Handle const generics elsewhere

Co-Authored-By: Gabriel Smith <yodaldevoid@users.noreply.github.com>

7 files changed, 28 insertions, 9 deletions

diff --git a/src/librustc/middle/resolve_lifetime.rs b/src/librustc/middle/resolve_lifetime.rs
index 2618d0874cb..d2bec1070f9 100644
--- a/src/librustc/middle/resolve_lifetime.rs
+++ b/src/librustc/middle/resolve_lifetime.rs
@@ -1974,7 +1974,7 @@ impl<'a, 'tcx> LifetimeContext<'a, 'tcx> {
                                     object_lifetime_default,
                                     ..
                                 } => Some(object_lifetime_default),
-                                GenericParamDefKind::Lifetime => None,
+                                GenericParamDefKind::Lifetime | GenericParamDefKind::Const => None,
                             })
                             .collect()
                     })
diff --git a/src/librustc/traits/error_reporting.rs b/src/librustc/traits/error_reporting.rs
index 3eb49092fed..322e384e13e 100644
--- a/src/librustc/traits/error_reporting.rs
+++ b/src/librustc/traits/error_reporting.rs
@@ -389,7 +389,8 @@ impl<'a, 'gcx, 'tcx> InferCtxt<'a, 'gcx, 'tcx> {
 
         for param in generics.params.iter() {
             let value = match param.kind {
-                GenericParamDefKind::Type {..} => {
+                GenericParamDefKind::Type { .. } |
+                GenericParamDefKind::Const => {
                     trait_ref.substs[param.index as usize].to_string()
                 },
                 GenericParamDefKind::Lifetime => continue,
diff --git a/src/librustc/traits/mod.rs b/src/librustc/traits/mod.rs
index ee7893a27de..32bb7f18693 100644
--- a/src/librustc/traits/mod.rs
+++ b/src/librustc/traits/mod.rs
@@ -1010,7 +1010,8 @@ fn vtable_methods<'a, 'tcx>(
                     InternalSubsts::for_item(tcx, def_id, |param, _|
                         match param.kind {
                             GenericParamDefKind::Lifetime => tcx.types.re_erased.into(),
-                            GenericParamDefKind::Type {..} => {
+                            GenericParamDefKind::Type { .. } |
+                            GenericParamDefKind::Const => {
                                 trait_ref.substs[param.index as usize]
                             }
                         }
diff --git a/src/librustc/traits/object_safety.rs b/src/librustc/traits/object_safety.rs
index b2079c25169..e7a5138e689 100644
--- a/src/librustc/traits/object_safety.rs
+++ b/src/librustc/traits/object_safety.rs
@@ -310,7 +310,8 @@ impl<'a, 'tcx> TyCtxt<'a, 'tcx, 'tcx> {
         }
 
         // We can't monomorphize things like `fn foo<A>(...)`.
-        if self.generics_of(method.def_id).own_counts().types != 0 {
+        let own_counts = self.generics_of(method.def_id).own_counts();
+        if own_counts.types + own_counts.consts != 0 {
             return Some(MethodViolationCode::Generic);
         }
 
diff --git a/src/librustc/traits/on_unimplemented.rs b/src/librustc/traits/on_unimplemented.rs
index f61c32614cc..c86fd0d52b9 100644
--- a/src/librustc/traits/on_unimplemented.rs
+++ b/src/librustc/traits/on_unimplemented.rs
@@ -280,7 +280,8 @@ impl<'a, 'gcx, 'tcx> OnUnimplementedFormatString {
         let generics = tcx.generics_of(trait_ref.def_id);
         let generic_map = generics.params.iter().filter_map(|param| {
             let value = match param.kind {
-                GenericParamDefKind::Type {..} => {
+                GenericParamDefKind::Type { .. } |
+                GenericParamDefKind::Const => {
                     trait_ref.substs[param.index as usize].to_string()
                 },
                 GenericParamDefKind::Lifetime => return None
diff --git a/src/librustc/ty/relate.rs b/src/librustc/ty/relate.rs
index 2940757fa90..3a31801b3be 100644
--- a/src/librustc/ty/relate.rs
+++ b/src/librustc/ty/relate.rs
@@ -705,6 +705,9 @@ impl<'tcx> Relate<'tcx> for Kind<'tcx> {
             (UnpackedKind::Type(unpacked), x) => {
                 bug!("impossible case reached: can't relate: {:?} with {:?}", unpacked, x)
             }
+            (UnpackedKind::Const(_), _) => {
+                unimplemented!() // FIXME(const_generics)
+            }
         }
     }
 }
diff --git a/src/librustc/ty/util.rs b/src/librustc/ty/util.rs
index 4ad3ffaa93d..fb0d1e2080b 100644
--- a/src/librustc/ty/util.rs
+++ b/src/librustc/ty/util.rs
@@ -12,6 +12,7 @@ use crate::ty::subst::{Subst, InternalSubsts, SubstsRef, UnpackedKind};
 use crate::ty::query::TyCtxtAt;
 use crate::ty::TyKind::*;
 use crate::ty::layout::{Integer, IntegerExt};
+use crate::mir::interpret::ConstValue;
 use crate::util::common::ErrorReported;
 use crate::middle::lang_items;
 
@@ -495,8 +496,16 @@ impl<'a, 'gcx, 'tcx> TyCtxt<'a, 'gcx, 'tcx> {
                     }) => {
                         !impl_generics.type_param(pt, self).pure_wrt_drop
                     }
-                    UnpackedKind::Lifetime(_) | UnpackedKind::Type(_) => {
-                        // not a type or region param - this should be reported
+                    UnpackedKind::Const(&ty::LazyConst::Evaluated(ty::Const {
+                        val: ConstValue::Param(ref pc),
+                        ..
+                    })) => {
+                        !impl_generics.const_param(pc, self).pure_wrt_drop
+                    }
+                    UnpackedKind::Lifetime(_) |
+                    UnpackedKind::Type(_) |
+                    UnpackedKind::Const(_) => {
+                        // Not a type, const or region param: this should be reported
                         // as an error.
                         false
                     }
@@ -587,15 +596,18 @@ impl<'a, 'gcx, 'tcx> TyCtxt<'a, 'gcx, 'tcx> {
         Some(ty::Binder::bind(env_ty))
     }
 
-    /// Given the `DefId` of some item that has no type parameters, make
+    /// Given the `DefId` of some item that has no type or const parameters, make
     /// a suitable "empty substs" for it.
     pub fn empty_substs_for_def_id(self, item_def_id: DefId) -> SubstsRef<'tcx> {
         InternalSubsts::for_item(self, item_def_id, |param, _| {
             match param.kind {
                 GenericParamDefKind::Lifetime => self.types.re_erased.into(),
-                GenericParamDefKind::Type {..} => {
+                GenericParamDefKind::Type { .. } => {
                     bug!("empty_substs_for_def_id: {:?} has type parameters", item_def_id)
                 }
+                GenericParamDefKind::Const { .. } => {
+                    bug!("empty_substs_for_def_id: {:?} has const parameters", item_def_id)
+                }
             }
         })
     }