From 638d1d34ff89803b8558713fa6d5dff79019c854 Mon Sep 17 00:00:00 2001
From: varkor <github@varkor.com>
Date: Mon, 6 May 2019 13:54:59 +0100
Subject: [PATCH 1/8] Remove duplicate comment
Co-Authored-By: Gabriel Smith <yodaldevoid@users.noreply.github.com>
---
src/libsyntax/parse/parser.rs | 4 ----
1 file changed, 4 deletions(-)
diff --git a/src/libsyntax/parse/parser.rs b/src/libsyntax/parse/parser.rs
index d46feeab33599..084091f4c2a39 100644
--- a/src/libsyntax/parse/parser.rs
+++ b/src/libsyntax/parse/parser.rs
@@ -6045,10 +6045,6 @@ impl<'a> Parser<'a> {
});
assoc_ty_bindings.push(span);
} else if self.check_const_arg() {
- // FIXME(const_generics): to distinguish between idents for types and consts,
- // we should introduce a GenericArg::Ident in the AST and distinguish when
- // lowering to the HIR. For now, idents for const args are not permitted.
-
// Parse const argument.
let expr = if let token::OpenDelim(token::Brace) = self.token {
self.parse_block_expr(None, self.span, BlockCheckMode::Default, ThinVec::new())?
From 59ebd1b7c2b9558ab31c57878666f0707f33b689 Mon Sep 17 00:00:00 2001
From: varkor <github@varkor.com>
Date: Mon, 6 May 2019 13:55:14 +0100
Subject: [PATCH 2/8] Shift const vars through binders
Co-Authored-By: Gabriel Smith <yodaldevoid@users.noreply.github.com>
---
src/librustc/ty/subst.rs | 15 +++++++--------
1 file changed, 7 insertions(+), 8 deletions(-)
diff --git a/src/librustc/ty/subst.rs b/src/librustc/ty/subst.rs
index 8d51fbc174a04..e5bd3f15efe95 100644
--- a/src/librustc/ty/subst.rs
+++ b/src/librustc/ty/subst.rs
@@ -618,8 +618,7 @@ impl<'a, 'gcx, 'tcx> SubstFolder<'a, 'gcx, 'tcx> {
}
};
- // FIXME(const_generics): shift const through binders
- ct
+ self.shift_vars_through_binders(ct)
}
/// It is sometimes necessary to adjust the De Bruijn indices during substitution. This occurs
@@ -664,15 +663,15 @@ impl<'a, 'gcx, 'tcx> SubstFolder<'a, 'gcx, 'tcx> {
/// As indicated in the diagram, here the same type `&'a int` is substituted once, but in the
/// first case we do not increase the De Bruijn index and in the second case we do. The reason
/// is that only in the second case have we passed through a fn binder.
- fn shift_vars_through_binders(&self, ty: Ty<'tcx>) -> Ty<'tcx> {
- debug!("shift_vars(ty={:?}, binders_passed={:?}, has_escaping_bound_vars={:?})",
- ty, self.binders_passed, ty.has_escaping_bound_vars());
+ fn shift_vars_through_binders<T: TypeFoldable<'tcx>>(&self, val: T) -> T {
+ debug!("shift_vars(val={:?}, binders_passed={:?}, has_escaping_bound_vars={:?})",
+ val, self.binders_passed, val.has_escaping_bound_vars());
- if self.binders_passed == 0 || !ty.has_escaping_bound_vars() {
- return ty;
+ if self.binders_passed == 0 || !val.has_escaping_bound_vars() {
+ return val;
}
- let result = ty::fold::shift_vars(self.tcx(), &ty, self.binders_passed);
+ let result = ty::fold::shift_vars(self.tcx(), &val, self.binders_passed);
debug!("shift_vars: shifted result = {:?}", result);
result
From ad78fcf5246c9accb2a35ced91d85b710648abc9 Mon Sep 17 00:00:00 2001
From: varkor <github@varkor.com>
Date: Mon, 6 May 2019 13:55:28 +0100
Subject: [PATCH 3/8] Ignore const parameters when constructing type bounds in
rustdoc
Co-Authored-By: Gabriel Smith <yodaldevoid@users.noreply.github.com>
---
src/librustdoc/clean/mod.rs | 4 +---
1 file changed, 1 insertion(+), 3 deletions(-)
diff --git a/src/librustdoc/clean/mod.rs b/src/librustdoc/clean/mod.rs
index de74a6a540055..3a260db806520 100644
--- a/src/librustdoc/clean/mod.rs
+++ b/src/librustdoc/clean/mod.rs
@@ -1706,9 +1706,7 @@ impl<'a, 'tcx> Clean<Generics> for (&'a ty::Generics,
}
Some(param.clean(cx))
}
- ty::GenericParamDefKind::Const { .. } => {
- unimplemented!() // FIXME(const_generics)
- }
+ ty::GenericParamDefKind::Const { .. } => None,
}).collect::<Vec<GenericParamDef>>();
let mut where_predicates = preds.predicates.iter()
From c6197541f73c570f5104c36920b387992c7658d2 Mon Sep 17 00:00:00 2001
From: varkor <github@varkor.com>
Date: Mon, 6 May 2019 14:05:26 +0100
Subject: [PATCH 4/8] Implement TypeFoldable for InferConst
Co-Authored-By: Gabriel Smith <yodaldevoid@users.noreply.github.com>
---
src/librustc/ty/structural_impls.rs | 18 +++++++++++++-----
1 file changed, 13 insertions(+), 5 deletions(-)
diff --git a/src/librustc/ty/structural_impls.rs b/src/librustc/ty/structural_impls.rs
index bab9527dd07f6..f81394a878f5a 100644
--- a/src/librustc/ty/structural_impls.rs
+++ b/src/librustc/ty/structural_impls.rs
@@ -6,7 +6,7 @@
use crate::hir::def::Namespace;
use crate::mir::ProjectionKind;
use crate::mir::interpret::ConstValue;
-use crate::ty::{self, Lift, Ty, TyCtxt, ConstVid};
+use crate::ty::{self, Lift, Ty, TyCtxt, ConstVid, InferConst};
use crate::ty::fold::{TypeFoldable, TypeFolder, TypeVisitor};
use crate::ty::print::{FmtPrinter, Printer};
use rustc_data_structures::indexed_vec::{IndexVec, Idx};
@@ -1352,8 +1352,7 @@ impl<'tcx> TypeFoldable<'tcx> for ConstValue<'tcx> {
fn super_fold_with<'gcx: 'tcx, F: TypeFolder<'gcx, 'tcx>>(&self, folder: &mut F) -> Self {
match *self {
ConstValue::ByRef(ptr, alloc) => ConstValue::ByRef(ptr, alloc),
- // FIXME(const_generics): implement TypeFoldable for InferConst
- ConstValue::Infer(ic) => ConstValue::Infer(ic),
+ ConstValue::Infer(ic) => ConstValue::Infer(ic.fold_with(folder)),
ConstValue::Param(p) => ConstValue::Param(p.fold_with(folder)),
ConstValue::Placeholder(p) => ConstValue::Placeholder(p),
ConstValue::Scalar(a) => ConstValue::Scalar(a),
@@ -1366,8 +1365,7 @@ impl<'tcx> TypeFoldable<'tcx> for ConstValue<'tcx> {
fn super_visit_with<V: TypeVisitor<'tcx>>(&self, visitor: &mut V) -> bool {
match *self {
ConstValue::ByRef(..) => false,
- // FIXME(const_generics): implement TypeFoldable for InferConst
- ConstValue::Infer(_) => false,
+ ConstValue::Infer(ic) => ic.visit_with(visitor),
ConstValue::Param(p) => p.visit_with(visitor),
ConstValue::Placeholder(_) => false,
ConstValue::Scalar(_) => false,
@@ -1376,3 +1374,13 @@ impl<'tcx> TypeFoldable<'tcx> for ConstValue<'tcx> {
}
}
}
+
+impl<'tcx> TypeFoldable<'tcx> for InferConst<'tcx> {
+ fn super_fold_with<'gcx: 'tcx, F: TypeFolder<'gcx, 'tcx>>(&self, _folder: &mut F) -> Self {
+ *self
+ }
+
+ fn super_visit_with<V: TypeVisitor<'tcx>>(&self, _visitor: &mut V) -> bool {
+ false
+ }
+}
From 670cf11de22583e1192636f0e6c36007ebcbb776 Mon Sep 17 00:00:00 2001
From: varkor <github@varkor.com>
Date: Mon, 6 May 2019 14:16:07 +0100
Subject: [PATCH 5/8] Clean up `push_const_name`
Co-Authored-By: Gabriel Smith <yodaldevoid@users.noreply.github.com>
---
src/librustc_mir/monomorphize/item.rs | 40 +++++++++++++++++----------
1 file changed, 26 insertions(+), 14 deletions(-)
diff --git a/src/librustc_mir/monomorphize/item.rs b/src/librustc_mir/monomorphize/item.rs
index b001a09529e5b..999e7402afd93 100644
--- a/src/librustc_mir/monomorphize/item.rs
+++ b/src/librustc_mir/monomorphize/item.rs
@@ -3,7 +3,7 @@ use rustc::hir;
use rustc::hir::def_id::{DefId, LOCAL_CRATE};
use rustc::mir::interpret::ConstValue;
use rustc::session::config::OptLevel;
-use rustc::ty::{self, Ty, TyCtxt, Const, ClosureSubsts, GeneratorSubsts, ParamConst};
+use rustc::ty::{self, Ty, TyCtxt, Const, ClosureSubsts, GeneratorSubsts};
use rustc::ty::subst::{SubstsRef, InternalSubsts};
use syntax::ast;
use syntax::attr::InlineAttr;
@@ -240,11 +240,11 @@ impl<'a, 'tcx> DefPathBasedNames<'a, 'tcx> {
}
// Pushes the type name of the specified type to the provided string.
- // If 'debug' is true, printing normally unprintable types is allowed
- // (e.g. ty::GeneratorWitness). This parameter should only be set when
- // this method is being used for logging purposes (e.g. with debug! or info!)
- // When being used for codegen purposes, 'debug' should be set to 'false'
- // in order to catch unexpected types that should never end up in a type name
+ // If `debug` is true, printing normally unprintable types is allowed
+ // (e.g. `ty::GeneratorWitness`). This parameter should only be set when
+ // this method is being used for logging purposes (e.g. with `debug!` or `info!`)
+ // When being used for codegen purposes, `debug` should be set to `false`
+ // in order to catch unexpected types that should never end up in a type name.
pub fn push_type_name(&self, t: Ty<'tcx>, output: &mut String, debug: bool) {
match t.sty {
ty::Bool => output.push_str("bool"),
@@ -387,22 +387,34 @@ impl<'a, 'tcx> DefPathBasedNames<'a, 'tcx> {
if debug {
output.push_str(&format!("`{:?}`", t));
} else {
- bug!("DefPathBasedNames: Trying to create type name for \
- unexpected type: {:?}", t);
+ bug!(
+ "DefPathBasedNames: trying to create type name for unexpected type: {:?}",
+ t,
+ );
}
}
}
}
- // FIXME(const_generics): handle debug printing.
+ // Pushes the the name of the specified const to the provided string.
+ // If `debug` is true, usually-unprintable consts (such as `Infer`) will be printed,
+ // as well as the unprintable types of constants (see `push_type_name` for more details).
pub fn push_const_name(&self, c: &Const<'tcx>, output: &mut String, debug: bool) {
match c.val {
- ConstValue::Infer(..) | ConstValue::Placeholder(_) => output.push_str("_"),
- ConstValue::Param(ParamConst { name, .. }) => {
- write!(output, "{}", name).unwrap();
+ ConstValue::Scalar(..) | ConstValue::Slice(..) | ConstValue::ByRef(..) => {
+ // FIXME(const_generics): we could probably do a better job here.
+ write!(output, "{:?}", c).unwrap()
+ }
+ _ => {
+ if debug {
+ write!(output, "{:?}", c).unwrap()
+ } else {
+ bug!(
+ "DefPathBasedNames: trying to create const name for unexpected const: {:?}",
+ c,
+ );
+ }
}
- ConstValue::Unevaluated(..) => output.push_str("_: _"),
- _ => write!(output, "{:?}", c).unwrap(),
}
output.push_str(": ");
self.push_type_name(c.ty, output, debug);
From c0454f0638f235dd7c8b4bb57ea5614e5e877746 Mon Sep 17 00:00:00 2001
From: varkor <github@varkor.com>
Date: Mon, 6 May 2019 14:16:28 +0100
Subject: [PATCH 6/8] Remove incorrect FIXME
Co-Authored-By: Gabriel Smith <yodaldevoid@users.noreply.github.com>
---
src/librustc_typeck/check/mod.rs | 2 --
1 file changed, 2 deletions(-)
diff --git a/src/librustc_typeck/check/mod.rs b/src/librustc_typeck/check/mod.rs
index e404a8e6972c8..82fcf8ff52f83 100644
--- a/src/librustc_typeck/check/mod.rs
+++ b/src/librustc_typeck/check/mod.rs
@@ -5785,8 +5785,6 @@ pub fn check_bounds_are_used<'a, 'tcx>(tcx: TyCtxt<'a, 'tcx, 'tcx>,
ty
);
- // FIXME(const_generics): we probably want to check the bounds for const parameters too.
-
if own_counts.types == 0 {
return;
}
From 5fc0395053c732c8becf0e1dca7000554c352ccd Mon Sep 17 00:00:00 2001
From: varkor <github@varkor.com>
Date: Mon, 6 May 2019 14:17:48 +0100
Subject: [PATCH 7/8] Resolve a couple of `unimplemented!()`s
Co-Authored-By: Gabriel Smith <yodaldevoid@users.noreply.github.com>
---
src/librustc/infer/canonical/query_response.rs | 10 ++++++----
1 file changed, 6 insertions(+), 4 deletions(-)
diff --git a/src/librustc/infer/canonical/query_response.rs b/src/librustc/infer/canonical/query_response.rs
index 8225ed70c5827..413c1428ff954 100644
--- a/src/librustc/infer/canonical/query_response.rs
+++ b/src/librustc/infer/canonical/query_response.rs
@@ -318,8 +318,9 @@ impl<'cx, 'gcx, 'tcx> InferCtxt<'cx, 'gcx, 'tcx> {
obligations.extend(ok.into_obligations());
}
- (UnpackedKind::Const(..), UnpackedKind::Const(..)) => {
- unimplemented!() // FIXME(const_generics)
+ (UnpackedKind::Const(v1), UnpackedKind::Const(v2)) => {
+ let ok = self.at(cause, param_env).eq(v1, v2)?;
+ obligations.extend(ok.into_obligations());
}
_ => {
@@ -626,8 +627,9 @@ impl<'cx, 'gcx, 'tcx> InferCtxt<'cx, 'gcx, 'tcx> {
obligations
.extend(self.at(cause, param_env).eq(v1, v2)?.into_obligations());
}
- (UnpackedKind::Const(..), UnpackedKind::Const(..)) => {
- unimplemented!() // FIXME(const_generics)
+ (UnpackedKind::Const(v1), UnpackedKind::Const(v2)) => {
+ let ok = self.at(cause, param_env).eq(v1, v2)?;
+ obligations.extend(ok.into_obligations());
}
_ => {
bug!("kind mismatch, cannot unify {:?} and {:?}", value1, value2,);
From 9a2772aff0e6c2058fb52a844b4593eabd18fcbc Mon Sep 17 00:00:00 2001
From: varkor <github@varkor.com>
Date: Mon, 6 May 2019 15:07:46 +0100
Subject: [PATCH 8/8] Implement `ToTrace` for `ty::Const`
---
src/librustc/infer/at.rs | 15 +++++++++++++++
src/librustc/infer/error_reporting/mod.rs | 1 +
src/librustc/infer/mod.rs | 2 ++
3 files changed, 18 insertions(+)
diff --git a/src/librustc/infer/at.rs b/src/librustc/infer/at.rs
index 34cd3ae5427e0..5772110889290 100644
--- a/src/librustc/infer/at.rs
+++ b/src/librustc/infer/at.rs
@@ -27,6 +27,7 @@
use super::*;
+use crate::ty::Const;
use crate::ty::relate::{Relate, TypeRelation};
pub struct At<'a, 'gcx: 'tcx, 'tcx: 'a> {
@@ -308,6 +309,20 @@ impl<'tcx> ToTrace<'tcx> for ty::Region<'tcx> {
}
}
+impl<'tcx> ToTrace<'tcx> for &'tcx Const<'tcx> {
+ fn to_trace(cause: &ObligationCause<'tcx>,
+ a_is_expected: bool,
+ a: Self,
+ b: Self)
+ -> TypeTrace<'tcx>
+ {
+ TypeTrace {
+ cause: cause.clone(),
+ values: Consts(ExpectedFound::new(a_is_expected, a, b))
+ }
+ }
+}
+
impl<'tcx> ToTrace<'tcx> for ty::TraitRef<'tcx> {
fn to_trace(cause: &ObligationCause<'tcx>,
a_is_expected: bool,
diff --git a/src/librustc/infer/error_reporting/mod.rs b/src/librustc/infer/error_reporting/mod.rs
index 95b566d4a1b69..4b6e7da333081 100644
--- a/src/librustc/infer/error_reporting/mod.rs
+++ b/src/librustc/infer/error_reporting/mod.rs
@@ -1260,6 +1260,7 @@ impl<'a, 'gcx, 'tcx> InferCtxt<'a, 'gcx, 'tcx> {
match *values {
infer::Types(ref exp_found) => self.expected_found_str_ty(exp_found),
infer::Regions(ref exp_found) => self.expected_found_str(exp_found),
+ infer::Consts(ref exp_found) => self.expected_found_str(exp_found),
infer::TraitRefs(ref exp_found) => self.expected_found_str(exp_found),
infer::PolyTraitRefs(ref exp_found) => self.expected_found_str(exp_found),
}
diff --git a/src/librustc/infer/mod.rs b/src/librustc/infer/mod.rs
index 5846e604cfc09..b5a9184079aa6 100644
--- a/src/librustc/infer/mod.rs
+++ b/src/librustc/infer/mod.rs
@@ -232,6 +232,7 @@ pub type PlaceholderMap<'tcx> = BTreeMap<ty::BoundRegion, ty::Region<'tcx>>;
pub enum ValuePairs<'tcx> {
Types(ExpectedFound<Ty<'tcx>>),
Regions(ExpectedFound<ty::Region<'tcx>>),
+ Consts(ExpectedFound<&'tcx ty::Const<'tcx>>),
TraitRefs(ExpectedFound<ty::TraitRef<'tcx>>),
PolyTraitRefs(ExpectedFound<ty::PolyTraitRef<'tcx>>),
}
@@ -1730,6 +1731,7 @@ EnumTypeFoldableImpl! {
impl<'tcx> TypeFoldable<'tcx> for ValuePairs<'tcx> {
(ValuePairs::Types)(a),
(ValuePairs::Regions)(a),
+ (ValuePairs::Consts)(a),
(ValuePairs::TraitRefs)(a),
(ValuePairs::PolyTraitRefs)(a),
}