Sema: Don't trigger ImplInfoRequest from TypeChecker::buildRefExpr()

It's too early to do that here, because we may be building a reference
to a ParamDecl that is not yet known to be inout, because the constraint
solver has not run yet.

Instead, always compute the access semantics in CSApply.

Author: slavapestov

lib/Sema/CSApply.cpp

@@ -482,8 +482,7 @@ namespace {
   public:
     /// Build a reference to the given declaration.
     Expr *buildDeclRef(SelectedOverload overload, DeclNameLoc loc,
-                       ConstraintLocatorBuilder locator, bool implicit,
-                       AccessSemantics semantics) {
+                       ConstraintLocatorBuilder locator, bool implicit) {
       auto choice = overload.choice;
       assert(choice.getKind() != OverloadChoiceKind::DeclViaDynamic);
       auto *decl = choice.getDecl();
@@ -492,6 +491,9 @@ namespace {
       // Determine the declaration selected for this overloaded reference.
       auto &ctx = cs.getASTContext();
 
+      auto semantics = decl->getAccessSemanticsFromContext(cs.DC,
+                                                           /*isAccessOnSelf*/false);
+
       // If this is a member of a nominal type, build a reference to the
       // member with an implied base type.
       if (decl->getDeclContext()->isTypeContext() && isa<FuncDecl>(decl)) {
@@ -2686,7 +2688,7 @@ namespace {
       // Find the overload choice used for this declaration reference.
       auto selected = solution.getOverloadChoice(locator);
       return buildDeclRef(selected, expr->getNameLoc(), locator,
-                          expr->isImplicit(), expr->getAccessSemantics());
+                          expr->isImplicit());
     }
 
     Expr *visitSuperRefExpr(SuperRefExpr *expr) {
@@ -2716,7 +2718,7 @@ namespace {
       auto selected = solution.getOverloadChoice(locator);
 
       return buildDeclRef(selected, expr->getNameLoc(), locator,
-                          expr->isImplicit(), AccessSemantics::Ordinary);
+                          expr->isImplicit());
     }
 
     Expr *visitUnresolvedDeclRefExpr(UnresolvedDeclRefExpr *expr) {
@@ -3036,8 +3038,7 @@ namespace {
         diagnoseDeprecatedConditionalConformanceOuterAccess(
             UDE, selected.choice.getDecl());
 
-        return buildDeclRef(selected, nameLoc, memberLocator, implicit,
-                            AccessSemantics::Ordinary);
+        return buildDeclRef(selected, nameLoc, memberLocator, implicit);
       }
 
       switch (selected.choice.getKind()) {

lib/Sema/TypeCheckExpr.cpp

@@ -601,10 +601,10 @@ Expr *TypeChecker::buildRefExpr(ArrayRef<ValueDecl *> Decls,
   assert(!Decls.empty() && "Must have at least one declaration");
 
   auto &Context = UseDC->getASTContext();
-  if (Decls.size() == 1 && !isa<ProtocolDecl>(Decls[0]->getDeclContext())) {
-    auto semantics = Decls[0]->getAccessSemanticsFromContext(UseDC,
-                                                       /*isAccessOnSelf*/false);
-    return new (Context) DeclRefExpr(Decls[0], NameLoc, Implicit, semantics);
+
+  if (Decls.size() == 1) {
+    return new (Context) DeclRefExpr(Decls[0], NameLoc, Implicit,
+                                     AccessSemantics::Ordinary);
   }
 
   Decls = Context.AllocateCopy(Decls);