Auto merge of #46033 - sinkuu:const-enum-match-check, r=arielb1

Do match-check for consts

Fixes #43195 (ICE caused by building MIR that contains non-exausitive match)

src/librustc/dep_graph/dep_node.rs

@@ -516,6 +516,7 @@ define_dep_nodes!( <'tcx>
     [] UsedTraitImports(DefId),
     [] HasTypeckTables(DefId),
     [] ConstEval { param_env: ParamEnvAnd<'tcx, (DefId, &'tcx Substs<'tcx>)> },
+    [] CheckMatch(DefId),
     [] SymbolName(DefId),
     [] InstanceSymbolName { instance: Instance<'tcx> },
     [] SpecializationGraph(DefId),

src/librustc/ich/impls_ty.rs

@@ -371,7 +371,8 @@ for ::middle::const_val::ErrKind<'gcx> {
             MiscBinaryOp |
             MiscCatchAll |
             IndexOpFeatureGated |
-            TypeckError => {
+            TypeckError |
+            CheckMatchError => {
                 // nothing to do
             }
             UnimplementedConstVal(s) => {

src/librustc/middle/const_val.rs

@@ -106,7 +106,8 @@ pub enum ErrKind<'tcx> {
 
     ErroneousReferencedConstant(Box<ConstEvalErr<'tcx>>),
 
-    TypeckError
+    TypeckError,
+    CheckMatchError,
 }
 
 impl<'tcx> From<ConstMathErr> for ErrKind<'tcx> {
@@ -168,6 +169,7 @@ impl<'a, 'gcx, 'tcx> ConstEvalErr<'tcx> {
             ErroneousReferencedConstant(_) => simple!("could not evaluate referenced constant"),
 
             TypeckError => simple!("type-checking failed"),
+            CheckMatchError => simple!("match-checking failed"),
         }
     }
 
@@ -212,8 +214,9 @@ impl<'a, 'gcx, 'tcx> ConstEvalErr<'tcx> {
         primary_span: Span,
         primary_kind: &str)
     {
-        if let ErrKind::TypeckError = self.kind {
-            return;
+        match self.kind {
+            ErrKind::TypeckError | ErrKind::CheckMatchError => return,
+            _ => {}
         }
         self.struct_error(tcx, primary_span, primary_kind).emit();
     }

src/librustc/ty/maps/mod.rs

@@ -37,7 +37,7 @@ use ty::{self, CrateInherentImpls, Ty, TyCtxt};
 use ty::steal::Steal;
 use ty::subst::Substs;
 use util::nodemap::{DefIdSet, DefIdMap, ItemLocalSet};
-use util::common::{profq_msg, ProfileQueriesMsg};
+use util::common::{profq_msg, ErrorReported, ProfileQueriesMsg};
 
 use rustc_data_structures::indexed_set::IdxSetBuf;
 use rustc_back::PanicStrategy;
@@ -205,6 +205,9 @@ define_maps! { <'tcx>
     [] fn const_eval: const_eval_dep_node(ty::ParamEnvAnd<'tcx, (DefId, &'tcx Substs<'tcx>)>)
         -> const_val::EvalResult<'tcx>,
 
+    [] fn check_match: CheckMatch(DefId)
+        -> Result<(), ErrorReported>,
+
     /// Performs the privacy check and computes "access levels".
     [] fn privacy_access_levels: PrivacyAccessLevels(CrateNum) -> Rc<AccessLevels>,
 

src/librustc/ty/maps/plumbing.rs

@@ -800,6 +800,7 @@ pub fn force_from_dep_node<'a, 'gcx, 'lcx>(tcx: TyCtxt<'a, 'gcx, 'lcx>,
         DepKind::SpecializationGraph => { force!(specialization_graph_of, def_id!()); }
         DepKind::ObjectSafety => { force!(is_object_safe, def_id!()); }
         DepKind::TraitImpls => { force!(trait_impls_of, def_id!()); }
+        DepKind::CheckMatch => { force!(check_match, def_id!()); }
 
         DepKind::ParamEnv => { force!(param_env, def_id!()); }
         DepKind::DescribeDef => { force!(describe_def, def_id!()); }

src/librustc/ty/structural_impls.rs

@@ -477,6 +477,7 @@ impl<'a, 'tcx> Lift<'tcx> for const_val::ErrKind<'a> {
             }
 
             TypeckError => TypeckError,
+            CheckMatchError => CheckMatchError,
         })
     }
 }