build: GCC9 compilation

modules/optflow/include/opencv2/optflow/sparse_matching_gpc.hpp

@@ -135,13 +135,6 @@ struct GPCTrainingParams
     CV_Assert( check() );
   }
 
-  GPCTrainingParams( const GPCTrainingParams &params )
-      : maxTreeDepth( params.maxTreeDepth ), minNumberOfSamples( params.minNumberOfSamples ), descriptorType( params.descriptorType ),
-        printProgress( params.printProgress )
-  {
-    CV_Assert( check() );
-  }
-
   bool check() const { return maxTreeDepth > 1 && minNumberOfSamples > 1; }
 };
 

modules/sfm/src/libmv_light/CMakeLists.txt

@@ -7,5 +7,8 @@ ocv_warnings_disable(CMAKE_CXX_FLAGS -Winconsistent-missing-override -Wsuggest-o
 if(CV_GCC AND CMAKE_CXX_COMPILER_VERSION VERSION_GREATER 8.0)
   ocv_warnings_disable(CMAKE_CXX_FLAGS -Wclass-memaccess)
 endif()
+if(CV_GCC AND CMAKE_CXX_COMPILER_VERSION VERSION_GREATER 9.0)
+  ocv_warnings_disable(CMAKE_CXX_FLAGS -Wdeprecated-copy)
+endif()
 
 add_subdirectory(libmv)

modules/surface_matching/src/ppf_match_3d.cpp

@@ -82,10 +82,10 @@ static KeyType hashPPF(const Vec4d& f, const double AngleStep, const double Dist
       (int)(f[1] / AngleStep),
       (int)(f[2] / AngleStep),
       (int)(f[3] / DistanceStep));
-  KeyType hashKey = 0;
+  KeyType hashKey[2] = {0, 0};  // hashMurmurx64() fills two values
 
-  murmurHash(key.val, 4*sizeof(int), 42, &hashKey);
-  return hashKey;
+  murmurHash(key.val, 4*sizeof(int), 42, &hashKey[0]);
+  return hashKey[0];
 }
 
 /*static size_t hashMurmur(uint key)