && rm $$@.start_time
 
 ifeq ($$(CFG_ENABLE_LLVM_STATIC_STDCPP),1)
-LLVM_STDCPP_LOCATION_$(1) = $$(shell $$(CC_$(1)) $$(CFG_GCCISH_CFLAGS_$(1)) \
-					-print-file-name=libstdc++.a)
+LLVM_STDCPP_RUSTFLAGS_$(1) = -L "$$(dir $$(shell $$(CC_$(1)) $$(CFG_GCCISH_CFLAGS_$(1)) \
+					-print-file-name=libstdc++.a))"
 else
-LLVM_STDCPP_LOCATION_$(1) =
+LLVM_STDCPP_RUSTFLAGS_$(1) =
 endif
 
 

mk/main.mk

@@ -30,8 +30,8 @@ CFG_PACKAGE_VERS=$(CFG_RELEASE_NUM)
 CFG_DISABLE_UNSTABLE_FEATURES=1
 endif
 ifeq ($(CFG_RELEASE_CHANNEL),beta)
-CFG_RELEASE=$(CFG_RELEASE_NUM)-beta(CFG_PRERELEASE_VERSION)
-CFG_PACKAGE_VERS=$(CFG_RELEASE_NUM)-beta(CFG_PRERELEASE_VERSION)
+CFG_RELEASE=$(CFG_RELEASE_NUM)-beta$(CFG_PRERELEASE_VERSION)
+CFG_PACKAGE_VERS=$(CFG_RELEASE_NUM)-beta$(CFG_PRERELEASE_VERSION)
 CFG_DISABLE_UNSTABLE_FEATURES=1
 endif
 ifeq ($(CFG_RELEASE_CHANNEL),nightly)

mk/target.mk

@@ -85,7 +85,7 @@ $$(TLIB$(1)_T_$(2)_H_$(3))/stamp.$(4): \
 		$$(RUST_LIB_FLAGS_ST$(1)) \
 		-L "$$(RT_OUTPUT_DIR_$(2))" \
 		-L "$$(LLVM_LIBDIR_$(2))" \
-		-L "$$(dir $$(LLVM_STDCPP_LOCATION_$(2)))" \
+		$$(LLVM_STDCPP_RUSTFLAGS_$(2)) \
 		$$(RUSTFLAGS_$(4)) \
 		--out-dir $$(@D) \
 		-C extra-filename=-$$(CFG_FILENAME_EXTRA) \

src/doc/trpl/hello-cargo.md

@@ -85,9 +85,11 @@ Hello, world!
 Bam! We build our project with `cargo build`, and run it with
 `./target/debug/hello_world`. This hasn't bought us a whole lot over our simple use
 of `rustc`, but think about the future: when our project has more than one
-file, we would need to call `rustc` more than once, and pass it a bunch of options to
+file, we would need to call `rustc` more than once and pass it a bunch of options to
 tell it to build everything together. With Cargo, as our project grows, we can
-just `cargo build` and it'll work the right way. When you're project is finally ready for release, you can use `cargo build --release` to compile your crates with optimizations.
+just `cargo build`, and it'll work the right way. When your project is finally
+ready for release, you can use `cargo build --release` to compile your crates with
+optimizations.
 
 You'll also notice that Cargo has created a new file: `Cargo.lock`.
 

src/etc/gdb_rust_pretty_printing.py

@@ -27,9 +27,18 @@ def rust_pretty_printer_lookup_function(val):
     if type_code == gdb.TYPE_CODE_STRUCT:
         struct_kind = classify_struct(val.type)
 
+        if struct_kind == STRUCT_KIND_SLICE:
+            return RustSlicePrinter(val)
+
         if struct_kind == STRUCT_KIND_STR_SLICE:
             return RustStringSlicePrinter(val)
 
+        if struct_kind == STRUCT_KIND_STD_VEC:
+            return RustStdVecPrinter(val)
+
+        if struct_kind == STRUCT_KIND_STD_STRING:
+            return RustStdStringPrinter(val)
+
         if struct_kind == STRUCT_KIND_TUPLE:
             return RustTuplePrinter(val)
 
@@ -172,6 +181,28 @@ def children(self):
     def display_hint(self):
         return "array"
 
+class RustSlicePrinter:
+    def __init__(self, val):
+        self.val = val
+
+    def display_hint(self):
+        return "array"
+
+    def to_string(self):
+        length = int(self.val["length"])
+        return self.val.type.tag + ("(len: %i)" % length)
+
+    def children(self):
+        cs = []
+        length = int(self.val["length"])
+        data_ptr = self.val["data_ptr"]
+        assert data_ptr.type.code == gdb.TYPE_CODE_PTR
+        pointee_type = data_ptr.type.target()
+
+        for index in range(0, length):
+            cs.append((str(index), (data_ptr + index).dereference()))
+
+        return cs
 
 class RustStringSlicePrinter:
     def __init__(self, val):
@@ -181,6 +212,35 @@ def to_string(self):
         slice_byte_len = self.val["length"]
         return '"%s"' % self.val["data_ptr"].string(encoding="utf-8", length=slice_byte_len)
 
+class RustStdVecPrinter:
+    def __init__(self, val):
+        self.val = val
+
+    def display_hint(self):
+        return "array"
+
+    def to_string(self):
+        length = int(self.val["len"])
+        cap = int(self.val["cap"])
+        return self.val.type.tag + ("(len: %i, cap: %i)" % (length, cap))
+
+    def children(self):
+        cs = []
+        (length, data_ptr) = extract_length_and_data_ptr_from_std_vec(self.val)
+        pointee_type = data_ptr.type.target()
+
+        for index in range(0, length):
+            cs.append((str(index), (data_ptr + index).dereference()))
+        return cs
+
+class RustStdStringPrinter:
+    def __init__(self, val):
+        self.val = val
+
+    def to_string(self):
+        (length, data_ptr) = extract_length_and_data_ptr_from_std_vec(self.val["vec"])
+        return '"%s"' % data_ptr.string(encoding="utf-8", length=length)
+
 
 class RustCStyleEnumPrinter:
     def __init__(self, val):
@@ -204,19 +264,38 @@ def to_string(self):
 STRUCT_KIND_TUPLE_VARIANT   = 3
 STRUCT_KIND_STRUCT_VARIANT  = 4
 STRUCT_KIND_CSTYLE_VARIANT  = 5
-STRUCT_KIND_STR_SLICE       = 6
+STRUCT_KIND_SLICE           = 6
+STRUCT_KIND_STR_SLICE       = 7
+STRUCT_KIND_STD_VEC         = 8
+STRUCT_KIND_STD_STRING      = 9
 
 
 def classify_struct(type):
+    # print("\nclassify_struct: tag=%s\n" % type.tag)
     if type.tag == "&str":
         return STRUCT_KIND_STR_SLICE
 
+    if type.tag.startswith("&[") and type.tag.endswith("]"):
+        return STRUCT_KIND_SLICE
+
     fields = list(type.fields())
     field_count = len(fields)
 
     if field_count == 0:
         return STRUCT_KIND_REGULAR_STRUCT
 
+    if (field_count == 3 and
+        fields[0].name == "ptr" and
+        fields[1].name == "len" and
+        fields[2].name == "cap" and
+        type.tag.startswith("Vec<")):
+        return STRUCT_KIND_STD_VEC
+
+    if (field_count == 1 and
+        fields[0].name == "vec" and
+        type.tag == "String"):
+        return STRUCT_KIND_STD_STRING
+
     if fields[0].name == "RUST$ENUM$DISR":
         if field_count == 1:
             return STRUCT_KIND_CSTYLE_VARIANT
@@ -254,3 +333,11 @@ def get_field_at_index(val, index):
             return field
         i += 1
     return None
+
+def extract_length_and_data_ptr_from_std_vec(vec_val):
+    length = int(vec_val["len"])
+    vec_ptr_val = vec_val["ptr"]
+    unique_ptr_val = vec_ptr_val[first_field(vec_ptr_val)]
+    data_ptr = unique_ptr_val[first_field(unique_ptr_val)]
+    assert data_ptr.type.code == gdb.TYPE_CODE_PTR
+    return (length, data_ptr)

src/liballoc/heap.rs

@@ -198,6 +198,7 @@ mod imp {
     extern {}
 
     extern {
+        #[allocator]
         fn je_mallocx(size: size_t, flags: c_int) -> *mut c_void;
         fn je_rallocx(ptr: *mut c_void, size: size_t, flags: c_int) -> *mut c_void;
         fn je_xallocx(ptr: *mut c_void, size: size_t, extra: size_t, flags: c_int) -> size_t;

src/liballoc/lib.rs

@@ -69,6 +69,7 @@
 
 #![feature(no_std)]
 #![no_std]
+#![feature(allocator)]
 #![feature(lang_items, unsafe_destructor)]
 #![feature(box_syntax)]
 #![feature(optin_builtin_traits)]

src/libcore/hash/mod.rs

@@ -70,9 +70,7 @@ mod sip;
 /// A hashable type.
 ///
 /// The `H` type parameter is an abstract hash state that is used by the `Hash`
-/// to compute the hash. Specific implementations of this trait may specialize
-/// for particular instances of `H` in order to be able to optimize the hashing
-/// behavior.
+/// to compute the hash.
 #[stable(feature = "rust1", since = "1.0.0")]
 pub trait Hash {
     /// Feeds this value into the state given, updating the hasher as necessary.

src/libcore/ptr.rs

@@ -33,31 +33,34 @@
 //! let my_speed_ptr: *mut i32 = &mut my_speed;
 //! ```
 //!
+//! To get a pointer to a boxed value, dereference the box:
+//!
+//! ```
+//! let my_num: Box<i32> = Box::new(10);
+//! let my_num_ptr: *const i32 = &*my_num;
+//! let mut my_speed: Box<i32> = Box::new(88);
+//! let my_speed_ptr: *mut i32 = &mut *my_speed;
+//! ```
+//!
 //! This does not take ownership of the original allocation
 //! and requires no resource management later,
 //! but you must not use the pointer after its lifetime.
 //!
-//! ## 2. Transmute an owned box (`Box<T>`).
+//! ## 2. Consume a box (`Box<T>`).
 //!
-//! The `transmute` function takes, by value, whatever it's given
-//! and returns it as whatever type is requested, as long as the
-//! types are the same size. Because `Box<T>` and `*mut T` have the same
-//! representation they can be trivially,
-//! though unsafely, transformed from one type to the other.
+//! The `into_raw` function consumes a box and returns
+//! the raw pointer. It doesn't destroy `T` or deallocate any memory.
 //!
 //! ```
-//! use std::mem;
+//! use std::boxed;
 //!
 //! unsafe {
-//!     let my_num: Box<i32> = Box::new(10);
-//!     let my_num: *const i32 = mem::transmute(my_num);
 //!     let my_speed: Box<i32> = Box::new(88);
-//!     let my_speed: *mut i32 = mem::transmute(my_speed);
+//!     let my_speed: *mut i32 = boxed::into_raw(my_speed);
 //!
 //!     // By taking ownership of the original `Box<T>` though
-//!     // we are obligated to transmute it back later to be destroyed.
-//!     drop(mem::transmute::<_, Box<i32>>(my_speed));
-//!     drop(mem::transmute::<_, Box<i32>>(my_num));
+//!     // we are obligated to put it together later to be destroyed.
+//!     drop(Box::from_raw(my_speed));
 //! }
 //! ```
 //!

src/librustc/metadata/csearch.rs

@@ -411,3 +411,8 @@ pub fn is_defaulted_trait(cstore: &cstore::CStore, trait_def_id: ast::DefId) ->
     let cdata = cstore.get_crate_data(trait_def_id.krate);
     decoder::is_defaulted_trait(&*cdata, trait_def_id.node)
 }
+
+pub fn is_default_impl(cstore: &cstore::CStore, impl_did: ast::DefId) -> bool {
+    let cdata = cstore.get_crate_data(impl_did.krate);
+    decoder::is_default_impl(&*cdata, impl_did.node)
+}

src/librustc/metadata/decoder.rs

@@ -1537,13 +1537,18 @@ pub fn is_associated_type(cdata: Cmd, id: ast::NodeId) -> bool {
     }
 }
 
-pub fn is_defaulted_trait<'tcx>(cdata: Cmd, trait_id: ast::NodeId) -> bool {
+pub fn is_defaulted_trait(cdata: Cmd, trait_id: ast::NodeId) -> bool {
     let trait_doc = lookup_item(trait_id, cdata.data());
     assert!(item_family(trait_doc) == Family::Trait);
     let defaulted_doc = reader::get_doc(trait_doc, tag_defaulted_trait);
     reader::doc_as_u8(defaulted_doc) != 0
 }
 
+pub fn is_default_impl(cdata: Cmd, impl_id: ast::NodeId) -> bool {
+    let impl_doc = lookup_item(impl_id, cdata.data());
+    item_family(impl_doc) == Family::DefaultImpl
+}
+
 pub fn get_imported_filemaps(metadata: &[u8]) -> Vec<codemap::FileMap> {
     let crate_doc = rbml::Doc::new(metadata);
     let cm_doc = reader::get_doc(crate_doc, tag_codemap);

src/librustc/middle/dead.rs

@@ -47,6 +47,7 @@ struct MarkSymbolVisitor<'a, 'tcx: 'a> {
     struct_has_extern_repr: bool,
     ignore_non_const_paths: bool,
     inherited_pub_visibility: bool,
+    ignore_variant_stack: Vec<ast::NodeId>,
 }
 
 impl<'a, 'tcx> MarkSymbolVisitor<'a, 'tcx> {
@@ -59,6 +60,7 @@ impl<'a, 'tcx> MarkSymbolVisitor<'a, 'tcx> {
             struct_has_extern_repr: false,
             ignore_non_const_paths: false,
             inherited_pub_visibility: false,
+            ignore_variant_stack: vec![],
         }
     }
 
@@ -79,7 +81,9 @@ impl<'a, 'tcx> MarkSymbolVisitor<'a, 'tcx> {
                 def::DefPrimTy(_) => (),
                 def::DefVariant(enum_id, variant_id, _) => {
                     self.check_def_id(enum_id);
-                    self.check_def_id(variant_id);
+                    if !self.ignore_variant_stack.contains(&variant_id.node) {
+                        self.check_def_id(variant_id);
+                    }
                 }
                 _ => {
                     self.check_def_id(def.def_id());
@@ -278,6 +282,23 @@ impl<'a, 'tcx, 'v> Visitor<'v> for MarkSymbolVisitor<'a, 'tcx> {
         visit::walk_expr(self, expr);
     }
 
+    fn visit_arm(&mut self, arm: &ast::Arm) {
+        if arm.pats.len() == 1 {
+            let pat = &*arm.pats[0];
+            let variants = pat_util::necessary_variants(&self.tcx.def_map, pat);
+
+            // Inside the body, ignore constructions of variants
+            // necessary for the pattern to match. Those construction sites
+            // can't be reached unless the variant is constructed elsewhere.
+            let len = self.ignore_variant_stack.len();
+            self.ignore_variant_stack.push_all(&*variants);
+            visit::walk_arm(self, arm);
+            self.ignore_variant_stack.truncate(len);
+        } else {
+            visit::walk_arm(self, arm);
+        }
+    }
+
     fn visit_pat(&mut self, pat: &ast::Pat) {
         let def_map = &self.tcx.def_map;
         match pat.node {
@@ -397,6 +418,11 @@ fn create_and_seed_worklist(tcx: &ty::ctxt,
         worklist.push(*id);
     }
     for id in reachable_symbols {
+        // Reachable variants can be dead, because we warn about
+        // variants never constructed, not variants never used.
+        if let Some(ast_map::NodeVariant(..)) = tcx.map.find(*id) {
+            continue;
+        }
         worklist.push(*id);
     }
 

src/librustc/middle/pat_util.rs

@@ -155,3 +155,27 @@ pub fn def_to_path(tcx: &ty::ctxt, id: ast::DefId) -> ast::Path {
         span: DUMMY_SP,
     })
 }
+
+/// Return variants that are necessary to exist for the pattern to match.
+pub fn necessary_variants(dm: &DefMap, pat: &ast::Pat) -> Vec<ast::NodeId> {
+    let mut variants = vec![];
+    walk_pat(pat, |p| {
+        match p.node {
+            ast::PatEnum(_, _) |
+            ast::PatIdent(_, _, None) |
+            ast::PatStruct(..) => {
+                match dm.borrow().get(&p.id) {
+                    Some(&PathResolution {base_def: DefVariant(_, id, _), ..}) => {
+                        variants.push(id.node);
+                    }
+                    _ => ()
+                }
+            }
+            _ => ()
+        }
+        true
+    });
+    variants.sort();
+    variants.dedup();
+    variants
+}