From ac9aed56e4dc62c4959ae0c14cec585994302c93 Mon Sep 17 00:00:00 2001 From: Tomas Tauber <2410580+tomtau@users.noreply.github.com> Date: Fri, 27 Sep 2019 21:32:04 +0800 Subject: [PATCH] getting more context for duplicate lang items (fixes #60561) Where possible, the error message includes the name of the crate that brought in the crate with duplicate lang items (which helps with debugging). This information is passed on from cstore using the `extern_crate` query. --- src/librustc/middle/cstore.rs | 9 ++++- src/librustc/middle/lang_items.rs | 34 ++++++++++++++++--- src/librustc/ty/print/pretty.rs | 2 +- src/librustc_metadata/creader.rs | 15 ++++---- src/librustc_metadata/cstore_impl.rs | 2 +- src/test/ui/duplicate_entry_error.stderr | 2 +- src/test/ui/error-codes/E0152.stderr | 2 +- .../ui/panic-handler/panic-handler-std.stderr | 2 +- 8 files changed, 50 insertions(+), 18 deletions(-) diff --git a/src/librustc/middle/cstore.rs b/src/librustc/middle/cstore.rs index de84fcd7160df..ddf6262b7382e 100644 --- a/src/librustc/middle/cstore.rs +++ b/src/librustc/middle/cstore.rs @@ -126,10 +126,17 @@ pub struct ExternCrate { /// used to select the extern with the shortest path pub path_len: usize, + /// Crate that depends on this crate + pub dependency_of: CrateNum, +} + +impl ExternCrate { /// If true, then this crate is the crate named by the extern /// crate referenced above. If false, then this crate is a dep /// of the crate. - pub direct: bool, + pub fn is_direct(&self) -> bool { + self.dependency_of == LOCAL_CRATE + } } #[derive(Copy, Clone, Debug, HashStable)] diff --git a/src/librustc/middle/lang_items.rs b/src/librustc/middle/lang_items.rs index c5d9a722ae18e..cab929389d6a4 100644 --- a/src/librustc/middle/lang_items.rs +++ b/src/librustc/middle/lang_items.rs @@ -13,6 +13,7 @@ use crate::hir::def_id::DefId; use crate::hir::check_attr::Target; use crate::ty::{self, TyCtxt}; use crate::middle::weak_lang_items; +use crate::middle::cstore::ExternCrate; use crate::util::nodemap::FxHashMap; use syntax::ast; @@ -182,16 +183,39 @@ impl LanguageItemCollector<'tcx> { E0152, "duplicate lang item found: `{}`.", name), - None => self.tcx.sess.struct_err(&format!( - "duplicate lang item in crate `{}`: `{}`.", - self.tcx.crate_name(item_def_id.krate), - name)), + None => { + match self.tcx.extern_crate(item_def_id) { + Some(ExternCrate {dependency_of, ..}) => { + self.tcx.sess.struct_err(&format!( + "duplicate lang item in crate `{}` (which `{}` depends on): `{}`.", + self.tcx.crate_name(item_def_id.krate), + self.tcx.crate_name(*dependency_of), + name)) + }, + _ => { + self.tcx.sess.struct_err(&format!( + "duplicate lang item in crate `{}`: `{}`.", + self.tcx.crate_name(item_def_id.krate), + name)) + } + } + }, }; if let Some(span) = self.tcx.hir().span_if_local(original_def_id) { span_note!(&mut err, span, "first defined here."); } else { - err.note(&format!("first defined in crate `{}`.", + match self.tcx.extern_crate(original_def_id) { + Some(ExternCrate {dependency_of, ..}) => { + err.note(&format!( + "first defined in crate `{}` (which `{}` depends on).", + self.tcx.crate_name(original_def_id.krate), + self.tcx.crate_name(*dependency_of))); + }, + _ => { + err.note(&format!("first defined in crate `{}`.", self.tcx.crate_name(original_def_id.krate))); + } + } } err.emit(); } diff --git a/src/librustc/ty/print/pretty.rs b/src/librustc/ty/print/pretty.rs index 2bc87d6b8ba5e..fe0d0fad3a565 100644 --- a/src/librustc/ty/print/pretty.rs +++ b/src/librustc/ty/print/pretty.rs @@ -278,7 +278,7 @@ pub trait PrettyPrinter<'tcx>: match self.tcx().extern_crate(def_id) { Some(&ExternCrate { src: ExternCrateSource::Extern(def_id), - direct: true, + dependency_of: LOCAL_CRATE, span, .. }) => { diff --git a/src/librustc_metadata/creader.rs b/src/librustc_metadata/creader.rs index af41b6a4c857f..91b9f38ebce1f 100644 --- a/src/librustc_metadata/creader.rs +++ b/src/librustc_metadata/creader.rs @@ -17,6 +17,7 @@ use rustc::middle::cstore::{ExternCrate, ExternCrateSource}; use rustc::util::common::record_time; use rustc::util::nodemap::FxHashSet; use rustc::hir::map::Definitions; +use rustc::hir::def_id::LOCAL_CRATE; use std::ops::Deref; use std::path::PathBuf; @@ -430,7 +431,7 @@ impl<'a> CrateLoader<'a> { mut extern_crate: ExternCrate, visited: &mut FxHashSet<(CrateNum, bool)>) { - if !visited.insert((cnum, extern_crate.direct)) { return } + if !visited.insert((cnum, extern_crate.is_direct())) { return } let cmeta = self.cstore.get_crate_data(cnum); let mut old_extern_crate = cmeta.extern_crate.borrow_mut(); @@ -441,14 +442,14 @@ impl<'a> CrateLoader<'a> { // - shorter paths to longer (tuple.2). let new_rank = ( true, - extern_crate.direct, + extern_crate.is_direct(), cmp::Reverse(extern_crate.path_len), ); let old_rank = match *old_extern_crate { None => (false, false, cmp::Reverse(usize::max_value())), Some(ref c) => ( true, - c.direct, + c.is_direct(), cmp::Reverse(c.path_len), ), }; @@ -460,7 +461,7 @@ impl<'a> CrateLoader<'a> { drop(old_extern_crate); // Propagate the extern crate info to dependencies. - extern_crate.direct = false; + extern_crate.dependency_of = cnum; for &dep_cnum in cmeta.dependencies.borrow().iter() { self.update_extern_crate(dep_cnum, extern_crate, visited); } @@ -1030,7 +1031,7 @@ impl<'a> CrateLoader<'a> { src: ExternCrateSource::Extern(def_id), span: item.span, path_len, - direct: true, + dependency_of: LOCAL_CRATE, }, &mut FxHashSet::default(), ); @@ -1057,7 +1058,7 @@ impl<'a> CrateLoader<'a> { span, // to have the least priority in `update_extern_crate` path_len: usize::max_value(), - direct: true, + dependency_of: LOCAL_CRATE, }, &mut FxHashSet::default(), ); @@ -1081,7 +1082,7 @@ impl<'a> CrateLoader<'a> { span, // to have the least priority in `update_extern_crate` path_len: usize::max_value(), - direct: true, + dependency_of: LOCAL_CRATE, }, &mut FxHashSet::default(), ); diff --git a/src/librustc_metadata/cstore_impl.rs b/src/librustc_metadata/cstore_impl.rs index 11121ee875dda..0cca4dfa4c5ef 100644 --- a/src/librustc_metadata/cstore_impl.rs +++ b/src/librustc_metadata/cstore_impl.rs @@ -233,7 +233,7 @@ provide! { <'tcx> tcx, def_id, other, cdata, missing_extern_crate_item => { let r = match *cdata.extern_crate.borrow() { - Some(extern_crate) if !extern_crate.direct => true, + Some(extern_crate) if !extern_crate.is_direct() => true, _ => false, }; r diff --git a/src/test/ui/duplicate_entry_error.stderr b/src/test/ui/duplicate_entry_error.stderr index 1892ad38a594b..02be11d1fd0e5 100644 --- a/src/test/ui/duplicate_entry_error.stderr +++ b/src/test/ui/duplicate_entry_error.stderr @@ -7,7 +7,7 @@ LL | | loop {} LL | | } | |_^ | - = note: first defined in crate `std`. + = note: first defined in crate `std` (which `duplicate_entry_error` depends on). error: aborting due to previous error diff --git a/src/test/ui/error-codes/E0152.stderr b/src/test/ui/error-codes/E0152.stderr index 26e6e2e1bce7e..d4b59a1148e60 100644 --- a/src/test/ui/error-codes/E0152.stderr +++ b/src/test/ui/error-codes/E0152.stderr @@ -4,7 +4,7 @@ error[E0152]: duplicate lang item found: `arc`. LL | struct Foo; | ^^^^^^^^^^^ | - = note: first defined in crate `alloc`. + = note: first defined in crate `alloc` (which `std` depends on). error: aborting due to previous error diff --git a/src/test/ui/panic-handler/panic-handler-std.stderr b/src/test/ui/panic-handler/panic-handler-std.stderr index 3224031111650..e6d24348ca825 100644 --- a/src/test/ui/panic-handler/panic-handler-std.stderr +++ b/src/test/ui/panic-handler/panic-handler-std.stderr @@ -6,7 +6,7 @@ LL | | loop {} LL | | } | |_^ | - = note: first defined in crate `std`. + = note: first defined in crate `std` (which `panic_handler_std` depends on). error: argument should be `&PanicInfo` --> $DIR/panic-handler-std.rs:7:16