Auto merge of #30043 - arielb1:split-metadata, r=nikomatsakis

This improves bootstrap times because of better parallelism - though I need to measure how much - and allows metadata to be modified without triggering a full recompile. This also ensures that metadata handling and the rest of rustc remain decoupled, which is a first step for switching to a new metadata format.

This is a [breaking-change] to all plugin authors because of the following renames:
 * `rustc::plugin` is now `rustc_plugin`
 * `rustc::metadata` is now `rustc_metadata`
 * Most data types from `rustc::metadata`, along with `LOCAL_CRATE`, are now in `rustc::middle::cstore`.
 * The CStore methods were split between the `rustc::middle::CrateStore` trait (and trait object) and the `rustc_metadata::cstore::CStore`, with an `Rc<CrateStore>` stored in the `Session`. The inner `CStore` can be accessed via the inner `Any` bound, but this is deprecated.

r? @nikomatsakis

mk/crates.mk

@@ -56,7 +56,8 @@ TARGET_CRATES := libc std flate arena term \
 		 alloc_system
 RUSTC_CRATES := rustc rustc_typeck rustc_mir rustc_borrowck rustc_resolve rustc_driver \
                 rustc_trans rustc_back rustc_llvm rustc_privacy rustc_lint \
-                rustc_data_structures rustc_front rustc_platform_intrinsics
+                rustc_data_structures rustc_front rustc_platform_intrinsics \
+                rustc_plugin rustc_metadata
 HOST_CRATES := syntax $(RUSTC_CRATES) rustdoc fmt_macros
 TOOLS := compiletest rustdoc rustc rustbook error-index-generator
 
@@ -87,21 +88,23 @@ DEPS_test := std getopts serialize rbml term native:rust_test_helpers
 
 DEPS_syntax := std term serialize log fmt_macros arena libc rustc_bitflags
 
-DEPS_rustc := syntax flate arena serialize getopts rbml rustc_front\
+DEPS_rustc := syntax flate arena serialize getopts rustc_front\
               log graphviz rustc_llvm rustc_back rustc_data_structures
 DEPS_rustc_back := std syntax rustc_llvm rustc_front flate log libc
 DEPS_rustc_borrowck := rustc rustc_front log graphviz syntax
 DEPS_rustc_data_structures := std log serialize
 DEPS_rustc_driver := arena flate getopts graphviz libc rustc rustc_back rustc_borrowck \
                      rustc_typeck rustc_mir rustc_resolve log syntax serialize rustc_llvm \
-		             rustc_trans rustc_privacy rustc_lint rustc_front
-
+	             rustc_trans rustc_privacy rustc_lint rustc_front rustc_plugin \
+                     rustc_metadata
 DEPS_rustc_front := std syntax log serialize
 DEPS_rustc_lint := rustc log syntax
 DEPS_rustc_llvm := native:rustllvm libc std rustc_bitflags
+DEPS_rustc_metadata := rustc rustc_front syntax rbml
 DEPS_rustc_mir := rustc rustc_front syntax
 DEPS_rustc_resolve := rustc rustc_front log syntax
 DEPS_rustc_platform_intrinsics := rustc rustc_llvm
+DEPS_rustc_plugin := rustc rustc_metadata syntax
 DEPS_rustc_privacy := rustc rustc_front log syntax
 DEPS_rustc_trans := arena flate getopts graphviz libc rustc rustc_back rustc_mir \
                     log syntax serialize rustc_llvm rustc_front rustc_platform_intrinsics

src/doc/book/compiler-plugins.md

@@ -8,12 +8,12 @@ extend the compiler's behavior with new syntax extensions, lint checks, etc.
 A plugin is a dynamic library crate with a designated *registrar* function that
 registers extensions with `rustc`. Other crates can load these extensions using
 the crate attribute `#![plugin(...)]`.  See the
-[`rustc::plugin`](../rustc/plugin/index.html) documentation for more about the
+[`rustc_plugin`](../rustc_plugin/index.html) documentation for more about the
 mechanics of defining and loading a plugin.
 
 If present, arguments passed as `#![plugin(foo(... args ...))]` are not
 interpreted by rustc itself.  They are provided to the plugin through the
-`Registry`'s [`args` method](../rustc/plugin/registry/struct.Registry.html#method.args).
+`Registry`'s [`args` method](../rustc_plugin/registry/struct.Registry.html#method.args).
 
 In the vast majority of cases, a plugin should *only* be used through
 `#![plugin]` and not through an `extern crate` item.  Linking a plugin would
@@ -43,13 +43,14 @@ that implements Roman numeral integer literals.
 
 extern crate syntax;
 extern crate rustc;
+extern crate rustc_plugin;
 
 use syntax::codemap::Span;
 use syntax::parse::token;
 use syntax::ast::TokenTree;
 use syntax::ext::base::{ExtCtxt, MacResult, DummyResult, MacEager};
 use syntax::ext::build::AstBuilder;  // trait for expr_usize
-use rustc::plugin::Registry;
+use rustc_plugin::Registry;
 
 fn expand_rn(cx: &mut ExtCtxt, sp: Span, args: &[TokenTree])
         -> Box<MacResult + 'static> {
@@ -120,7 +121,7 @@ The advantages over a simple `fn(&str) -> u32` are:
 In addition to procedural macros, you can define new
 [`derive`](../reference.html#derive)-like attributes and other kinds of
 extensions.  See
-[`Registry::register_syntax_extension`](../rustc/plugin/registry/struct.Registry.html#method.register_syntax_extension)
+[`Registry::register_syntax_extension`](../rustc_plugin/registry/struct.Registry.html#method.register_syntax_extension)
 and the [`SyntaxExtension`
 enum](https://doc.rust-lang.org/syntax/ext/base/enum.SyntaxExtension.html).  For
 a more involved macro example, see
@@ -189,10 +190,11 @@ extern crate syntax;
 // Load rustc as a plugin to get macros
 #[macro_use]
 extern crate rustc;
+extern crate rustc_plugin;
 
 use rustc::lint::{EarlyContext, LintContext, LintPass, EarlyLintPass,
                   EarlyLintPassObject, LintArray};
-use rustc::plugin::Registry;
+use rustc_plugin::Registry;
 use syntax::ast;
 
 declare_lint!(TEST_LINT, Warn, "Warn about items named 'lintme'");

src/doc/complement-lang-faq.md

@@ -158,7 +158,7 @@ can be combined to control the exact logging you want to see. For example, when
 debugging linking in the compiler, you might set the following:
 
 ```sh
-RUST_LOG=rustc::metadata::creader,rustc::util::filesearch,rustc::back::rpath
+RUST_LOG=rustc_metadata::creader,rustc::util::filesearch,rustc::back::rpath
 ```
 
 For a full description, see [the logging crate][1].

src/grammar/verify.rs

@@ -25,7 +25,9 @@ use std::path::Path;
 use syntax::parse;
 use syntax::parse::lexer;
 use rustc::session::{self, config};
+use rustc::middle::cstore::DummyCrateStore;
 
+use std::rc::Rc;
 use syntax::ast;
 use syntax::ast::Name;
 use syntax::codemap;
@@ -286,7 +288,8 @@ fn main() {
 
     let options = config::basic_options();
     let session = session::build_session(options, None,
-                                         syntax::diagnostics::registry::Registry::new(&[]));
+                                         syntax::diagnostics::registry::Registry::new(&[]),
+                                         Rc::new(DummyCrateStore));
     let filemap = session.parse_sess.codemap().new_filemap(String::from("<n/a>"), code);
     let mut lexer = lexer::StringReader::new(session.diagnostic(), filemap);
     let cm = session.codemap();

src/librustc/diagnostics.rs

@@ -1899,51 +1899,6 @@ contain references (with a maximum lifetime of `'a`).
 [1]: https://github.com/rust-lang/rfcs/pull/1156
 "##,
 
-E0454: r##"
-A link name was given with an empty name. Erroneous code example:
-
-```
-#[link(name = "")] extern {} // error: #[link(name = "")] given with empty name
-```
-
-The rust compiler cannot link to an external library if you don't give it its
-name. Example:
-
-```
-#[link(name = "some_lib")] extern {} // ok!
-```
-"##,
-
-E0458: r##"
-An unknown "kind" was specified for a link attribute. Erroneous code example:
-
-```
-#[link(kind = "wonderful_unicorn")] extern {}
-// error: unknown kind: `wonderful_unicorn`
-```
-
-Please specify a valid "kind" value, from one of the following:
- * static
- * dylib
- * framework
-"##,
-
-E0459: r##"
-A link was used without a name parameter. Erroneous code example:
-
-```
-#[link(kind = "dylib")] extern {}
-// error: #[link(...)] specified without `name = "foo"`
-```
-
-Please add the name parameter to allow the rust compiler to find the library
-you want. Example:
-
-```
-#[link(kind = "dylib", name = "some_lib")] extern {} // ok!
-```
-"##,
-
 E0493: r##"
 A type with a destructor was assigned to an invalid type of variable. Erroneous
 code example:
@@ -2144,20 +2099,6 @@ register_diagnostics! {
     E0400, // overloaded derefs are not allowed in constants
     E0452, // malformed lint attribute
     E0453, // overruled by outer forbid
-    E0455, // native frameworks are only available on OSX targets
-    E0456, // plugin `..` is not available for triple `..`
-    E0457, // plugin `..` only found in rlib format, but must be available...
-    E0460, // found possibly newer version of crate `..`
-    E0461, // couldn't find crate `..` with expected target triple ..
-    E0462, // found staticlib `..` instead of rlib or dylib
-    E0463, // can't find crate for `..`
-    E0464, // multiple matching crates for `..`
-    E0465, // multiple .. candidates for `..` found
-    E0466, // bad macro import
-    E0467, // bad macro reexport
-    E0468, // an `extern crate` loading macros must be at the crate root
-    E0469, // imported macro not found
-    E0470, // reexported macro not found
     E0471, // constant evaluation error: ..
     E0472, // asm! is unsupported on this target
     E0473, // dereference of reference outside its lifetime
@@ -2181,6 +2122,4 @@ register_diagnostics! {
     E0491, // in type `..`, reference has a longer lifetime than the data it...
     E0492, // cannot borrow a constant which contains interior mutability
     E0495, // cannot infer an appropriate lifetime due to conflicting requirements
-    E0498, // malformed plugin attribute
-    E0514, // metadata version mismatch
 }

src/librustc/front/map/definitions.rs

@@ -8,7 +8,7 @@
 // option. This file may not be copied, modified, or distributed
 // except according to those terms.
 
-use metadata::cstore::LOCAL_CRATE;
+use middle::cstore::LOCAL_CRATE;
 use middle::def_id::{DefId, DefIndex};
 use rustc_data_structures::fnv::FnvHashMap;
 use rustc_front::hir;

src/librustc/front/map/mod.rs

@@ -14,8 +14,8 @@ use self::MapEntry::*;
 use self::collector::NodeCollector;
 pub use self::definitions::{Definitions, DefKey, DefPath, DefPathData, DisambiguatedDefPathData};
 
-use metadata::inline::InlinedItem;
-use metadata::inline::InlinedItem as II;
+use middle::cstore::InlinedItem;
+use middle::cstore::InlinedItem as II;
 use middle::def_id::DefId;
 
 use syntax::abi;

src/librustc/lib.rs

@@ -33,7 +33,6 @@
 #![feature(const_fn)]
 #![feature(core)]
 #![feature(duration_span)]
-#![feature(dynamic_lib)]
 #![feature(enumset)]
 #![feature(hashmap_hasher)]
 #![feature(into_cow)]
@@ -68,7 +67,6 @@ extern crate rustc_back;
 extern crate rustc_front;
 extern crate rustc_data_structures;
 extern crate serialize;
-extern crate rbml;
 extern crate collections;
 #[macro_use] extern crate log;
 #[macro_use] extern crate syntax;
@@ -100,9 +98,8 @@ pub mod front {
 }
 
 pub mod middle {
-    pub mod expr_use_visitor; // STAGE0: increase glitch immunity
     pub mod astconv_util;
-    pub mod astencode;
+    pub mod expr_use_visitor; // STAGE0: increase glitch immunity
     pub mod cfg;
     pub mod check_const;
     pub mod check_static_recursion;
@@ -111,6 +108,7 @@ pub mod middle {
     pub mod check_no_asm;
     pub mod check_rvalues;
     pub mod const_eval;
+    pub mod cstore;
     pub mod dataflow;
     pub mod dead;
     pub mod def;
@@ -138,12 +136,8 @@ pub mod middle {
     pub mod weak_lang_items;
 }
 
-pub mod metadata;
-
 pub mod session;
 
-pub mod plugin;
-
 pub mod lint;
 
 pub mod util {