Merge pull request swiftlang#41466 from zoecarver/support-basic-inout-case

Author: zoecarver

lib/Sema/CSApply.cpp

@@ -220,14 +220,22 @@ synthesizeDependentTypeThunkParamForwarding(AbstractFunctionDecl *afd, void *con
       continue;
     }
 
-    auto paramRefExpr = new (ctx) DeclRefExpr(param, DeclNameLoc(),
-                                              /*Implicit=*/true);
+    Expr *paramRefExpr = new (ctx) DeclRefExpr(param, DeclNameLoc(),
+                                               /*Implicit=*/true);
     paramRefExpr->setType(param->getType());
 
+    if (param->isInOut()) {
+      paramRefExpr->setType(LValueType::get(param->getType()));
+
+      paramRefExpr = new (ctx) InOutExpr(
+          SourceLoc(), paramRefExpr, param->getType(), /*isImplicit*/ true);
+      paramRefExpr->setType(InOutType::get(param->getType()));
+    }
+
     auto specParamTy = specializedFuncDecl->getParameters()->get(paramIndex)->getType();
 
     Expr *argExpr = nullptr;
-    if (specParamTy->isEqual(paramRefExpr->getType())) {
+    if (specParamTy->isEqual(param->getType())) {
       argExpr = paramRefExpr;
     } else {
       argExpr = ForcedCheckedCastExpr::createImplicit(ctx, paramRefExpr,
@@ -353,9 +361,18 @@ synthesizeForwardingThunkBody(AbstractFunctionDecl *afd, void *context) {
     if (isa<MetatypeType>(param->getType().getPointer())) {
       continue;
     }
-    auto paramRefExpr = new (ctx) DeclRefExpr(param, DeclNameLoc(),
-                                             /*Implicit=*/true);
+    Expr *paramRefExpr = new (ctx) DeclRefExpr(param, DeclNameLoc(),
+                                               /*Implicit=*/true);
     paramRefExpr->setType(param->getType());
+
+    if (param->isInOut()) {
+      paramRefExpr->setType(LValueType::get(param->getType()));
+
+      paramRefExpr = new (ctx) InOutExpr(
+          SourceLoc(), paramRefExpr, param->getType(), /*isImplicit*/ true);
+      paramRefExpr->setType(InOutType::get(param->getType()));
+    }
+
     forwardingParams.push_back(Argument(SourceLoc(), Identifier(), paramRefExpr));
   }
 

test/Interop/Cxx/templates/Inputs/template-type-parameter-not-in-signature.h

@@ -33,6 +33,9 @@ T templateTypeParamUsedInReturnType(int x) { return x; }
 template <typename T>
 T templateTypeParamUsedInReferenceParam(T &t) { return t; }
 
+template <typename T, typename U>
+T templateTypeParamNotUsedInSignatureWithRef(T &t) { return t; }
+
 template <typename T, typename U>
 void templateTypeParamNotUsedInSignatureWithVarargs(...) {}
 

test/Interop/Cxx/templates/dependent-types.swift

@@ -38,6 +38,13 @@ DependentTypesTestSuite.test("Multiple dependent arguments (not inferred).") {
   expectEqual(m.getValue(), 42)
 }
 
+DependentTypesTestSuite.test("Takes inout argument and returns dependent type.") {
+  var x = 42
+  let m = refToDependent(&x) as! M<Int>
+  expectEqual(m.getValue(), 42)
+}
+
+
 // We still have some problems calling methods on Windows: SR-13129 and rdar://88391102
 #if !os(Windows)
 DependentTypesTestSuite.test("Function template methods") {

test/Interop/Cxx/templates/template-type-parameter-not-in-signature.swift

@@ -39,4 +39,10 @@ TemplateNotInSignatureTestSuite.test("Member function templates (static)") {
   Struct.templateTypeParamNotUsedInSignatureStatic(T: Int.self)
 }
 
+TemplateNotInSignatureTestSuite.test("Type not used in signature and takes an inout parameter.") {
+  var x = 42
+  let out = templateTypeParamNotUsedInSignatureWithRef(&x, U: Int.self)
+  expectEqual(out, 42)
+}
+
 runAllTests()