diff --git a/src/libcollections/string.rs b/src/libcollections/string.rs
index cd6f27bf65f6e..7eccd5fa3b605 100644
--- a/src/libcollections/string.rs
+++ b/src/libcollections/string.rs
@@ -25,6 +25,7 @@ use core::mem;
use core::ops::{self, Deref, Add, Index};
use core::ptr;
use core::slice;
+use core::str::Pattern;
use unicode::str as unicode_str;
use unicode::str::Utf16Item;
@@ -765,6 +766,25 @@ impl<'a> Extend<&'a str> for String {
}
}
+/// A convenience impl that delegates to the impl for `&str`
+impl<'a, 'b> Pattern<'a> for &'b String {
+ type Searcher = <&'b str as Pattern<'a>>::Searcher;
+
+ fn into_searcher(self, haystack: &'a str) -> <&'b str as Pattern<'a>>::Searcher {
+ self[..].into_searcher(haystack)
+ }
+
+ #[inline]
+ fn is_contained_in(self, haystack: &'a str) -> bool {
+ self[..].is_contained_in(haystack)
+ }
+
+ #[inline]
+ fn is_prefix_of(self, haystack: &'a str) -> bool {
+ self[..].is_prefix_of(haystack)
+ }
+}
+
#[stable(feature = "rust1", since = "1.0.0")]
impl PartialEq for String {
#[inline]
diff --git a/src/libcore/str/pattern.rs b/src/libcore/str/pattern.rs
index 7bf248917a5cd..98b6533980dd9 100644
--- a/src/libcore/str/pattern.rs
+++ b/src/libcore/str/pattern.rs
@@ -474,22 +474,16 @@ impl<'a, 'b> Pattern<'a> for &'b [char] {
s, CharEqPattern(s));
}
+/// A convenience impl that delegates to the impl for `&str`
+impl<'a, 'b> Pattern<'a> for &'b &'b str {
+ type Searcher = <&'b str as Pattern<'a>>::Searcher;
+ associated_items!(<&'b str as Pattern<'a>>::Searcher,
+ s, (*s));
+}
+
/// Searches for chars that match the given predicate
impl<'a, F> Pattern<'a> for F where F: FnMut(char) -> bool {
type Searcher = <CharEqPattern<Self> as Pattern<'a>>::Searcher;
associated_items!(<CharEqPattern<Self> as Pattern<'a>>::Searcher,
s, CharEqPattern(s));
}
-
-// Deref-forward impl
-
-use ops::Deref;
-
-/// Delegates to the next deref coercion of `Self` that implements `Pattern`
-impl<'a, 'b, P: 'b + ?Sized, T: Deref<Target = P> + ?Sized> Pattern<'a> for &'b T
- where &'b P: Pattern<'a>
-{
- type Searcher = <&'b P as Pattern<'a>>::Searcher;
- associated_items!(<&'b P as Pattern<'a>>::Searcher,
- s, (&**s));
-}
diff --git a/src/libcoretest/str.rs b/src/libcoretest/str.rs
index cac78363dd53b..38cab4f0e0942 100644
--- a/src/libcoretest/str.rs
+++ b/src/libcoretest/str.rs
@@ -13,9 +13,7 @@ fn test_pattern_deref_forward() {
let data = "aabcdaa";
assert!(data.contains("bcd"));
assert!(data.contains(&"bcd"));
- assert!(data.contains(&&"bcd"));
assert!(data.contains(&"bcd".to_string()));
- assert!(data.contains(&&"bcd".to_string()));
}
#[test]
diff --git a/src/librustc/middle/traits/error_reporting.rs b/src/librustc/middle/traits/error_reporting.rs
index d2b5b460d1420..d10ff060418cc 100644
--- a/src/librustc/middle/traits/error_reporting.rs
+++ b/src/librustc/middle/traits/error_reporting.rs
@@ -12,6 +12,7 @@ use super::{
FulfillmentError,
FulfillmentErrorCode,
MismatchedProjectionTypes,
+ Obligation,
ObligationCauseCode,
OutputTypeParameterMismatch,
PredicateObligation,
@@ -21,6 +22,7 @@ use super::{
use fmt_macros::{Parser, Piece, Position};
use middle::infer::InferCtxt;
use middle::ty::{self, AsPredicate, ReferencesError, ToPolyTraitRef, TraitRef};
+use middle::ty_fold::TypeFoldable;
use std::collections::HashMap;
use syntax::codemap::{DUMMY_SP, Span};
use syntax::attr::{AttributeMethods, AttrMetaMethods};
@@ -137,24 +139,36 @@ fn report_on_unimplemented<'a, 'tcx>(infcx: &InferCtxt<'a, 'tcx>,
report
}
+/// Reports that an overflow has occurred and halts compilation. We
+/// halt compilation unconditionally because it is important that
+/// overflows never be masked -- they basically represent computations
+/// whose result could not be truly determined and thus we can't say
+/// if the program type checks or not -- and they are unusual
+/// occurrences in any case.
+pub fn report_overflow_error<'a, 'tcx, T>(infcx: &InferCtxt<'a, 'tcx>,
+ obligation: &Obligation<'tcx, T>)
+ -> !
+ where T: UserString<'tcx> + TypeFoldable<'tcx>
+{
+ let predicate =
+ infcx.resolve_type_vars_if_possible(&obligation.predicate);
+ span_err!(infcx.tcx.sess, obligation.cause.span, E0275,
+ "overflow evaluating the requirement `{}`",
+ predicate.user_string(infcx.tcx));
+
+ suggest_new_overflow_limit(infcx.tcx, obligation.cause.span);
+
+ note_obligation_cause(infcx, obligation);
+
+ infcx.tcx.sess.abort_if_errors();
+ unreachable!();
+}
+
pub fn report_selection_error<'a, 'tcx>(infcx: &InferCtxt<'a, 'tcx>,
obligation: &PredicateObligation<'tcx>,
error: &SelectionError<'tcx>)
{
match *error {
- SelectionError::Overflow => {
- // We could track the stack here more precisely if we wanted, I imagine.
- let predicate =
- infcx.resolve_type_vars_if_possible(&obligation.predicate);
- span_err!(infcx.tcx.sess, obligation.cause.span, E0275,
- "overflow evaluating the requirement `{}`",
- predicate.user_string(infcx.tcx));
-
- suggest_new_overflow_limit(infcx.tcx, obligation.cause.span);
-
- note_obligation_cause(infcx, obligation);
- }
-
SelectionError::Unimplemented => {
match &obligation.cause.code {
&ObligationCauseCode::CompareImplMethodObligation => {
@@ -309,8 +323,9 @@ pub fn maybe_report_ambiguity<'a, 'tcx>(infcx: &InferCtxt<'a, 'tcx>,
}
}
-fn note_obligation_cause<'a, 'tcx>(infcx: &InferCtxt<'a, 'tcx>,
- obligation: &PredicateObligation<'tcx>)
+fn note_obligation_cause<'a, 'tcx, T>(infcx: &InferCtxt<'a, 'tcx>,
+ obligation: &Obligation<'tcx, T>)
+ where T: UserString<'tcx>
{
note_obligation_cause_code(infcx,
&obligation.predicate,
@@ -318,10 +333,11 @@ fn note_obligation_cause<'a, 'tcx>(infcx: &InferCtxt<'a, 'tcx>,
&obligation.cause.code);
}
-fn note_obligation_cause_code<'a, 'tcx>(infcx: &InferCtxt<'a, 'tcx>,
- predicate: &ty::Predicate<'tcx>,
- cause_span: Span,
- cause_code: &ObligationCauseCode<'tcx>)
+fn note_obligation_cause_code<'a, 'tcx, T>(infcx: &InferCtxt<'a, 'tcx>,
+ predicate: &T,
+ cause_span: Span,
+ cause_code: &ObligationCauseCode<'tcx>)
+ where T: UserString<'tcx>
{
let tcx = infcx.tcx;
match *cause_code {
diff --git a/src/librustc/middle/traits/mod.rs b/src/librustc/middle/traits/mod.rs
index f46cac308287b..24b201c960f16 100644
--- a/src/librustc/middle/traits/mod.rs
+++ b/src/librustc/middle/traits/mod.rs
@@ -23,9 +23,10 @@ use std::slice::Iter;
use std::rc::Rc;
use syntax::ast;
use syntax::codemap::{Span, DUMMY_SP};
-use util::ppaux::{Repr, UserString};
+use util::ppaux::Repr;
pub use self::error_reporting::report_fulfillment_errors;
+pub use self::error_reporting::report_overflow_error;
pub use self::error_reporting::suggest_new_overflow_limit;
pub use self::coherence::orphan_check;
pub use self::coherence::overlapping_impls;
@@ -151,7 +152,6 @@ pub type Selection<'tcx> = Vtable<'tcx, PredicateObligation<'tcx>>;
#[derive(Clone,Debug)]
pub enum SelectionError<'tcx> {
Unimplemented,
- Overflow,
OutputTypeParameterMismatch(ty::PolyTraitRef<'tcx>,
ty::PolyTraitRef<'tcx>,
ty::type_err<'tcx>),
@@ -327,16 +327,9 @@ pub fn evaluate_builtin_bound<'a,'tcx>(infcx: &InferCtxt<'a,'tcx>,
let result = match fulfill_cx.select_all_or_error(infcx, typer) {
Ok(()) => Ok(Some(())), // Success, we know it implements Copy.
Err(errors) => {
- // Check if overflow occurred anywhere and propagate that.
- if errors.iter().any(
- |err| match err.code { CodeSelectionError(Overflow) => true, _ => false })
- {
- return Err(Overflow);
- }
-
- // Otherwise, if there were any hard errors, propagate an
- // arbitrary one of those. If no hard errors at all,
- // report ambiguity.
+ // If there were any hard errors, propagate an arbitrary
+ // one of those. If no hard errors at all, report
+ // ambiguity.
let sel_error =
errors.iter()
.filter_map(|err| {
@@ -384,16 +377,8 @@ pub fn type_known_to_meet_builtin_bound<'a,'tcx>(infcx: &InferCtxt<'a,'tcx>,
// soldering on, so just treat this like not implemented
false
}
- Err(Overflow) => {
- span_err!(infcx.tcx.sess, span, E0285,
- "overflow evaluating whether `{}` is `{}`",
- ty.user_string(infcx.tcx),
- bound.user_string(infcx.tcx));
- suggest_new_overflow_limit(infcx.tcx, span);
- false
- }
Err(_) => {
- // other errors: not implemented.
+ // errors: not implemented.
false
}
}
@@ -652,15 +637,6 @@ impl<'tcx> FulfillmentError<'tcx> {
{
FulfillmentError { obligation: obligation, code: code }
}
-
- pub fn is_overflow(&self) -> bool {
- match self.code {
- CodeAmbiguity => false,
- CodeSelectionError(Overflow) => true,
- CodeSelectionError(_) => false,
- CodeProjectionError(_) => false,
- }
- }
}
impl<'tcx> TraitObligation<'tcx> {
diff --git a/src/librustc/middle/traits/project.rs b/src/librustc/middle/traits/project.rs
index 6b66d7227d300..a67410998c727 100644
--- a/src/librustc/middle/traits/project.rs
+++ b/src/librustc/middle/traits/project.rs
@@ -11,9 +11,9 @@
//! Code for projecting associated types out of trait references.
use super::elaborate_predicates;
+use super::report_overflow_error;
use super::Obligation;
use super::ObligationCause;
-use super::Overflow;
use super::PredicateObligation;
use super::SelectionContext;
use super::SelectionError;
@@ -442,7 +442,7 @@ fn project_type<'cx,'tcx>(
let recursion_limit = selcx.tcx().sess.recursion_limit.get();
if obligation.recursion_depth >= recursion_limit {
debug!("project: overflow!");
- return Err(ProjectionTyError::TraitSelectionError(Overflow));
+ report_overflow_error(selcx.infcx(), &obligation);
}
let obligation_trait_ref =
diff --git a/src/librustc/middle/traits/select.rs b/src/librustc/middle/traits/select.rs
index 7dfbccea0dccd..026ef7d4d0e44 100644
--- a/src/librustc/middle/traits/select.rs
+++ b/src/librustc/middle/traits/select.rs
@@ -21,8 +21,9 @@ use super::DerivedObligationCause;
use super::project;
use super::project::{normalize_with_depth, Normalized};
use super::{PredicateObligation, TraitObligation, ObligationCause};
+use super::{report_overflow_error};
use super::{ObligationCauseCode, BuiltinDerivedObligation, ImplDerivedObligation};
-use super::{SelectionError, Unimplemented, Overflow, OutputTypeParameterMismatch};
+use super::{SelectionError, Unimplemented, OutputTypeParameterMismatch};
use super::{Selection};
use super::{SelectionResult};
use super::{VtableBuiltin, VtableImpl, VtableParam, VtableClosure,
@@ -561,10 +562,7 @@ impl<'cx, 'tcx> SelectionContext<'cx, 'tcx> {
// not update) the cache.
let recursion_limit = self.infcx.tcx.sess.recursion_limit.get();
if stack.obligation.recursion_depth >= recursion_limit {
- debug!("{} --> overflow (limit={})",
- stack.obligation.repr(self.tcx()),
- recursion_limit);
- return Err(Overflow)
+ report_overflow_error(self.infcx(), &stack.obligation);
}
// Check the cache. Note that we skolemize the trait-ref
@@ -2582,11 +2580,13 @@ impl<'o, 'tcx> Repr<'tcx> for TraitObligationStack<'o, 'tcx> {
impl<'tcx> EvaluationResult<'tcx> {
fn may_apply(&self) -> bool {
match *self {
- EvaluatedToOk
- | EvaluatedToAmbig
- | EvaluatedToErr(Overflow)
- | EvaluatedToErr(OutputTypeParameterMismatch(..)) => true,
- EvaluatedToErr(Unimplemented) => false,
+ EvaluatedToOk |
+ EvaluatedToAmbig |
+ EvaluatedToErr(OutputTypeParameterMismatch(..)) =>
+ true,
+
+ EvaluatedToErr(Unimplemented) =>
+ false,
}
}
}
diff --git a/src/librustc/middle/traits/util.rs b/src/librustc/middle/traits/util.rs
index 88b721ce95862..965aaf12044ec 100644
--- a/src/librustc/middle/traits/util.rs
+++ b/src/librustc/middle/traits/util.rs
@@ -514,9 +514,6 @@ impl<'tcx> Repr<'tcx> for super::VtableObjectData<'tcx> {
impl<'tcx> Repr<'tcx> for super::SelectionError<'tcx> {
fn repr(&self, tcx: &ty::ctxt<'tcx>) -> String {
match *self {
- super::Overflow =>
- format!("Overflow"),
-
super::Unimplemented =>
format!("Unimplemented"),
diff --git a/src/librustc_trans/trans/common.rs b/src/librustc_trans/trans/common.rs
index 8f5dbfe2ec000..69846d4f0e4e4 100644
--- a/src/librustc_trans/trans/common.rs
+++ b/src/librustc_trans/trans/common.rs
@@ -1025,8 +1025,9 @@ pub fn fulfill_obligation<'a, 'tcx>(ccx: &CrateContext<'a, 'tcx>,
// shallow result we are looking for -- that is, what specific impl.
let typer = NormalizingClosureTyper::new(tcx);
let mut selcx = traits::SelectionContext::new(&infcx, &typer);
- let obligation = traits::Obligation::new(traits::ObligationCause::dummy(),
- trait_ref.to_poly_trait_predicate());
+ let obligation =
+ traits::Obligation::new(traits::ObligationCause::misc(span, ast::DUMMY_NODE_ID),
+ trait_ref.to_poly_trait_predicate());
let selection = match selcx.select(&obligation) {
Ok(Some(selection)) => selection,
Ok(None) => {
@@ -1081,7 +1082,7 @@ pub fn predicates_hold<'a, 'tcx>(ccx: &CrateContext<'a, 'tcx>,
let obligation = traits::Obligation::new(traits::ObligationCause::dummy(), predicate);
fulfill_cx.register_predicate_obligation(&infcx, obligation);
}
- drain_fulfillment_cx(DUMMY_SP, &infcx, &mut fulfill_cx, &()).is_ok()
+ drain_fulfillment_cx(&infcx, &mut fulfill_cx, &()).is_ok()
}
pub struct NormalizingClosureTyper<'a,'tcx:'a> {
@@ -1138,7 +1139,7 @@ pub fn drain_fulfillment_cx_or_panic<'a,'tcx,T>(span: Span,
-> T
where T : TypeFoldable<'tcx> + Repr<'tcx>
{
- match drain_fulfillment_cx(span, infcx, fulfill_cx, result) {
+ match drain_fulfillment_cx(infcx, fulfill_cx, result) {
Ok(v) => v,
Err(errors) => {
infcx.tcx.sess.span_bug(
@@ -1156,8 +1157,7 @@ pub fn drain_fulfillment_cx_or_panic<'a,'tcx,T>(span: Span,
/// inference variables that appear in `result` to be unified, and
/// hence we need to process those obligations to get the complete
/// picture of the type.
-pub fn drain_fulfillment_cx<'a,'tcx,T>(span: Span,
- infcx: &infer::InferCtxt<'a,'tcx>,
+pub fn drain_fulfillment_cx<'a,'tcx,T>(infcx: &infer::InferCtxt<'a,'tcx>,
fulfill_cx: &mut traits::FulfillmentContext<'tcx>,
result: &T)
-> StdResult<T,Vec<traits::FulfillmentError<'tcx>>>
@@ -1173,14 +1173,7 @@ pub fn drain_fulfillment_cx<'a,'tcx,T>(span: Span,
match fulfill_cx.select_all_or_error(infcx, &typer) {
Ok(()) => { }
Err(errors) => {
- // We always want to surface any overflow errors, no matter what.
- if errors.iter().all(|e| e.is_overflow()) {
- infcx.tcx.sess.span_fatal(
- span,
- "reached the recursion limit during monomorphization");
- } else {
- return Err(errors);
- }
+ return Err(errors);
}
}
diff --git a/src/test/compile-fail/issue-18400.rs b/src/test/compile-fail/issue-18400.rs
index 015f1fa603a20..f8d85f939374d 100644
--- a/src/test/compile-fail/issue-18400.rs
+++ b/src/test/compile-fail/issue-18400.rs
@@ -33,7 +33,4 @@ fn main() {
0.contains(bits);
//~^ ERROR overflow
- //~| ERROR overflow
- //~| ERROR overflow
- //~| ERROR mismatched types
}
diff --git a/src/test/compile-fail/recursion_limit.rs b/src/test/compile-fail/recursion_limit.rs
index e8bc11317f2aa..368269999a296 100644
--- a/src/test/compile-fail/recursion_limit.rs
+++ b/src/test/compile-fail/recursion_limit.rs
@@ -42,12 +42,5 @@ fn is_send<T:Send>() { }
fn main() {
is_send::<A>();
//~^ ERROR overflow evaluating
- //~^^ NOTE consider adding a `#![recursion_limit="20"]` attribute to your crate
- //~^^^ NOTE required by `is_send`
- //~^^^^ ERROR overflow evaluating
- //~^^^^^ NOTE consider adding a `#![recursion_limit="20"]` attribute to your crate
- //~^^^^^^ NOTE required by `is_send`
- //~^^^^^^^ ERROR overflow evaluating
- //~^^^^^^^^ NOTE consider adding a `#![recursion_limit="20"]` attribute to your crate
- //~^^^^^^^^^ NOTE required by `is_send`
+ //~| NOTE consider adding a `#![recursion_limit="20"]` attribute to your crate
}