Auto merge of #37681 - nrc:crate-metadata, r=@alexcrichton

add --crate-type metadata

r? @alexcrichton

src/librustc/middle/cstore.rs

@@ -56,12 +56,13 @@ pub struct LinkMeta {
     pub crate_hash: Svh,
 }
 
-// Where a crate came from on the local filesystem. One of these two options
+// Where a crate came from on the local filesystem. One of these three options
 // must be non-None.
 #[derive(PartialEq, Clone, Debug)]
 pub struct CrateSource {
     pub dylib: Option<(PathBuf, PathKind)>,
     pub rlib: Option<(PathBuf, PathKind)>,
+    pub rmeta: Option<(PathBuf, PathKind)>,
 }
 
 #[derive(RustcEncodable, RustcDecodable, Copy, Clone, Ord, PartialOrd, Eq, PartialEq, Debug)]
@@ -76,6 +77,30 @@ pub enum DepKind {
     Explicit,
 }
 
+#[derive(PartialEq, Clone, Debug)]
+pub enum LibSource {
+    Some(PathBuf),
+    MetadataOnly,
+    None,
+}
+
+impl LibSource {
+    pub fn is_some(&self) -> bool {
+        if let LibSource::Some(_) = *self {
+            true
+        } else {
+            false
+        }
+    }
+
+    pub fn option(&self) -> Option<PathBuf> {
+        match *self {
+            LibSource::Some(ref p) => Some(p.clone()),
+            LibSource::MetadataOnly | LibSource::None => None,
+        }
+    }
+}
+
 #[derive(Copy, Debug, PartialEq, Clone, RustcEncodable, RustcDecodable)]
 pub enum LinkagePreference {
     RequireDynamic,
@@ -244,7 +269,7 @@ pub trait CrateStore<'tcx> {
     // utility functions
     fn metadata_filename(&self) -> &str;
     fn metadata_section_name(&self, target: &Target) -> &str;
-    fn used_crates(&self, prefer: LinkagePreference) -> Vec<(CrateNum, Option<PathBuf>)>;
+    fn used_crates(&self, prefer: LinkagePreference) -> Vec<(CrateNum, LibSource)>;
     fn used_crate_source(&self, cnum: CrateNum) -> CrateSource;
     fn extern_mod_stmt_cnum(&self, emod_id: ast::NodeId) -> Option<CrateNum>;
     fn encode_metadata<'a>(&self, tcx: TyCtxt<'a, 'tcx, 'tcx>,
@@ -427,7 +452,7 @@ impl<'tcx> CrateStore<'tcx> for DummyCrateStore {
     // utility functions
     fn metadata_filename(&self) -> &str { bug!("metadata_filename") }
     fn metadata_section_name(&self, target: &Target) -> &str { bug!("metadata_section_name") }
-    fn used_crates(&self, prefer: LinkagePreference) -> Vec<(CrateNum, Option<PathBuf>)>
+    fn used_crates(&self, prefer: LinkagePreference) -> Vec<(CrateNum, LibSource)>
         { vec![] }
     fn used_crate_source(&self, cnum: CrateNum) -> CrateSource { bug!("used_crate_source") }
     fn extern_mod_stmt_cnum(&self, emod_id: ast::NodeId) -> Option<CrateNum> { None }

src/librustc/middle/dependency_format.rs

@@ -114,7 +114,7 @@ fn calculate_type(sess: &session::Session,
 
         // No linkage happens with rlibs, we just needed the metadata (which we
         // got long ago), so don't bother with anything.
-        config::CrateTypeRlib => return Vec::new(),
+        config::CrateTypeRlib | config::CrateTypeMetadata => return Vec::new(),
 
         // Staticlibs and cdylibs must have all static dependencies. If any fail
         // to be found, we generate some nice pretty errors.
@@ -192,7 +192,7 @@ fn calculate_type(sess: &session::Session,
         if src.dylib.is_none() &&
            !formats.contains_key(&cnum) &&
            sess.cstore.dep_kind(cnum) == DepKind::Explicit {
-            assert!(src.rlib.is_some());
+            assert!(src.rlib.is_some() || src.rmeta.is_some());
             info!("adding staticlib: {}", sess.cstore.crate_name(cnum));
             add_library(sess, cnum, RequireStatic, &mut formats);
             ret[cnum.as_usize() - 1] = Linkage::Static;

src/librustc/middle/reachable.rs

@@ -140,7 +140,7 @@ impl<'a, 'tcx> ReachableContext<'a, 'tcx> {
     fn new(tcx: TyCtxt<'a, 'tcx, 'tcx>) -> ReachableContext<'a, 'tcx> {
         let any_library = tcx.sess.crate_types.borrow().iter().any(|ty| {
             *ty == config::CrateTypeRlib || *ty == config::CrateTypeDylib ||
-            *ty == config::CrateTypeProcMacro
+            *ty == config::CrateTypeProcMacro || *ty == config::CrateTypeMetadata
         });
         ReachableContext {
             tcx: tcx,

src/librustc/middle/weak_lang_items.rs

@@ -75,7 +75,8 @@ fn verify(sess: &Session, items: &lang_items::LanguageItems) {
             config::CrateTypeCdylib |
             config::CrateTypeExecutable |
             config::CrateTypeStaticlib => true,
-            config::CrateTypeRlib => false,
+            config::CrateTypeRlib |
+            config::CrateTypeMetadata => false,
         }
     });
     if !needs_check {

src/librustc/session/config.rs

@@ -78,18 +78,6 @@ pub enum OutputType {
     DepInfo,
 }
 
-#[derive(Clone, Copy, Debug, PartialEq, Eq)]
-pub enum ErrorOutputType {
-    HumanReadable(ColorConfig),
-    Json,
-}
-
-impl Default for ErrorOutputType {
-    fn default() -> ErrorOutputType {
-        ErrorOutputType::HumanReadable(ColorConfig::Auto)
-    }
-}
-
 impl OutputType {
     fn is_compatible_with_codegen_units_and_single_output_file(&self) -> bool {
         match *self {
@@ -125,6 +113,18 @@ impl OutputType {
     }
 }
 
+#[derive(Clone, Copy, Debug, PartialEq, Eq)]
+pub enum ErrorOutputType {
+    HumanReadable(ColorConfig),
+    Json,
+}
+
+impl Default for ErrorOutputType {
+    fn default() -> ErrorOutputType {
+        ErrorOutputType::HumanReadable(ColorConfig::Auto)
+    }
+}
+
 // Use tree-based collections to cheaply get a deterministic Hash implementation.
 // DO NOT switch BTreeMap out for an unsorted container type! That would break
 // dependency tracking for commandline arguments.
@@ -483,6 +483,7 @@ pub enum CrateType {
     CrateTypeStaticlib,
     CrateTypeCdylib,
     CrateTypeProcMacro,
+    CrateTypeMetadata,
 }
 
 #[derive(Clone, Hash)]
@@ -1147,7 +1148,7 @@ pub fn rustc_short_optgroups() -> Vec<RustcOptGroup> {
                              assumed.", "[KIND=]NAME"),
         opt::multi_s("", "crate-type", "Comma separated list of types of crates
                                     for the compiler to emit",
-                   "[bin|lib|rlib|dylib|cdylib|staticlib]"),
+                   "[bin|lib|rlib|dylib|cdylib|staticlib|metadata]"),
         opt::opt_s("", "crate-name", "Specify the name of the crate being built",
                "NAME"),
         opt::multi_s("", "emit", "Comma separated list of types of output for \
@@ -1539,6 +1540,7 @@ pub fn parse_crate_types_from_list(list_list: Vec<String>) -> Result<Vec<CrateTy
                 "cdylib"    => CrateTypeCdylib,
                 "bin"       => CrateTypeExecutable,
                 "proc-macro" => CrateTypeProcMacro,
+                "metadata"  => CrateTypeMetadata,
                 _ => {
                     return Err(format!("unknown crate type: `{}`",
                                        part));
@@ -1623,6 +1625,7 @@ impl fmt::Display for CrateType {
             CrateTypeStaticlib => "staticlib".fmt(f),
             CrateTypeCdylib => "cdylib".fmt(f),
             CrateTypeProcMacro => "proc-macro".fmt(f),
+            CrateTypeMetadata => "metadata".fmt(f),
         }
     }
 }

src/librustc_driver/driver.rs

@@ -1182,6 +1182,9 @@ pub fn collect_crate_types(session: &Session, attrs: &[ast::Attribute]) -> Vec<c
                          Some(ref n) if *n == "rlib" => {
                              Some(config::CrateTypeRlib)
                          }
+                         Some(ref n) if *n == "metadata" => {
+                             Some(config::CrateTypeMetadata)
+                         }
                          Some(ref n) if *n == "dylib" => {
                              Some(config::CrateTypeDylib)
                          }

src/librustc_metadata/creader.rs

@@ -44,6 +44,7 @@ use log;
 pub struct Library {
     pub dylib: Option<(PathBuf, PathKind)>,
     pub rlib: Option<(PathBuf, PathKind)>,
+    pub rmeta: Option<(PathBuf, PathKind)>,
     pub metadata: MetadataBlob,
 }
 
@@ -62,10 +63,11 @@ fn dump_crates(cstore: &CStore) {
         info!("  cnum: {}", data.cnum);
         info!("  hash: {}", data.hash());
         info!("  reqd: {:?}", data.dep_kind.get());
-        let CrateSource { dylib, rlib } = data.source.clone();
+        let CrateSource { dylib, rlib, rmeta } = data.source.clone();
         dylib.map(|dl| info!("  dylib: {}", dl.0.display()));
         rlib.map(|rl|  info!("   rlib: {}", rl.0.display()));
-    })
+        rmeta.map(|rl| info!("   rmeta: {}", rl.0.display()));
+    });
 }
 
 #[derive(Debug)]
@@ -278,14 +280,15 @@ impl<'a> CrateLoader<'a> {
                 ident: ident.to_string(),
                 dylib: lib.dylib.clone().map(|p| p.0),
                 rlib:  lib.rlib.clone().map(|p| p.0),
+                rmeta: lib.rmeta.clone().map(|p| p.0),
             })
         } else {
             None
         };
         // Maintain a reference to the top most crate.
         let root = if root.is_some() { root } else { &crate_paths };
 
-        let Library { dylib, rlib, metadata } = lib;
+        let Library { dylib, rlib, rmeta, metadata } = lib;
 
         let cnum_map = self.resolve_crate_deps(root, &crate_root, &metadata, cnum, span, dep_kind);
 
@@ -305,6 +308,7 @@ impl<'a> CrateLoader<'a> {
             source: cstore::CrateSource {
                 dylib: dylib,
                 rlib: rlib,
+                rmeta: rmeta,
             },
         });
 
@@ -767,7 +771,8 @@ impl<'a> CrateLoader<'a> {
                 config::CrateTypeProcMacro |
                 config::CrateTypeCdylib |
                 config::CrateTypeStaticlib => need_lib_alloc = true,
-                config::CrateTypeRlib => {}
+                config::CrateTypeRlib |
+                config::CrateTypeMetadata => {}
             }
         }
         if !need_lib_alloc && !need_exe_alloc { return }

src/librustc_metadata/cstore.rs

@@ -25,7 +25,6 @@ use rustc::util::nodemap::{FxHashMap, NodeMap, NodeSet, DefIdMap};
 
 use std::cell::{RefCell, Cell};
 use std::rc::Rc;
-use std::path::PathBuf;
 use flate::Bytes;
 use syntax::{ast, attr};
 use syntax::ext::base::SyntaxExtension;
@@ -34,7 +33,7 @@ use syntax_pos;
 
 pub use rustc::middle::cstore::{NativeLibrary, LinkagePreference};
 pub use rustc::middle::cstore::{NativeStatic, NativeFramework, NativeUnknown};
-pub use rustc::middle::cstore::{CrateSource, LinkMeta};
+pub use rustc::middle::cstore::{CrateSource, LinkMeta, LibSource};
 
 // A map from external crate numbers (as decoded from some crate file) to
 // local crate numbers (as generated during this session). Each external
@@ -45,6 +44,7 @@ pub type CrateNumMap = IndexVec<CrateNum, CrateNum>;
 pub enum MetadataBlob {
     Inflated(Bytes),
     Archive(locator::ArchiveMetadata),
+    Raw(Vec<u8>),
 }
 
 /// Holds information about a syntax_pos::FileMap imported from another crate.
@@ -186,7 +186,7 @@ impl CStore {
     // positions.
     pub fn do_get_used_crates(&self,
                               prefer: LinkagePreference)
-                              -> Vec<(CrateNum, Option<PathBuf>)> {
+                              -> Vec<(CrateNum, LibSource)> {
         let mut ordering = Vec::new();
         for (&num, _) in self.metas.borrow().iter() {
             self.push_dependencies_in_postorder(&mut ordering, num);
@@ -202,6 +202,16 @@ impl CStore {
                     LinkagePreference::RequireDynamic => data.source.dylib.clone().map(|p| p.0),
                     LinkagePreference::RequireStatic => data.source.rlib.clone().map(|p| p.0),
                 };
+                let path = match path {
+                    Some(p) => LibSource::Some(p),
+                    None => {
+                        if data.source.rmeta.is_some() {
+                            LibSource::MetadataOnly
+                        } else {
+                            LibSource::None
+                        }
+                    }
+                };
                 Some((cnum, path))
             })
             .collect::<Vec<_>>();

src/librustc_metadata/cstore_impl.rs

@@ -13,7 +13,7 @@ use encoder;
 use locator;
 use schema;
 
-use rustc::middle::cstore::{InlinedItem, CrateStore, CrateSource, DepKind, ExternCrate};
+use rustc::middle::cstore::{InlinedItem, CrateStore, CrateSource, LibSource, DepKind, ExternCrate};
 use rustc::middle::cstore::{NativeLibrary, LinkMeta, LinkagePreference, LoadedMacro};
 use rustc::hir::def::{self, Def};
 use rustc::middle::lang_items;
@@ -28,7 +28,6 @@ use rustc::mir::Mir;
 use rustc::util::nodemap::{NodeSet, DefIdMap};
 use rustc_back::PanicStrategy;
 
-use std::path::PathBuf;
 use syntax::ast;
 use syntax::attr;
 use syntax::parse::new_parser_from_source_str;
@@ -545,7 +544,7 @@ impl<'tcx> CrateStore<'tcx> for cstore::CStore {
         locator::meta_section_name(target)
     }
 
-    fn used_crates(&self, prefer: LinkagePreference) -> Vec<(CrateNum, Option<PathBuf>)>
+    fn used_crates(&self, prefer: LinkagePreference) -> Vec<(CrateNum, LibSource)>
     {
         self.do_get_used_crates(prefer)
     }

src/librustc_metadata/decoder.rs

@@ -88,8 +88,9 @@ pub trait Metadata<'a, 'tcx>: Copy {
 impl<'a, 'tcx> Metadata<'a, 'tcx> for &'a MetadataBlob {
     fn raw_bytes(self) -> &'a [u8] {
         match *self {
-            MetadataBlob::Inflated(ref vec) => &vec[..],
+            MetadataBlob::Inflated(ref vec) => vec,
             MetadataBlob::Archive(ref ar) => ar.as_slice(),
+            MetadataBlob::Raw(ref vec) => vec,
         }
     }
 }