Restrict sysroot crate imports to those defined in this repo.

It's common to import dependencies from the sysroot via `extern crate`
rather than use an explicit cargo dependency, when it's necessary to use
the same dependency version as used by rustc itself. However, this is
dangerous for crates.io crates, since rustc may not pull in the
dependency on some targets, or may pull in multiple versions. In both
cases, the `extern crate` fails to resolve.

To address this, re-export all such dependencies from the appropriate
`rustc_*` crates, and use this alias from crates which would otherwise
need to use `extern crate`. Also use workspace dependencies for such
crates so that only one version can exist within the sysroot (since
otherwise it is meaningless to try to match the rustc version).

Author: Diggsey

Cargo.toml

@@ -60,6 +60,17 @@ exclude = [
   "obj",
 ]
 
+[workspace.dependencies]
+# These dependencies are either explicitly part of rustc's public interface, or
+# are "singleton" crates that we want to only appear once in the dependency graph.
+either = "1.5"
+smallvec = { version = "1.8.1", features = ["const_generics", "union", "may_dangle"] }
+indexmap = "2.4"
+tracing = "0.1.28"
+tracing-subscriber = { version = "0.3.3", default-features = false, features = ["fmt", "env-filter", "smallvec", "parking_lot", "ansi"] }
+pulldown-cmark = { version = "0.11", features = ["html"], default-features = false }
+thin-vec = "0.2.12"
+
 [profile.release.package.rustc_thread_pool]
 # The rustc fork of Rayon has deadlock detection code which intermittently
 # causes overflows in the CI (see https://github.com/rust-lang/rust/issues/90227)

compiler/rustc_abi/Cargo.toml

@@ -14,7 +14,7 @@ rustc_index = { path = "../rustc_index", default-features = false }
 rustc_macros = { path = "../rustc_macros", optional = true }
 rustc_serialize = { path = "../rustc_serialize", optional = true }
 rustc_span = { path = "../rustc_span", optional = true }
-tracing = "0.1"
+tracing = { workspace = true }
 # tidy-alphabetical-end
 
 [features]

compiler/rustc_arena/Cargo.toml

@@ -5,5 +5,5 @@ edition = "2024"
 
 [dependencies]
 # tidy-alphabetical-start
-smallvec = { version = "1.8.1", features = ["union", "may_dangle"] }
+smallvec = { workspace = true }
 # tidy-alphabetical-end

compiler/rustc_ast/Cargo.toml

@@ -14,7 +14,7 @@ rustc_index = { path = "../rustc_index" }
 rustc_macros = { path = "../rustc_macros" }
 rustc_serialize = { path = "../rustc_serialize" }
 rustc_span = { path = "../rustc_span" }
-smallvec = { version = "1.8.1", features = ["union", "may_dangle"] }
-thin-vec = "0.2.12"
-tracing = "0.1"
+smallvec = { workspace = true }
+thin-vec = { workspace = true }
+tracing = { workspace = true }
 # tidy-alphabetical-end

compiler/rustc_ast_lowering/Cargo.toml

@@ -24,7 +24,7 @@ rustc_middle = { path = "../rustc_middle" }
 rustc_session = { path = "../rustc_session" }
 rustc_span = { path = "../rustc_span" }
 rustc_target = { path = "../rustc_target" }
-smallvec = { version = "1.8.1", features = ["union", "may_dangle"] }
-thin-vec = "0.2.12"
-tracing = "0.1"
+smallvec = { workspace = true }
+thin-vec = { workspace = true }
+tracing = { workspace = true }
 # tidy-alphabetical-end

compiler/rustc_ast_passes/Cargo.toml

@@ -19,5 +19,5 @@ rustc_parse = { path = "../rustc_parse" }
 rustc_session = { path = "../rustc_session" }
 rustc_span = { path = "../rustc_span" }
 rustc_target = { path = "../rustc_target" }
-thin-vec = "0.2.12"
+thin-vec = { workspace = true }
 # tidy-alphabetical-end

compiler/rustc_ast_pretty/Cargo.toml

@@ -13,5 +13,5 @@ rustc_span = { path = "../rustc_span" }
 
 [dev-dependencies]
 # tidy-alphabetical-start
-thin-vec = "0.2.12"
+thin-vec = { workspace = true }
 # tidy-alphabetical-end

compiler/rustc_attr_data_structures/Cargo.toml

@@ -12,5 +12,5 @@ rustc_data_structures = {path = "../rustc_data_structures"}
 rustc_macros = {path = "../rustc_macros"}
 rustc_serialize = {path = "../rustc_serialize"}
 rustc_span = {path = "../rustc_span"}
-thin-vec = "0.2.12"
+thin-vec = { workspace = true }
 # tidy-alphabetical-end

compiler/rustc_attr_parsing/Cargo.toml

@@ -17,5 +17,5 @@ rustc_lexer = { path = "../rustc_lexer" }
 rustc_macros = { path = "../rustc_macros" }
 rustc_session = { path = "../rustc_session" }
 rustc_span = { path = "../rustc_span" }
-thin-vec = "0.2.12"
+thin-vec = { workspace = true }
 # tidy-alphabetical-end

compiler/rustc_borrowck/Cargo.toml

@@ -5,7 +5,7 @@ edition = "2024"
 
 [dependencies]
 # tidy-alphabetical-start
-either = "1.5.0"
+either = { workspace = true }
 itertools = "0.12"
 polonius-engine = "0.13.0"
 rustc_abi = { path = "../rustc_abi" }
@@ -24,6 +24,6 @@ rustc_session = { path = "../rustc_session" }
 rustc_span = { path = "../rustc_span" }
 rustc_trait_selection = { path = "../rustc_trait_selection" }
 rustc_traits = { path = "../rustc_traits" }
-smallvec = { version = "1.8.1", features = ["union", "may_dangle"] }
-tracing = "0.1"
+smallvec = { workspace = true }
+tracing = { workspace = true }
 # tidy-alphabetical-end

compiler/rustc_builtin_macros/Cargo.toml

@@ -30,7 +30,7 @@ rustc_proc_macro = { path = "../rustc_proc_macro" }
 rustc_session = { path = "../rustc_session" }
 rustc_span = { path = "../rustc_span" }
 rustc_target = { path = "../rustc_target" }
-smallvec = { version = "1.8.1", features = ["union", "may_dangle"] }
-thin-vec = "0.2.12"
-tracing = "0.1"
+smallvec = { workspace = true }
+thin-vec = { workspace = true }
+tracing = { workspace = true }
 # tidy-alphabetical-end

compiler/rustc_codegen_cranelift/src/lib.rs

@@ -26,13 +26,12 @@ extern crate rustc_fs_util;
 extern crate rustc_hir;
 extern crate rustc_incremental;
 extern crate rustc_index;
+extern crate rustc_log;
 extern crate rustc_metadata;
 extern crate rustc_session;
 extern crate rustc_span;
 extern crate rustc_symbol_mangling;
 extern crate rustc_target;
-#[macro_use]
-extern crate tracing;
 
 // This prevents duplicating functions and statics that are already part of the host rustc process.
 #[allow(unused_extern_crates)]
@@ -46,6 +45,7 @@ use cranelift_codegen::isa::TargetIsa;
 use cranelift_codegen::settings::{self, Configurable};
 use rustc_codegen_ssa::traits::CodegenBackend;
 use rustc_codegen_ssa::{CodegenResults, TargetConfig};
+use rustc_log::tracing::info;
 use rustc_middle::dep_graph::{WorkProduct, WorkProductId};
 use rustc_session::Session;
 use rustc_session::config::OutputFilenames;

compiler/rustc_codegen_gcc/src/back/lto.rs

@@ -32,6 +32,7 @@ use rustc_codegen_ssa::{ModuleCodegen, ModuleKind, looks_like_rust_object_file};
 use rustc_data_structures::memmap::Mmap;
 use rustc_errors::{DiagCtxtHandle, FatalError};
 use rustc_hir::def_id::LOCAL_CRATE;
+use rustc_log::tracing::info;
 use rustc_middle::bug;
 use rustc_middle::dep_graph::WorkProduct;
 use rustc_middle::middle::exported_symbols::{SymbolExportInfo, SymbolExportLevel};

compiler/rustc_codegen_gcc/src/back/write.rs

@@ -6,6 +6,7 @@ use rustc_codegen_ssa::back::write::{BitcodeSection, CodegenContext, EmitObj, Mo
 use rustc_codegen_ssa::{CompiledModule, ModuleCodegen};
 use rustc_errors::DiagCtxtHandle;
 use rustc_fs_util::link_or_copy;
+use rustc_log::tracing::debug;
 use rustc_session::config::OutputType;
 use rustc_span::fatal_error::FatalError;
 use rustc_target::spec::SplitDebuginfo;

compiler/rustc_codegen_gcc/src/consts.rs

@@ -6,6 +6,7 @@ use rustc_codegen_ssa::traits::{
     BaseTypeCodegenMethods, ConstCodegenMethods, StaticCodegenMethods,
 };
 use rustc_hir::def::DefKind;
+use rustc_log::tracing::trace;
 use rustc_middle::middle::codegen_fn_attrs::{CodegenFnAttrFlags, CodegenFnAttrs};
 use rustc_middle::mir::interpret::{
     self, ConstAllocation, ErrorHandled, Scalar as InterpScalar, read_target_uint,

compiler/rustc_codegen_gcc/src/gcc_util.rs

@@ -1,8 +1,8 @@
 #[cfg(feature = "master")]
 use gccjit::Context;
 use rustc_codegen_ssa::target_features;
+use rustc_data_structures::smallvec::{SmallVec, smallvec};
 use rustc_session::Session;
-use smallvec::{SmallVec, smallvec};
 
 fn gcc_features_by_flags(sess: &Session, features: &mut Vec<String>) {
     target_features::retpoline_features_by_flags(sess, features);

compiler/rustc_codegen_gcc/src/lib.rs

@@ -26,12 +26,6 @@
 #![deny(clippy::pattern_type_mismatch)]
 #![allow(clippy::needless_lifetimes, clippy::uninlined_format_args)]
 
-// These crates are pulled from the sysroot because they are part of
-// rustc's public API, so we need to ensure version compatibility.
-extern crate smallvec;
-#[macro_use]
-extern crate tracing;
-
 // The rustc crates we need
 extern crate rustc_abi;
 extern crate rustc_apfloat;
@@ -46,6 +40,7 @@ extern crate rustc_hir;
 extern crate rustc_index;
 #[cfg(feature = "master")]
 extern crate rustc_interface;
+extern crate rustc_log;
 extern crate rustc_macros;
 extern crate rustc_middle;
 extern crate rustc_session;

compiler/rustc_codegen_llvm/Cargo.toml

@@ -40,6 +40,6 @@ rustc_symbol_mangling = { path = "../rustc_symbol_mangling" }
 rustc_target = { path = "../rustc_target" }
 serde = { version = "1", features = [ "derive" ]}
 serde_json = "1"
-smallvec = { version = "1.8.1", features = ["union", "may_dangle"] }
-tracing = "0.1"
+smallvec = { workspace = true }
+tracing = { workspace = true }
 # tidy-alphabetical-end

compiler/rustc_codegen_ssa/Cargo.toml

@@ -38,11 +38,11 @@ rustc_symbol_mangling = { path = "../rustc_symbol_mangling" }
 rustc_target = { path = "../rustc_target" }
 rustc_trait_selection = { path = "../rustc_trait_selection" }
 serde_json = "1.0.59"
-smallvec = { version = "1.8.1", features = ["union", "may_dangle"] }
+smallvec = { workspace = true }
 tempfile = "3.2"
-thin-vec = "0.2.12"
+thin-vec = { workspace = true }
 thorin-dwp = "0.9"
-tracing = "0.1"
+tracing = { workspace = true }
 wasm-encoder = "0.219"
 # tidy-alphabetical-end
 

compiler/rustc_const_eval/Cargo.toml

@@ -5,7 +5,7 @@ edition = "2024"
 
 [dependencies]
 # tidy-alphabetical-start
-either = "1"
+either = { workspace = true }
 rustc_abi = { path = "../rustc_abi" }
 rustc_apfloat = "0.2.0"
 rustc_ast = { path = "../rustc_ast" }
@@ -23,5 +23,5 @@ rustc_session = { path = "../rustc_session" }
 rustc_span = { path = "../rustc_span" }
 rustc_target = { path = "../rustc_target" }
 rustc_trait_selection = { path = "../rustc_trait_selection" }
-tracing = "0.1"
+tracing = { workspace = true }
 # tidy-alphabetical-end

compiler/rustc_data_structures/Cargo.toml

@@ -7,10 +7,10 @@ edition = "2024"
 # tidy-alphabetical-start
 arrayvec = { version = "0.7", default-features = false }
 bitflags = "2.4.1"
-either = "1.0"
+either = { workspace = true }
 elsa = "1.11.0"
 ena = "0.14.3"
-indexmap = "2.4.0"
+indexmap = { workspace = true }
 jobserver_crate = { version = "0.1.28", package = "jobserver" }
 measureme = "12.0.1"
 rustc-hash = "2.0.0"
@@ -22,11 +22,11 @@ rustc_index = { path = "../rustc_index", package = "rustc_index" }
 rustc_macros = { path = "../rustc_macros" }
 rustc_serialize = { path = "../rustc_serialize" }
 rustc_thread_pool = { path = "../rustc_thread_pool" }
-smallvec = { version = "1.8.1", features = ["const_generics", "union", "may_dangle"] }
+smallvec = { workspace = true }
 stacker = "0.1.17"
 tempfile = "3.2"
-thin-vec = "0.2.12"
-tracing = "0.1"
+thin-vec = { workspace = true }
+tracing = { workspace = true }
 # tidy-alphabetical-end
 
 [dependencies.hashbrown]

compiler/rustc_data_structures/src/lib.rs

@@ -43,6 +43,7 @@ use std::fmt;
 pub use atomic_ref::AtomicRef;
 pub use ena::{snapshot_vec, undo_log, unify};
 pub use rustc_index::static_assert_size;
+pub use {either, indexmap, smallvec, thin_vec};
 
 pub mod aligned;
 pub mod base_n;

compiler/rustc_driver_impl/Cargo.toml

@@ -51,7 +51,7 @@ rustc_ty_utils = { path = "../rustc_ty_utils" }
 serde_json = "1.0.59"
 shlex = "1.0"
 stable_mir = { path = "../stable_mir", features = ["rustc_internal"] }
-tracing = { version = "0.1.35" }
+tracing = { workspace = true }
 # tidy-alphabetical-end
 
 [target.'cfg(all(unix, any(target_env = "gnu", target_os = "macos")))'.dependencies]

compiler/rustc_error_messages/Cargo.toml

@@ -16,6 +16,6 @@ rustc_data_structures = { path = "../rustc_data_structures" }
 rustc_macros = { path = "../rustc_macros" }
 rustc_serialize = { path = "../rustc_serialize" }
 rustc_span = { path = "../rustc_span" }
-tracing = "0.1"
+tracing = { workspace = true }
 unic-langid = { version = "0.9.0", features = ["macros"] }
 # tidy-alphabetical-end

compiler/rustc_errors/Cargo.toml

@@ -29,7 +29,7 @@ serde = { version = "1.0.125", features = [ "derive" ] }
 serde_json = "1.0.59"
 termcolor = "1.2.0"
 termize = "0.2"
-tracing = "0.1"
+tracing = { workspace = true }
 # tidy-alphabetical-end
 
 [target.'cfg(windows)'.dependencies.windows]

compiler/rustc_expand/Cargo.toml

@@ -29,7 +29,7 @@ rustc_proc_macro = { path = "../rustc_proc_macro" }
 rustc_serialize = { path = "../rustc_serialize" }
 rustc_session = { path = "../rustc_session" }
 rustc_span = { path = "../rustc_span" }
-smallvec = { version = "1.8.1", features = ["union", "may_dangle"] }
-thin-vec = "0.2.12"
-tracing = "0.1"
+smallvec = { workspace = true }
+thin-vec = { workspace = true }
+tracing = { workspace = true }
 # tidy-alphabetical-end

compiler/rustc_hir/Cargo.toml

@@ -17,7 +17,7 @@ rustc_macros = { path = "../rustc_macros" }
 rustc_serialize = { path = "../rustc_serialize" }
 rustc_span = { path = "../rustc_span" }
 rustc_target = { path = "../rustc_target" }
-smallvec = { version = "1.8.1", features = ["union", "may_dangle"] }
-thin-vec = "0.2.12"
-tracing = "0.1"
+smallvec = { workspace = true }
+thin-vec = { workspace = true }
+tracing = { workspace = true }
 # tidy-alphabetical-end

compiler/rustc_hir_analysis/Cargo.toml

@@ -29,6 +29,6 @@ rustc_session = { path = "../rustc_session" }
 rustc_span = { path = "../rustc_span" }
 rustc_target = { path = "../rustc_target" }
 rustc_trait_selection = { path = "../rustc_trait_selection" }
-smallvec = { version = "1.8.1", features = ["union", "may_dangle"] }
-tracing = "0.1"
+smallvec = { workspace = true }
+tracing = { workspace = true }
 # tidy-alphabetical-end

compiler/rustc_hir_typeck/Cargo.toml

@@ -25,6 +25,6 @@ rustc_session = { path = "../rustc_session" }
 rustc_span = { path = "../rustc_span" }
 rustc_target = { path = "../rustc_target" }
 rustc_trait_selection = { path = "../rustc_trait_selection" }
-smallvec = { version = "1.8.1", features = ["union", "may_dangle"] }
-tracing = "0.1"
+smallvec = { workspace = true }
+tracing = { workspace = true }
 # tidy-alphabetical-end

compiler/rustc_incremental/Cargo.toml

@@ -19,6 +19,6 @@ rustc_middle = { path = "../rustc_middle" }
 rustc_serialize = { path = "../rustc_serialize" }
 rustc_session = { path = "../rustc_session" }
 rustc_span = { path = "../rustc_span" }
-thin-vec = "0.2.12"
-tracing = "0.1"
+thin-vec = { workspace = true }
+tracing = { workspace = true }
 # tidy-alphabetical-end

compiler/rustc_index/Cargo.toml

@@ -8,7 +8,7 @@ edition = "2024"
 rustc_index_macros = { path = "../rustc_index_macros" }
 rustc_macros = { path = "../rustc_macros", optional = true }
 rustc_serialize = { path = "../rustc_serialize", optional = true }
-smallvec = "1.8.1"
+smallvec = { workspace = true }
 # tidy-alphabetical-end
 
 [features]

compiler/rustc_infer/Cargo.toml

@@ -17,7 +17,7 @@ rustc_macros = { path = "../rustc_macros" }
 rustc_middle = { path = "../rustc_middle" }
 rustc_span = { path = "../rustc_span" }
 rustc_type_ir = { path = "../rustc_type_ir" }
-smallvec = { version = "1.8.1", features = ["union", "may_dangle"] }
-thin-vec = "0.2.12"
-tracing = "0.1"
+smallvec = { workspace = true }
+thin-vec = { workspace = true }
+tracing = { workspace = true }
 # tidy-alphabetical-end

compiler/rustc_interface/Cargo.toml

@@ -46,7 +46,7 @@ rustc_thread_pool = { path = "../rustc_thread_pool" }
 rustc_trait_selection = { path = "../rustc_trait_selection" }
 rustc_traits = { path = "../rustc_traits" }
 rustc_ty_utils = { path = "../rustc_ty_utils" }
-tracing = "0.1"
+tracing = { workspace = true }
 # tidy-alphabetical-end
 
 [dev-dependencies]

compiler/rustc_lint/Cargo.toml

@@ -24,7 +24,7 @@ rustc_session = { path = "../rustc_session" }
 rustc_span = { path = "../rustc_span" }
 rustc_target = { path = "../rustc_target" }
 rustc_trait_selection = { path = "../rustc_trait_selection" }
-smallvec = { version = "1.8.1", features = ["union", "may_dangle"] }
-tracing = "0.1"
+smallvec = { workspace = true }
+tracing = { workspace = true }
 unicode-security = "0.1.0"
 # tidy-alphabetical-end

compiler/rustc_log/Cargo.toml

@@ -5,9 +5,9 @@ edition = "2024"
 
 [dependencies]
 # tidy-alphabetical-start
-tracing = "0.1.28"
+tracing = { workspace = true }
 tracing-core = "=0.1.30" # FIXME(Nilstrieb) tracing has a deadlock: https://github.com/tokio-rs/tracing/issues/2635
-tracing-subscriber = { version = "0.3.3", default-features = false, features = ["fmt", "env-filter", "smallvec", "parking_lot", "ansi"] }
+tracing-subscriber = { workspace = true }
 tracing-tree = "0.3.1"
 # tidy-alphabetical-end