Merge pull request swiftlang#21342 from slavapestov/trivial-tests-and-fixes

Trivial tests and a fix

Author: slavapestov

lib/SILGen/SILGenExpr.cpp

@@ -4283,9 +4283,6 @@ namespace {
 
     // If the destination is a tuple, recursively destructure.
     void visitTupleExpr(TupleExpr *E) {
-      auto *TTy = E->getType()->castTo<TupleType>();
-      assert(TTy->hasLValueType() || TTy->isVoid());
-      (void)TTy;
       for (auto &elt : E->getElements()) {
         visit(elt);
       }
@@ -4398,7 +4395,6 @@ static void emitSimpleAssignment(SILGenFunction &SGF, SILLocation loc,
 
   // Handle tuple destinations by destructuring them if present.
   CanType destType = dest->getType()->getCanonicalType();
-  assert(!destType->isMaterializable() || destType->isVoid());
 
   // But avoid this in the common case.
   if (!isa<TupleType>(destType)) {

test/SILGen/assignment.swift

@@ -49,3 +49,12 @@ func copyRightToLeft(p: inout P) {
   // CHECK:   end_access [[WRITE]] : $*P
   p.left = p.right
 }
+
+// SR-5919
+func stupidGames() -> ((), ()) {
+  return ((), ())
+}
+
+func assignToNestedVoid() {
+  let _: ((), ()) = stupidGames()
+}

test/SILGen/default_arguments.swift

@@ -367,3 +367,19 @@ func callThem() throws {
    defaultEscaping()
    autoclosureDefaultEscaping()
 }
+
+func tupleDefaultArg(x: (Int, Int) = (1, 2)) {}
+
+// CHECK-LABEL: sil hidden @$s17default_arguments19callTupleDefaultArgyyF : $@convention(thin) () -> ()
+// CHECK: function_ref @$s17default_arguments15tupleDefaultArg1xySi_Sit_tFfA_ : $@convention(thin) () -> (Int, Int)
+// CHECK: function_ref @$s17default_arguments15tupleDefaultArg1xySi_Sit_tF : $@convention(thin) (Int, Int) -> ()
+// CHECK: return
+func callTupleDefaultArg() {
+  tupleDefaultArg()
+}
+
+// FIXME: Should this be banned?
+func stupidGames(x: Int = 3) -> Int {
+  return x
+}
+stupidGames(x:)()