Remove VarDecl::markInvalid

Inline the interface type reset into its callers and make sure they're
also setting the invalid bit - which this was not doing before.
Unfortunately, this is not enough to be able to simplify any part of var
decl validation.

Author: CodaFi

include/swift/AST/Decl.h

@@ -4809,8 +4809,6 @@ class VarDecl : public AbstractStorageDecl {
   /// this will use archetypes.
   Type getType() const;
 
-  void markInvalid();
-
   /// Retrieve the source range of the variable type, or an invalid range if the
   /// variable's type is not explicitly written in the source.
   ///

lib/AST/Decl.cpp

@@ -5010,10 +5010,6 @@ Type VarDecl::getType() const {
   return getDeclContext()->mapTypeIntoContext(getInterfaceType());
 }
 
-void VarDecl::markInvalid() {
-  setInterfaceType(ErrorType::get(getASTContext()));
-}
-
 /// Returns whether the var is settable in the specified context: this
 /// is either because it is a stored var, because it has a custom setter, or
 /// is a let member in an initializer.

lib/Sema/ConstraintSystem.cpp

@@ -823,7 +823,7 @@ Type ConstraintSystem::getUnopenedTypeOfReference(VarDecl *value, Type baseType,
           if (!var->isInvalid()) {
             TC.diagnose(var->getLoc(), diag::recursive_decl_reference,
                         var->getDescriptiveKind(), var->getName());
-            var->markInvalid();
+            var->setInterfaceType(ErrorType::get(getASTContext()));
           }
           return ErrorType::get(TC.Context);
         }

lib/Sema/TypeCheckConstraints.cpp

@@ -2824,7 +2824,7 @@ bool TypeChecker::typeCheckBinding(Pattern *&pattern, Expr *&initializer,
           !var->getType()->hasError())
         return;
 
-      var->markInvalid();
+      var->setInterfaceType(ErrorType::get(Context));
     });
   }
 
@@ -3033,7 +3033,7 @@ bool TypeChecker::typeCheckStmtCondition(StmtCondition &cond, DeclContext *dc,
         // compute a type for.
         if (var->hasInterfaceType() && !var->getType()->hasError())
           return;
-        var->markInvalid();
+        var->setInterfaceType(ErrorType::get(Context));
       });
     };
 

lib/Sema/TypeCheckDecl.cpp

@@ -2459,7 +2459,7 @@ class DeclChecker : public DeclVisitor<DeclChecker> {
         auto markVarAndPBDInvalid = [PBD, var] {
           PBD->setInvalid();
           var->setInvalid();
-          var->markInvalid();
+          var->setInterfaceType(ErrorType::get(var->getASTContext()));
         };
 
         // Properties with an opaque return type need an initializer to
@@ -4244,12 +4244,7 @@ void TypeChecker::validateDecl(ValueDecl *D) {
       if (!PBD->isBeingValidated()) {
         validatePatternBindingEntries(*this, PBD);
       } else if (!VD->getNamingPattern()) {
-        // FIXME: This acts as a circularity breaker for overload resolution
-        // during pattern binding validation, which is allowed to lookup and
-        // find the very VarDecl attached to the binding it's trying to check.
-        // In order to tell it to back off, we surface an error type but don't
-        // set the interface type so a different caller can come along and
-        // do the right thing.
+        // FIXME: This acts as a circularity breaker.
         return;
       }
 
@@ -4260,7 +4255,7 @@ void TypeChecker::validateDecl(ValueDecl *D) {
       }
     } else if (!VD->getParentPatternStmt() && !VD->getParentVarDecl()) {
       // No parent?  That's an error.
-      VD->markInvalid();
+      VD->setInterfaceType(ErrorType::get(Context));
       break;
     }
 
@@ -4283,7 +4278,7 @@ void TypeChecker::validateDecl(ValueDecl *D) {
 
         VD->getParentPattern()->setType(ErrorType::get(Context));
         setBoundVarsTypeError(VD->getParentPattern(), Context);
-        VD->markInvalid();
+        VD->setInterfaceType(ErrorType::get(Context));
         break;
       }
     }

lib/Sema/TypeCheckPattern.cpp

@@ -806,7 +806,8 @@ bool TypeChecker::typeCheckPattern(Pattern *P, DeclContext *dc,
     P->setType(ErrorType::get(Context));
     if (auto named = dyn_cast<NamedPattern>(P)) {
       if (auto var = named->getDecl()) {
-        var->markInvalid();
+        var->setInterfaceType(ErrorType::get(Context));
+        var->setInvalid();
       }
     }
     return true;

lib/Sema/TypeCheckStmt.cpp

@@ -1064,7 +1064,10 @@ class StmtChecker : public StmtVisitor<StmtChecker, Stmt*> {
 
       // If that failed, mark any variables binding pieces of the pattern
       // as invalid to silence follow-on errors.
-      pattern->forEachVariable([&](VarDecl *VD) { VD->markInvalid(); });
+      pattern->forEachVariable([&](VarDecl *VD) {
+        VD->setInterfaceType(ErrorType::get(TC.Context));
+        VD->setInvalid();
+      });
     }
     labelItem.setPattern(pattern);
 
@@ -1140,8 +1143,11 @@ class StmtChecker : public StmtVisitor<StmtChecker, Stmt*> {
             !vd->getType()->isEqual(initialCaseVarDecl->getType())) {
           TC.diagnose(vd->getLoc(), diag::type_mismatch_multiple_pattern_list,
                       vd->getType(), initialCaseVarDecl->getType());
-          vd->markInvalid();
-          initialCaseVarDecl->markInvalid();
+          vd->setInterfaceType(ErrorType::get(TC.Context));
+          vd->setInvalid();
+
+          initialCaseVarDecl->setInterfaceType(ErrorType::get(TC.Context));
+          initialCaseVarDecl->setInvalid();
         }
 
         if (initialCaseVarDecl->isLet() == vd->isLet()) {
@@ -1161,8 +1167,11 @@ class StmtChecker : public StmtVisitor<StmtChecker, Stmt*> {
         if (foundVP)
           diag.fixItReplace(foundVP->getLoc(),
                             initialCaseVarDecl->isLet() ? "let" : "var");
-        vd->markInvalid();
-        initialCaseVarDecl->markInvalid();
+        vd->setInterfaceType(ErrorType::get(TC.Context));
+        vd->setInvalid();
+
+        initialCaseVarDecl->setInterfaceType(ErrorType::get(TC.Context));
+        initialCaseVarDecl->setInvalid();
       }
     });
 
@@ -1229,8 +1238,11 @@ class StmtChecker : public StmtVisitor<StmtChecker, Stmt*> {
           TC.diagnose(previous->getLoc(),
                       diag::type_mismatch_fallthrough_pattern_list,
                       previous->getType(), expected->getType());
-          previous->markInvalid();
-          expected->markInvalid();
+          previous->setInterfaceType(ErrorType::get(TC.Context));
+          previous->setInvalid();
+
+          expected->setInterfaceType(ErrorType::get(TC.Context));
+          expected->setInvalid();
         }
 
         // Ok, we found our match. Make the previous fallthrough statement var
@@ -1465,7 +1477,8 @@ bool TypeChecker::typeCheckCatchPattern(CatchStmt *S, DeclContext *DC) {
       // before we type-check the guard.  (This will probably kill
       // most of the type-checking, but maybe not.)
       pattern->forEachVariable([&](VarDecl *var) {
-        var->markInvalid();
+        var->setInterfaceType(ErrorType::get(Context));
+        var->setInvalid();
       });
     }
 

lib/Sema/TypeCheckStorage.cpp

@@ -42,7 +42,8 @@ void swift::setBoundVarsTypeError(Pattern *pattern, ASTContext &ctx) {
     if (var->hasInterfaceType() && !var->getType()->hasError())
       return;
 
-    var->markInvalid();
+    var->setInterfaceType(ErrorType::get(var->getASTContext()));
+    var->setInvalid();
   });
 }