Fix default arguments to only map to null if pointers

This bug is revealed by properly fixing the reading of ABI parameters in the parser.

Signed-off-by: Dimitar Dobrev <dpldobrev@protonmail.com>

Author: ddobrev

src/AST/FunctionExtensions.cs

@@ -16,18 +16,8 @@ public static IList<Parameter> GatherInternalParams(this Function function,
 
             var pointer = new QualifiedType(new PointerType(new QualifiedType(new BuiltinType(PrimitiveType.Void))));
 
-            if (isInstanceMethod && !isItaniumLikeAbi)
-            {
-                @params.Add(new Parameter
-                    {
-                        QualifiedType = pointer,
-                        Name = "__instance",
-                        Namespace = function
-                    });
-            }
-
-            if (!function.HasIndirectReturnTypeParameter &&
-                isInstanceMethod && isItaniumLikeAbi)
+            if (isInstanceMethod &&
+                (!isItaniumLikeAbi || !function.HasIndirectReturnTypeParameter))
             {
                 @params.Add(new Parameter
                     {

src/CppParser/Parser.cpp

@@ -2923,14 +2923,9 @@ Enumeration::Item* Parser::WalkEnumItem(clang::EnumConstantDecl* ECD)
 static const clang::CodeGen::CGFunctionInfo& GetCodeGenFunctionInfo(
     clang::CodeGen::CodeGenTypes* CodeGenTypes, const clang::FunctionDecl* FD)
 {
-    using namespace clang;
-    if (auto CD = dyn_cast<clang::CXXConstructorDecl>(FD)) {
-        return CodeGenTypes->arrangeCXXStructorDeclaration(CD);
-    } else if (auto DD = dyn_cast<clang::CXXDestructorDecl>(FD)) {
-        return CodeGenTypes->arrangeCXXStructorDeclaration(DD);
-    }
-
-    return CodeGenTypes->arrangeFunctionDeclaration(FD);
+    auto FTy = FD->getType()->getCanonicalTypeUnqualified();
+    return CodeGenTypes->arrangeFreeFunctionType(
+        FTy.castAs<clang::FunctionProtoType>());
 }
 
 bool Parser::CanCheckCodeGenInfo(clang::Sema& S, const clang::Type* Ty)
@@ -3294,9 +3289,8 @@ void Parser::WalkFunction(const clang::FunctionDecl* FD, Function* F,
     unsigned Index = 0;
     for (const auto& Arg : CGInfo.arguments())
     {
-        if (Index >= F->Parameters.size())
-            continue;
-        F->Parameters[Index++]->isIndirect = Arg.info.isIndirect();
+        F->Parameters[Index++]->isIndirect =
+            Arg.info.isIndirect() && !Arg.info.getIndirectByVal();
     }
 
     MarkValidity(F);

src/Generator/Driver.cs

@@ -253,11 +253,6 @@ public void SetupPasses(ILibrary library)
 
             if (Options.IsCSharpGenerator)
             {
-                if (Options.GenerateDefaultValuesForArguments)
-                {
-                    TranslationUnitPasses.AddPass(new FixDefaultParamValuesOfOverridesPass());
-                    TranslationUnitPasses.AddPass(new HandleDefaultParamValuesPass());
-                }
                 TranslationUnitPasses.AddPass(new GenerateAbstractImplementationsPass());
                 TranslationUnitPasses.AddPass(new MultipleInheritancePass());
             }

src/Generator/Generators/CSharp/CSharpGenerator.cs

@@ -25,6 +25,12 @@ public override List<CodeGenerator> Generate(IEnumerable<TranslationUnit> units)
 
         public override bool SetupPasses()
         {
+            if (Context.Options.GenerateDefaultValuesForArguments)
+            {
+                Context.TranslationUnitPasses.AddPass(new FixDefaultParamValuesOfOverridesPass());
+                Context.TranslationUnitPasses.AddPass(new HandleDefaultParamValuesPass());
+            }
+
             // Both the CheckOperatorsOverloadsPass and CheckAbiParameters can
             // create and and new parameters to functions and methods. Make sure
             // CheckAbiParameters runs last because hidden structure parameters

src/Generator/Passes/HandleDefaultParamValuesPass.cs

@@ -75,7 +75,7 @@ public override bool VisitFunctionDecl(Function function)
         {
             var desugared = type.Desugar();
 
-            if (!desugared.IsPrimitiveTypeConvertibleToRef() &&
+            if (desugared.IsAddress() && !desugared.IsPrimitiveTypeConvertibleToRef() &&
                 (expression.String == "0" || expression.String == "nullptr"))
             {
                 result = desugared.GetPointee()?.Desugar() is FunctionType ?

tests/CSharp/CSharp.Tests.cs

@@ -249,7 +249,7 @@ public void TestDefaultArguments()
             methodsWithDefaultValues.DefaultMappedToZeroEnum();
             methodsWithDefaultValues.DefaultMappedToEnumAssignedWithCtor();
             methodsWithDefaultValues.DefaultZeroMappedToEnumAssignedWithCtor();
-            methodsWithDefaultValues.DefaultImplicitCtorInt();
+            Assert.That(methodsWithDefaultValues.DefaultImplicitCtorInt().Priv, Is.EqualTo(0));
             methodsWithDefaultValues.DefaultImplicitCtorChar();
             methodsWithDefaultValues.DefaultImplicitCtorFoo();
             methodsWithDefaultValues.DefaultImplicitCtorEnum();

tests/CSharp/CSharp.cpp

@@ -117,7 +117,7 @@ Quux::Quux() : _setterWithDefaultOverload(0)
 
 Quux::Quux(int i) : Quux()
 {
-
+    priv = i;
 }
 
 Quux::Quux(char c) : Quux()
@@ -139,6 +139,11 @@ Quux::~Quux()
     }
 }
 
+int Quux::getPriv() const
+{
+    return priv;
+}
+
 Foo* Quux::setterWithDefaultOverload()
 {
     return _setterWithDefaultOverload;
@@ -645,8 +650,9 @@ void MethodsWithDefaultValues::defaultZeroMappedToEnumAssignedWithCtor(DefaultZe
 {
 }
 
-void MethodsWithDefaultValues::defaultImplicitCtorInt(Quux arg)
+Quux MethodsWithDefaultValues::defaultImplicitCtorInt(Quux arg)
 {
+    return arg;
 }
 
 void MethodsWithDefaultValues::defaultImplicitCtorChar(Quux arg)

tests/CSharp/CSharp.h

@@ -56,6 +56,7 @@ class DLL_API Quux
     Quux(Foo f);
     ~Quux();
 
+    int getPriv() const;
     Foo* setterWithDefaultOverload();
     void setSetterWithDefaultOverload(Foo* value = new Foo());
 
@@ -419,7 +420,7 @@ class DLL_API MethodsWithDefaultValues : public Quux
     void defaultMappedToZeroEnum(QFlags<Flags> qFlags = 0);
     void defaultMappedToEnumAssignedWithCtor(QFlags<Flags> qFlags = QFlags<Flags>());
     void defaultZeroMappedToEnumAssignedWithCtor(DefaultZeroMappedToEnum defaultZeroMappedToEnum = DefaultZeroMappedToEnum());
-    void defaultImplicitCtorInt(Quux arg = 0);
+    Quux defaultImplicitCtorInt(Quux arg = 0);
     void defaultImplicitCtorChar(Quux arg = 'a');
     void defaultImplicitCtorFoo(Quux arg = Foo());
     // this looks the same test as 'defaultRefTypeEnumImplicitCtor' two lines below