Add explicit Rule of Five defaults for classes with user-provided destructors (#5094)

Summary:
Pull Request resolved: #5094

Fix 73 `cppcoreguidelines-special-member-functions` and `clang-diagnostic-deprecated-copy-with-user-provided-dtor` lint warnings across 32 header files by adding explicit `= default` declarations for copy/move constructors and assignment operators to 46 classes that define user-provided destructors.

In C++17+, the implicit generation of copy constructors for classes with user-provided destructors is deprecated. Adding explicit `= default` preserves the existing behavior while satisfying the Rule of Five. Default constructors were also added where needed to maintain existing default-constructibility.

Differential Revision: D100592061

Author: junjieqi

faiss/AutoTune.h

@@ -51,6 +51,11 @@ struct AutoTuneCriterion {
     virtual double evaluate(const float* D, const idx_t* I) const = 0;
 
     virtual ~AutoTuneCriterion() {}
+    // rule of five defaults
+    AutoTuneCriterion(const AutoTuneCriterion&) = default;
+    AutoTuneCriterion& operator=(const AutoTuneCriterion&) = default;
+    AutoTuneCriterion(AutoTuneCriterion&&) = default;
+    AutoTuneCriterion& operator=(AutoTuneCriterion&&) = default;
 };
 
 struct OneRecallAtRCriterion : AutoTuneCriterion {
@@ -61,6 +66,11 @@ struct OneRecallAtRCriterion : AutoTuneCriterion {
     double evaluate(const float* D, const idx_t* I) const override;
 
     ~OneRecallAtRCriterion() override {}
+    // rule of five defaults
+    OneRecallAtRCriterion(const OneRecallAtRCriterion&) = default;
+    OneRecallAtRCriterion& operator=(const OneRecallAtRCriterion&) = default;
+    OneRecallAtRCriterion(OneRecallAtRCriterion&&) = default;
+    OneRecallAtRCriterion& operator=(OneRecallAtRCriterion&&) = default;
 };
 
 struct IntersectionCriterion : AutoTuneCriterion {
@@ -71,6 +81,11 @@ struct IntersectionCriterion : AutoTuneCriterion {
     double evaluate(const float* D, const idx_t* I) const override;
 
     ~IntersectionCriterion() override {}
+    // rule of five defaults
+    IntersectionCriterion(const IntersectionCriterion&) = default;
+    IntersectionCriterion& operator=(const IntersectionCriterion&) = default;
+    IntersectionCriterion(IntersectionCriterion&&) = default;
+    IntersectionCriterion& operator=(IntersectionCriterion&&) = default;
 };
 
 /**
@@ -218,6 +233,11 @@ struct ParameterSpace {
             OperatingPoints* ops) const;
 
     virtual ~ParameterSpace() {}
+    // rule of five defaults
+    ParameterSpace(const ParameterSpace&) = default;
+    ParameterSpace& operator=(const ParameterSpace&) = default;
+    ParameterSpace(ParameterSpace&&) = default;
+    ParameterSpace& operator=(ParameterSpace&&) = default;
 };
 
 } // namespace faiss

faiss/Clustering.h

@@ -145,6 +145,11 @@ struct Clustering : ClusteringParameters {
     void post_process_centroids();
 
     virtual ~Clustering() {}
+    // rule of five defaults
+    Clustering(const Clustering&) = default;
+    Clustering& operator=(const Clustering&) = default;
+    Clustering(Clustering&&) = default;
+    Clustering& operator=(Clustering&&) = default;
 };
 
 /** Exact 1D clustering algorithm
@@ -159,6 +164,11 @@ struct Clustering1D : Clustering {
     void train_exact(idx_t n, const float* x);
 
     virtual ~Clustering1D() {}
+    // rule of five defaults
+    Clustering1D(const Clustering1D&) = default;
+    Clustering1D& operator=(const Clustering1D&) = default;
+    Clustering1D(Clustering1D&&) = default;
+    Clustering1D& operator=(Clustering1D&&) = default;
 };
 
 struct ProgressiveDimClusteringParameters : ClusteringParameters {
@@ -174,6 +184,14 @@ struct ProgressiveDimIndexFactory {
     virtual Index* operator()(int dim);
 
     virtual ~ProgressiveDimIndexFactory() {}
+    // rule of five defaults
+    ProgressiveDimIndexFactory() = default;
+    ProgressiveDimIndexFactory(const ProgressiveDimIndexFactory&) = default;
+    ProgressiveDimIndexFactory& operator=(const ProgressiveDimIndexFactory&) =
+            default;
+    ProgressiveDimIndexFactory(ProgressiveDimIndexFactory&&) = default;
+    ProgressiveDimIndexFactory& operator=(ProgressiveDimIndexFactory&&) =
+            default;
 };
 
 /** K-means clustering with progressive dimensions used
@@ -208,6 +226,12 @@ struct ProgressiveDimClustering : ProgressiveDimClusteringParameters {
     void train(idx_t n, const float* x, ProgressiveDimIndexFactory& factory);
 
     virtual ~ProgressiveDimClustering() {}
+    // rule of five defaults
+    ProgressiveDimClustering(const ProgressiveDimClustering&) = default;
+    ProgressiveDimClustering& operator=(const ProgressiveDimClustering&) =
+            default;
+    ProgressiveDimClustering(ProgressiveDimClustering&&) = default;
+    ProgressiveDimClustering& operator=(ProgressiveDimClustering&&) = default;
 };
 
 /** simplified interface

faiss/Index.h

@@ -90,6 +90,12 @@ struct SearchParameters {
     IDSelector* sel = nullptr;
     /// make sure we can dynamic_cast this
     virtual ~SearchParameters() {}
+    // rule of five defaults
+    SearchParameters() = default;
+    SearchParameters(const SearchParameters&) = default;
+    SearchParameters& operator=(const SearchParameters&) = default;
+    SearchParameters(SearchParameters&&) = default;
+    SearchParameters& operator=(SearchParameters&&) = default;
 };
 
 /** Abstract structure for an index, supports adding vectors and searching
@@ -123,6 +129,11 @@ struct Index {
               metric_arg(0) {}
 
     virtual ~Index();
+    // rule of five defaults
+    Index(const Index&) = default;
+    Index& operator=(const Index&) = default;
+    Index(Index&&) = default;
+    Index& operator=(Index&&) = default;
 
     /** Perform training on a representative set of vectors
      *

faiss/Index2Layer.h

@@ -48,6 +48,11 @@ struct Index2Layer : IndexFlatCodes {
 
     Index2Layer();
     ~Index2Layer() override;
+    // rule of five defaults
+    Index2Layer(const Index2Layer&) = default;
+    Index2Layer& operator=(const Index2Layer&) = default;
+    Index2Layer(Index2Layer&&) = default;
+    Index2Layer& operator=(Index2Layer&&) = default;
 
     void train(idx_t n, const float* x) override;
 
@@ -71,6 +76,7 @@ struct Index2Layer : IndexFlatCodes {
 };
 
 // block size used in Index2Layer::sa_encode
-FAISS_API extern int index2layer_sa_encode_bs;
+FAISS_API extern int
+        index2layer_sa_encode_bs; // NOLINT(facebook-avoid-non-const-global-variables)
 
 } // namespace faiss

faiss/IndexAdditiveQuantizer.h

@@ -191,6 +191,15 @@ struct AdditiveCoarseQuantizer : Index {
 struct SearchParametersResidualCoarseQuantizer : SearchParameters {
     float beam_factor = 4.0f;
     ~SearchParametersResidualCoarseQuantizer() {}
+    // rule of five defaults
+    SearchParametersResidualCoarseQuantizer(
+            const SearchParametersResidualCoarseQuantizer&) = default;
+    SearchParametersResidualCoarseQuantizer& operator=(
+            const SearchParametersResidualCoarseQuantizer&) = default;
+    SearchParametersResidualCoarseQuantizer(
+            SearchParametersResidualCoarseQuantizer&&) = default;
+    SearchParametersResidualCoarseQuantizer& operator=(
+            SearchParametersResidualCoarseQuantizer&&) = default;
 };
 
 /** The ResidualCoarseQuantizer is a bit specialized compared to the

faiss/IndexAdditiveQuantizerFastScan.h

@@ -50,6 +50,14 @@ struct IndexAdditiveQuantizerFastScan : IndexFastScan {
     IndexAdditiveQuantizerFastScan();
 
     ~IndexAdditiveQuantizerFastScan() override;
+    // rule of five defaults
+    IndexAdditiveQuantizerFastScan(const IndexAdditiveQuantizerFastScan&) =
+            default;
+    IndexAdditiveQuantizerFastScan& operator=(
+            const IndexAdditiveQuantizerFastScan&) = default;
+    IndexAdditiveQuantizerFastScan(IndexAdditiveQuantizerFastScan&&) = default;
+    IndexAdditiveQuantizerFastScan& operator=(
+            IndexAdditiveQuantizerFastScan&&) = default;
 
     /// build from an existing IndexAQ
     explicit IndexAdditiveQuantizerFastScan(

faiss/IndexBinary.h

@@ -45,6 +45,11 @@ struct IndexBinary {
     explicit IndexBinary(idx_t d = 0, MetricType metric = METRIC_L2);
 
     virtual ~IndexBinary();
+    // rule of five defaults
+    IndexBinary(const IndexBinary&) = default;
+    IndexBinary& operator=(const IndexBinary&) = default;
+    IndexBinary(IndexBinary&&) = default;
+    IndexBinary& operator=(IndexBinary&&) = default;
 
     /** Perform training on a representative set of vectors.
      *

faiss/IndexBinaryFromFloat.h

@@ -33,6 +33,11 @@ struct IndexBinaryFromFloat : IndexBinary {
     explicit IndexBinaryFromFloat(Index* index);
 
     ~IndexBinaryFromFloat() override;
+    // rule of five defaults
+    IndexBinaryFromFloat(const IndexBinaryFromFloat&) = default;
+    IndexBinaryFromFloat& operator=(const IndexBinaryFromFloat&) = default;
+    IndexBinaryFromFloat(IndexBinaryFromFloat&&) = default;
+    IndexBinaryFromFloat& operator=(IndexBinaryFromFloat&&) = default;
 
     void add(idx_t n, const uint8_t* x) override;
 

faiss/IndexBinaryHNSW.h

@@ -45,6 +45,11 @@ struct IndexBinaryHNSW : IndexBinary {
     explicit IndexBinaryHNSW(IndexBinary* storage, int M = 32);
 
     ~IndexBinaryHNSW() override;
+    // rule of five defaults
+    IndexBinaryHNSW(const IndexBinaryHNSW&) = default;
+    IndexBinaryHNSW& operator=(const IndexBinaryHNSW&) = default;
+    IndexBinaryHNSW(IndexBinaryHNSW&&) = default;
+    IndexBinaryHNSW& operator=(IndexBinaryHNSW&&) = default;
 
     DistanceComputer* get_distance_computer() const;
 

faiss/IndexBinaryHash.h

@@ -77,7 +77,8 @@ struct IndexBinaryHashStats {
     void reset();
 };
 
-FAISS_API extern IndexBinaryHashStats indexBinaryHash_stats;
+FAISS_API extern IndexBinaryHashStats
+        indexBinaryHash_stats; // NOLINT(facebook-avoid-non-const-global-variables)
 
 /** just uses the b first bits as a hash value */
 struct IndexBinaryMultiHash : IndexBinary {
@@ -100,6 +101,11 @@ struct IndexBinaryMultiHash : IndexBinary {
     IndexBinaryMultiHash();
 
     ~IndexBinaryMultiHash() override;
+    // rule of five defaults
+    IndexBinaryMultiHash(const IndexBinaryMultiHash&) = default;
+    IndexBinaryMultiHash& operator=(const IndexBinaryMultiHash&) = default;
+    IndexBinaryMultiHash(IndexBinaryMultiHash&&) = default;
+    IndexBinaryMultiHash& operator=(IndexBinaryMultiHash&&) = default;
 
     void reset() override;