Enable -Werror in lib/ and LTC. (#2841)

Required some massaging of LTC to make it warning clean, and I had to
manually disable some warnings on the generated source files (which we
don't control).

The project is warning clean now.

The `-Werror` flag is disabled by default as we can't control everywhere
people will try to build/install. The CI enables it via
-DTORCH_MLIR_ENABLE_WERROR_FLAG=ON.

CMakeLists.txt

@@ -31,6 +31,7 @@ include(CMakeDependentOption)
 # Project options
 #-------------------------------------------------------------------------------
 
+option(TORCH_MLIR_ENABLE_WERROR_FLAG "Enable `-Werror` flag on supported directories, treat error as warning" OFF)
 option(TORCH_MLIR_USE_INSTALLED_PYTORCH "If depending on PyTorch use it as installed in the current Python environment" ON)
 
 option(TORCH_MLIR_ENABLE_REFBACKEND "Enable reference backend" ON)
@@ -53,6 +54,14 @@ cmake_dependent_option(TORCH_MLIR_ENABLE_LTC "Enables LTC backend" OFF TORCH_MLI
 
 option(TORCH_MLIR_ENABLE_ONNX_C_IMPORTER "Enables the ONNX C importer" OFF)
 
+macro(torch_mlir_enable_werror)
+  if(TORCH_MLIR_ENABLE_WERROR_FLAG)
+    if(NOT MSVC)
+      add_compile_options(-Werror)
+    endif()
+  endif()
+endmacro()
+
 #-------------------------------------------------------------------------------
 # Configure out-of-tree vs in-tree build
 #-------------------------------------------------------------------------------

build_tools/ci/build_posix.sh

@@ -42,6 +42,7 @@ cmake -S "$repo_root/externals/llvm-project/llvm" -B "$build_dir" \
   -DCMAKE_BUILD_TYPE=Release \
   -DPython3_EXECUTABLE="$(which python)" \
   -DLLVM_ENABLE_ASSERTIONS=ON \
+  -DTORCH_MLIR_ENABLE_WERROR_FLAG=ON \
   -DCMAKE_INSTALL_PREFIX="$install_dir" \
   -DCMAKE_INSTALL_LIBDIR=lib \
   -DLLVM_ENABLE_PROJECTS=mlir \

include/torch-mlir-c/Registration.h

@@ -23,7 +23,7 @@ extern "C" {
 MLIR_CAPI_EXPORTED void torchMlirRegisterAllDialects(MlirContext context);
 
 /** Registers all passes for symbolic access with the global registry. */
-MLIR_CAPI_EXPORTED void torchMlirRegisterAllPasses();
+MLIR_CAPI_EXPORTED void torchMlirRegisterAllPasses(void);
 
 #ifdef __cplusplus
 }

include/torch-mlir-c/TorchTypes.h

@@ -35,7 +35,7 @@ MLIR_CAPI_EXPORTED MlirType
 torchMlirTorchNnModuleTypeGet(MlirContext context, MlirStringRef className);
 
 /// Gets the !torch.nn.Module typeid.
-MLIR_CAPI_EXPORTED MlirTypeID torchMlirTorchNnModuleTypeGetTypeID();
+MLIR_CAPI_EXPORTED MlirTypeID torchMlirTorchNnModuleTypeGetTypeID(void);
 
 //===----------------------------------------------------------------------===//
 // torch.optional type.
@@ -53,7 +53,7 @@ MLIR_CAPI_EXPORTED MlirType
 torchMlirTorchOptionalTypeGetContained(MlirType containedType);
 
 /// Gets the !torch.optional typeid.
-MLIR_CAPI_EXPORTED MlirTypeID torchMlirTorchOptionalTypeGetTypeID();
+MLIR_CAPI_EXPORTED MlirTypeID torchMlirTorchOptionalTypeGetTypeID(void);
 
 //===----------------------------------------------------------------------===//
 // torch.tuple<T1, T2, T3> type.
@@ -75,7 +75,7 @@ MLIR_CAPI_EXPORTED MlirType torchMlirTorchTupleTypeGetType(MlirType t,
                                                            intptr_t pos);
 
 /// Gets the !torch.tuple typeid.
-MLIR_CAPI_EXPORTED MlirTypeID torchMlirTorchTupleTypeGetTypeID();
+MLIR_CAPI_EXPORTED MlirTypeID torchMlirTorchTupleTypeGetTypeID(void);
 
 //===----------------------------------------------------------------------===//
 // torch.union<T1, T2, T3> type.
@@ -97,7 +97,7 @@ MLIR_CAPI_EXPORTED MlirType torchMlirTorchUnionTypeGetType(MlirType t,
                                                            intptr_t pos);
 
 /// Gets the !torch.union typeid.
-MLIR_CAPI_EXPORTED MlirTypeID torchMlirTorchUnionTypeGetTypeID();
+MLIR_CAPI_EXPORTED MlirTypeID torchMlirTorchUnionTypeGetTypeID(void);
 
 //===----------------------------------------------------------------------===//
 // torch.list<T> type.
@@ -113,7 +113,7 @@ MLIR_CAPI_EXPORTED MlirType torchMlirTorchListTypeGet(MlirType containedType);
 MLIR_CAPI_EXPORTED MlirType torchMlirTorchListTypeGetContainedType(MlirType t);
 
 /// Gets the !torch.list typeid.
-MLIR_CAPI_EXPORTED MlirTypeID torchMlirTorchListTypeGetTypeID();
+MLIR_CAPI_EXPORTED MlirTypeID torchMlirTorchListTypeGetTypeID(void);
 
 //===----------------------------------------------------------------------===//
 // torch.Device type.
@@ -126,7 +126,7 @@ MLIR_CAPI_EXPORTED bool torchMlirTypeIsATorchDevice(MlirType t);
 MLIR_CAPI_EXPORTED MlirType torchMlirTorchDeviceTypeGet(MlirContext context);
 
 /// Gets the !torch.device typeid.
-MLIR_CAPI_EXPORTED MlirTypeID torchMlirTorchDeviceTypeGetTypeID();
+MLIR_CAPI_EXPORTED MlirTypeID torchMlirTorchDeviceTypeGetTypeID(void);
 
 //===----------------------------------------------------------------------===//
 // torch.Generator type.
@@ -139,7 +139,7 @@ MLIR_CAPI_EXPORTED bool torchMlirTypeIsATorchGenerator(MlirType t);
 MLIR_CAPI_EXPORTED MlirType torchMlirTorchGeneratorTypeGet(MlirContext context);
 
 /// Gets the !torch.generator typeid.
-MLIR_CAPI_EXPORTED MlirTypeID torchMlirTorchGeneratorTypeGetTypeID();
+MLIR_CAPI_EXPORTED MlirTypeID torchMlirTorchGeneratorTypeGetTypeID(void);
 
 //===----------------------------------------------------------------------===//
 // torch.bool type.
@@ -152,7 +152,7 @@ MLIR_CAPI_EXPORTED bool torchMlirTypeIsATorchBool(MlirType t);
 MLIR_CAPI_EXPORTED MlirType torchMlirTorchBoolTypeGet(MlirContext context);
 
 /// Gets the !torch.bool typeid.
-MLIR_CAPI_EXPORTED MlirTypeID torchMlirTorchBoolTypeGetTypeID();
+MLIR_CAPI_EXPORTED MlirTypeID torchMlirTorchBoolTypeGetTypeID(void);
 
 //===----------------------------------------------------------------------===//
 // torch.int type.
@@ -165,7 +165,7 @@ MLIR_CAPI_EXPORTED bool torchMlirTypeIsATorchInt(MlirType t);
 MLIR_CAPI_EXPORTED MlirType torchMlirTorchIntTypeGet(MlirContext context);
 
 /// Gets the !torch.int typeid.
-MLIR_CAPI_EXPORTED MlirTypeID torchMlirTorchIntTypeGetTypeID();
+MLIR_CAPI_EXPORTED MlirTypeID torchMlirTorchIntTypeGetTypeID(void);
 
 //===----------------------------------------------------------------------===//
 // torch.float type.
@@ -178,7 +178,7 @@ MLIR_CAPI_EXPORTED bool torchMlirTypeIsATorchFloat(MlirType t);
 MLIR_CAPI_EXPORTED MlirType torchMlirTorchFloatTypeGet(MlirContext context);
 
 /// Gets the !torch.float typeid.
-MLIR_CAPI_EXPORTED MlirTypeID torchMlirTorchFloatTypeGetTypeID();
+MLIR_CAPI_EXPORTED MlirTypeID torchMlirTorchFloatTypeGetTypeID(void);
 
 //===----------------------------------------------------------------------===//
 // torch.LinearParams type.
@@ -192,7 +192,7 @@ MLIR_CAPI_EXPORTED MlirType
 torchMlirTorchLinearParamsTypeGet(MlirContext context);
 
 /// Gets the !torch.linearparams typeid.
-MLIR_CAPI_EXPORTED MlirTypeID torchMlirTorchLinearParamsTypeGetTypeID();
+MLIR_CAPI_EXPORTED MlirTypeID torchMlirTorchLinearParamsTypeGetTypeID(void);
 
 //===----------------------------------------------------------------------===//
 // torch.qint8 type.
@@ -205,7 +205,7 @@ MLIR_CAPI_EXPORTED bool torchMlirTypeIsATorchQInt8(MlirType t);
 MLIR_CAPI_EXPORTED MlirType torchMlirTorchQInt8TypeGet(MlirContext context);
 
 /// Gets the !torch.qint8 typeid.
-MLIR_CAPI_EXPORTED MlirTypeID torchMlirTorchQInt8TypeGetTypeID();
+MLIR_CAPI_EXPORTED MlirTypeID torchMlirTorchQInt8TypeGetTypeID(void);
 
 //===----------------------------------------------------------------------===//
 // torch.quint8 type.
@@ -218,7 +218,7 @@ MLIR_CAPI_EXPORTED bool torchMlirTypeIsATorchQUInt8(MlirType t);
 MLIR_CAPI_EXPORTED MlirType torchMlirTorchQUInt8TypeGet(MlirContext context);
 
 /// Gets the !torch.quint8 typeid.
-MLIR_CAPI_EXPORTED MlirTypeID torchMlirTorchQUInt8TypeGetTypeID();
+MLIR_CAPI_EXPORTED MlirTypeID torchMlirTorchQUInt8TypeGetTypeID(void);
 
 //===----------------------------------------------------------------------===//
 // torch.tensor type.
@@ -266,7 +266,7 @@ MLIR_CAPI_EXPORTED MlirType
 torchMlirTorchNonValueTensorTypeGetDtype(MlirType t);
 
 /// Gets the !torch.tensor typeid.
-MLIR_CAPI_EXPORTED MlirTypeID torchMlirTorchNonValueTensorTypeGetTypeID();
+MLIR_CAPI_EXPORTED MlirTypeID torchMlirTorchNonValueTensorTypeGetTypeID(void);
 
 //===----------------------------------------------------------------------===//
 // torch.vtensor type.
@@ -312,7 +312,7 @@ torchMlirTorchValueTensorTypeGetSizes(MlirType t, int64_t *sizes);
 MLIR_CAPI_EXPORTED MlirType torchMlirTorchValueTensorTypeGetDtype(MlirType t);
 
 /// Gets the !torch.vtensor typeid.
-MLIR_CAPI_EXPORTED MlirTypeID torchMlirTorchValueTensorTypeGetTypeID();
+MLIR_CAPI_EXPORTED MlirTypeID torchMlirTorchValueTensorTypeGetTypeID(void);
 
 //===----------------------------------------------------------------------===//
 // !torch.none type.
@@ -325,7 +325,7 @@ MLIR_CAPI_EXPORTED bool torchMlirTypeIsATorchNone(MlirType t);
 MLIR_CAPI_EXPORTED MlirType torchMlirTorchNoneTypeGet(MlirContext context);
 
 /// Gets the !torch.none typeid.
-MLIR_CAPI_EXPORTED MlirTypeID torchMlirTorchNoneTypeGetTypeID();
+MLIR_CAPI_EXPORTED MlirTypeID torchMlirTorchNoneTypeGetTypeID(void);
 
 //===----------------------------------------------------------------------===//
 // !torch.str type.
@@ -338,7 +338,7 @@ MLIR_CAPI_EXPORTED bool torchMlirTypeIsATorchString(MlirType t);
 MLIR_CAPI_EXPORTED MlirType torchMlirTorchStringTypeGet(MlirContext context);
 
 /// Gets the !torch.str typeid.
-MLIR_CAPI_EXPORTED MlirTypeID torchMlirTorchStringTypeGetTypeID();
+MLIR_CAPI_EXPORTED MlirTypeID torchMlirTorchStringTypeGetTypeID(void);
 
 //===----------------------------------------------------------------------===//
 // !torch.any type.
@@ -351,7 +351,7 @@ MLIR_CAPI_EXPORTED bool torchMlirTypeIsATorchAny(MlirType t);
 MLIR_CAPI_EXPORTED MlirType torchMlirTorchAnyTypeGet(MlirContext context);
 
 /// Gets the !torch.any typeid.
-MLIR_CAPI_EXPORTED MlirTypeID torchMlirTorchAnyTypeGetTypeID();
+MLIR_CAPI_EXPORTED MlirTypeID torchMlirTorchAnyTypeGetTypeID(void);
 
 //===----------------------------------------------------------------------===//
 // !torch.number type.
@@ -364,7 +364,7 @@ MLIR_CAPI_EXPORTED bool torchMlirTypeIsATorchNumber(MlirType t);
 MLIR_CAPI_EXPORTED MlirType torchMlirTorchNumberTypeGet(MlirContext context);
 
 /// Gets the !torch.number typeid.
-MLIR_CAPI_EXPORTED MlirTypeID torchMlirTorchNumberTypeGetTypeID();
+MLIR_CAPI_EXPORTED MlirTypeID torchMlirTorchNumberTypeGetTypeID(void);
 
 //===----------------------------------------------------------------------===//
 // !torch.dict type.
@@ -387,7 +387,7 @@ MLIR_CAPI_EXPORTED MlirType torchMlirTorchDictTypeGetKeyType(MlirType t);
 MLIR_CAPI_EXPORTED MlirType torchMlirTorchDictTypeGetValueType(MlirType t);
 
 /// Gets the !torch.dict typeid.
-MLIR_CAPI_EXPORTED MlirTypeID torchMlirTorchDictTypeGetTypeID();
+MLIR_CAPI_EXPORTED MlirTypeID torchMlirTorchDictTypeGetTypeID(void);
 
 #ifdef __cplusplus
 }

lib/CMakeLists.txt

@@ -1,3 +1,5 @@
+torch_mlir_enable_werror()
+
 add_subdirectory(CAPI)
 add_subdirectory(Conversion)
 add_subdirectory(Dialect)

lib/Conversion/TorchOnnxToTorch/DefaultDomainQtoZ.cpp

@@ -673,7 +673,7 @@ void mlir::torch::onnx_c::populateDefaultDomainQtoZ(
         if (operands.size() == 1) {
           if (noop_with_empty_axes == 0) {
             MLIRContext *context = binder.op->getContext();
-            auto rank =
+            int rank =
                 data.getType().cast<Torch::ValueTensorType>().getSizes().size();
             SmallVector<Value, 1> dims;
             for (int i = 0; i < rank; i++) {

projects/ltc/csrc/base_lazy_backend/CMakeLists.txt

@@ -2,11 +2,21 @@
 # Setup PyTorch/LTC
 #-------------------------------------------------------------------------------
 
+torch_mlir_enable_werror()
+
 set(LTC_GENERATED
   generated/LazyNativeFunctions.cpp
   generated/RegisterLazy.cpp
   generated/shape_inference.cpp
 )
+
+# The auto generated files trigger some warnings we can't do anything about.
+if(NOT MSVC)
+  set_source_files_properties(${LTC_GENERATED}
+    PROPERTIES COMPILE_FLAGS "-Wno-sign-compare -Wno-unused-function"
+  )
+endif()
+
 set(LTC_BACKEND_DEPENDS
   mlir_lowering_context.cpp
   mlir_native_functions.cpp

projects/ltc/csrc/base_lazy_backend/dynamic_ir.cpp

@@ -24,7 +24,7 @@ std::string DimensionNode::ToString() const { return "DimensionNode"; }
 SizeNode::SizeNode(Value input, size_t dim)
     : DimensionNode(OpKind{c10::Symbol::fromQualString("aten::size")}, {input},
                     MHash(dim)),
-      dim_(dim){};
+      dim_(dim) {}
 
 int64_t SizeNode::getStaticValue() const {
   return dynamic_cast<const TorchMlirNode *>(operand(0).node)
@@ -35,7 +35,7 @@ int64_t SizeNode::getStaticValue() const {
 std::string SizeNode::ToString() const { return "SizeNode"; }
 
 SizeAdd::SizeAdd(Value a, Value b)
-    : DimensionNode(OpKind{c10::Symbol::fromQualString("aten::add")}, {a, b}){};
+    : DimensionNode(OpKind{c10::Symbol::fromQualString("aten::add")}, {a, b}) {}
 
 int64_t SizeAdd::getStaticValue() const {
   return dynamic_cast<const DimensionNode *>(operand(0).node)
@@ -46,7 +46,7 @@ int64_t SizeAdd::getStaticValue() const {
 std::string SizeAdd::ToString() const { return "SizeAdd"; }
 
 SizeMul::SizeMul(Value a, Value b)
-    : DimensionNode(OpKind{c10::Symbol::fromQualString("aten::mul")}, {a, b}){};
+    : DimensionNode(OpKind{c10::Symbol::fromQualString("aten::mul")}, {a, b}) {}
 
 int64_t SizeMul::getStaticValue() const {
   return dynamic_cast<const DimensionNode *>(operand(0).node)
@@ -57,7 +57,7 @@ int64_t SizeMul::getStaticValue() const {
 std::string SizeMul::ToString() const { return "SizeMul"; }
 
 SizeDiv::SizeDiv(Value a, Value b)
-    : DimensionNode(OpKind{c10::Symbol::fromQualString("aten::div")}, {a, b}){};
+    : DimensionNode(OpKind{c10::Symbol::fromQualString("aten::div")}, {a, b}) {}
 
 int64_t SizeDiv::getStaticValue() const {
   TORCH_CHECK(

projects/ltc/csrc/base_lazy_backend/mlir_lowering_context.h

@@ -150,15 +150,14 @@ public:
 
 protected:
   size_t num_parameters_;
-  std::unordered_map<int, std::string> parameters_map_;
-  std::vector<std::string> parameter_names_;
-  std::vector<Shape> parameter_shapes_;
-  Shape result_shape_;
-
   MlirModule module_op_;
   MlirContext mlir_context_;
   std::shared_ptr<torch::jit::Graph> graph_;
   InputOutputAliases input_output_aliases_;
+  std::unordered_map<int, std::string> parameters_map_;
+  std::vector<std::string> parameter_names_;
+  std::vector<Shape> parameter_shapes_;
+  Shape result_shape_;
 };
 
 } // namespace lazy

projects/ltc/csrc/base_lazy_backend/mlir_native_functions.cpp

@@ -67,7 +67,7 @@ c10::optional<at::Tensor> to_meta(const c10::optional<at::Tensor> &tensor) {
   return c10::nullopt;
 }
 
-std::vector<at::Tensor> to_meta(at::ITensorListRef t_list) {
+[[maybe_unused]] std::vector<at::Tensor> to_meta(at::ITensorListRef t_list) {
   std::vector<at::Tensor> outs;
   outs.reserve(t_list.size());
   for (const auto &tensor : t_list) {
@@ -92,7 +92,7 @@ namespace lazy {
 
 namespace {
 
-at::Tensor
+[[maybe_unused]] at::Tensor
 CreateLtcTensor(const at::Tensor &tensor,
                 const c10::optional<torch::lazy::BackendDevice> &device) {
   if (tensor.defined() && device) {
@@ -102,7 +102,7 @@ CreateLtcTensor(const at::Tensor &tensor,
   return tensor;
 }
 
-c10::optional<torch::lazy::BackendDevice>
+[[maybe_unused]] c10::optional<torch::lazy::BackendDevice>
 GetLtcDevice(const c10::optional<c10::Device> &device) {
   if (!device) {
     return c10::nullopt;
@@ -334,7 +334,7 @@ at::Tensor LazyNativeFunctions::_to_copy(
             std::move(node), lazy_self->GetDevice()));
     return result;
   }
-};
+}
 
 at::Tensor LazyNativeFunctions::_unsafe_view(const at::Tensor &self,
                                              at::IntArrayRef size) {

projects/ltc/csrc/base_lazy_backend/utils/sys_utils.h

@@ -14,8 +14,8 @@ static T GetEnv(const std::string &name, const T &default_value = T(0)) {
   return T(std::atoi(env));
 }
 
-static std::string GetEnvString(const std::string &name,
-                                const std::string &default_value) {
+[[maybe_unused]] static std::string
+GetEnvString(const std::string &name, const std::string &default_value) {
   const char *env = std::getenv(name.c_str());
   if (!env) {
     return default_value;
@@ -23,7 +23,7 @@ static std::string GetEnvString(const std::string &name,
   return std::string(env);
 }
 
-static bool GetEnvBool(const char *name, bool defval) {
+[[maybe_unused]] static bool GetEnvBool(const char *name, bool defval) {
   const char *env = std::getenv(name);
   if (env == nullptr) {
     return defval;