[clang-tidy] enable bugprone-unhandled-self-assignment check (#56640)

.clang-tidy

@@ -40,7 +40,7 @@ bugprone-integer-division,
 -bugprone-too-small-loop-variable,
 -bugprone-undefined-memory-manipulation,
 -bugprone-undelegated-constructor,
--bugprone-unhandled-self-assignment,
+bugprone-unhandled-self-assignment,
 bugprone-unused-raii,
 -bugprone-unused-return-value,
 -bugprone-use-after-move,

paddle/fluid/distributed/fleet_executor/dist_model_tensor_wrapper.cc

@@ -56,6 +56,9 @@ void DistModelDataBuf::Resize(size_t length) {
 }
 
 DistModelDataBuf& DistModelDataBuf::operator=(const DistModelDataBuf& other) {
+  if (this == &other) {
+    return *this;
+  }
   if (!other.memory_owned_) {
     data_ = other.data_;
     length_ = other.length_;

paddle/fluid/framework/op_desc.cc

@@ -513,6 +513,9 @@ OpDesc::OpDesc(const proto::OpDesc &desc, BlockDesc *block)
 // Explicitly implement the assign operator, Since the added
 // unique_ptr data member does not have the implicit assign operator.
 OpDesc &OpDesc::operator=(const OpDesc &other) {
+  if (this == &other) {
+    return *this;
+  }
   CopyFrom(other);
   block_ = other.block_;
   need_update_ = true;

paddle/fluid/inference/api/api.cc

@@ -52,6 +52,7 @@ PaddleBuf::PaddleBuf(PaddleBuf &&other)
 PaddleBuf::PaddleBuf(const PaddleBuf &other) { *this = other; }
 
 PaddleBuf &PaddleBuf::operator=(const PaddleBuf &other) {
+  if (this == &other) return *this;
   if (!other.memory_owned_) {
     data_ = other.data_;
     length_ = other.length_;

paddle/fluid/inference/api/paddle_infer_contrib.cc

@@ -259,6 +259,9 @@ Status::Status(const Status& status) : impl_(std::make_shared<Impl>()) {
 }
 
 Status& Status::operator=(const Status& status) noexcept {
+  if (this == &status) {
+    return *this;
+  }
   *impl_ = *status.impl_;
   return *this;
 }

paddle/phi/core/dense_tensor.cc

@@ -65,6 +65,9 @@ DenseTensor::DenseTensor(const DenseTensor& other) {
 }
 
 DenseTensor& DenseTensor::operator=(const DenseTensor& other) {
+  if (this == &other) {
+    return *this;
+  }
   meta_ = other.meta();
   holder_ = other.holder_;
   storage_properties_ =

paddle/phi/core/string_tensor.cc

@@ -43,6 +43,7 @@ StringTensor::StringTensor(const StringTensor& other) {
 }
 
 StringTensor& StringTensor::operator=(const StringTensor& other) {
+  if (this == &other) return *this;
   meta_ = other.meta();
   holder_ = other.holder_;
   return *this;