Generalize a condition to allow _OptionalNilComparisonType. We now diagnose all of

the cases the hack Mark reverted used to (and more).

Author: lattner

lib/Sema/MiscDiagnostics.cpp

@@ -615,8 +615,7 @@ static void diagSyntacticUseRestrictions(TypeChecker &TC, const Expr *E,
     ///       (declref_expr implicit decl=Optional.init(nilLiteral:)
     static bool isTypeCheckedOptionalNil(Expr *E) {
       auto CE = dyn_cast<CallExpr>(E->getSemanticsProvidingExpr());
-      if (!CE || !CE->isImplicit() ||
-          !CE->getType()->getAnyOptionalObjectType())
+      if (!CE || !CE->isImplicit())
         return false;
 
       auto CRCE = dyn_cast<ConstructorRefCallExpr>(CE->getSemanticFn());

test/ClangModules/nullability.swift

@@ -7,11 +7,11 @@ import CoreCooling
 func testSomeClass(_ sc: SomeClass, osc: SomeClass?) {
   let ao1: AnyObject = sc.methodA(osc)
   _ = ao1
-  if sc.methodA(osc) == nil { }
+  if sc.methodA(osc) == nil { } // expected-warning {{comparing non-optional value of type 'AnyObject' to nil always returns false}}
 
   let ao2: AnyObject = sc.methodB(nil)
   _ = ao2
-  if sc.methodA(osc) == nil { }
+  if sc.methodA(osc) == nil { }// expected-warning {{comparing non-optional value of type 'AnyObject' to nil always returns false}}
 
   let ao3: AnyObject = sc.property // expected-error{{value of optional type 'AnyObject?' not unwrapped; did you mean to use '!' or '?'?}} {{35-35=!}}
   _ = ao3
@@ -20,7 +20,7 @@ func testSomeClass(_ sc: SomeClass, osc: SomeClass?) {
 
   let ao4: AnyObject = sc.methodD()
   _ = ao4
-  if sc.methodD() == nil { }
+  if sc.methodD() == nil { } // expected-warning {{comparing non-optional value of type 'AnyObject' to nil always returns false}}
 
   sc.methodE(sc)
   sc.methodE(osc) // expected-error{{value of optional type 'SomeClass?' not unwrapped; did you mean to use '!' or '?'?}} {{17-17=!}}
@@ -37,7 +37,7 @@ func testSomeClass(_ sc: SomeClass, osc: SomeClass?) {
   let sc2 = SomeClass(int: ci)
   let sc2a: SomeClass = sc2
   _ = sc2a
-  if sc2 == nil { }
+  if sc2 == nil { } // expected-warning {{comparing non-optional value of type 'SomeClass' to nil always returns false}}
 
   let sc3 = SomeClass(double: 1.5)
   if sc3 == nil { } // okay
@@ -47,7 +47,7 @@ func testSomeClass(_ sc: SomeClass, osc: SomeClass?) {
   let sc4 = sc.returnMe()
   let sc4a: SomeClass = sc4
   _ = sc4a
-  if sc4 == nil { }
+  if sc4 == nil { } // expected-warning {{comparing non-optional value of type 'SomeClass' to nil always returns false}}
 }
 
 // Nullability with CF types.

test/Constraints/diagnostics.swift

@@ -591,7 +591,7 @@ func r21684487() {
 func r18397777(_ d : r21447318?) {
   let c = r21447318()
 
-  if c != nil {
+  if c != nil { // expected-warning {{comparing non-optional value of type 'r21447318' to nil always returns true}}
   }
 
   if d {  // expected-error {{optional type 'r21447318?' cannot be used as a boolean; test for '!= nil' instead}} {{6-6=(}} {{7-7= != nil)}}