cmake: silence GCC-9 warnings from rocksdb

GCC-9 complains:

rocksdb/db/version_edit.h:86:8: warning: implicitly-declared ‘constexpr
rocksdb::FileDescriptor::FileDescriptor(const rocksdb::FileDescriptor&)’
is deprecated [-Wdeprecated-copy]
   86 | struct FileMetaData {
      |        ^~~~~~~~~~~~
/var/ssd/ceph/src/rocksdb/db/version_edit.h:55:19: note: because
‘rocksdb::FileDescriptor’ has user-provided ‘rocksdb::FileDescriptor&
rocksdb::FileDescriptor::operator=(const rocksdb::FileDescriptor&)’
   55 |   FileDescriptor& operator=(const FileDescriptor& fd) {
      |                   ^~~~~~~~

Signed-off-by: Kefu Chai <kchai@redhat.com>

diff --git a/cmake/modules/BuildRocksDB.cmake b/cmake/modules/BuildRocksDB.cmake
index fe55765ed96133cc1508ac6fe63d5d19f9e1ba81..2ee07764348e1be66d6abd4237826203fda04c33 100644 (file)
--- a/cmake/modules/BuildRocksDB.cmake
+++ b/cmake/modules/BuildRocksDB.cmake
@@ -40,7 +40,19 @@ function(build_rocksdb)
   list(APPEND rocksdb_CMAKE_ARGS -G${CMAKE_GENERATOR})
   CHECK_C_COMPILER_FLAG("-Wno-stringop-truncation" HAS_WARNING_STRINGOP_TRUNCATION)
   if(HAS_WARNING_STRINGOP_TRUNCATION)
-    list(APPEND rocksdb_CMAKE_ARGS -DCMAKE_C_FLAGS="-Wno-stringop-truncation")
+    list(APPEND rocksdb_CMAKE_ARGS -DCMAKE_C_FLAGS=-Wno-stringop-truncation)
+  endif()
+  include(CheckCXXCompilerFlag)
+  check_cxx_compiler_flag("-Wno-deprecated-copy" HAS_WARNING_DEPRECATED_COPY)
+  if(HAS_WARNING_DEPRECATED_COPY)
+    set(rocksdb_CXX_FLAGS -Wno-deprecated-copy)
+  endif()
+  check_cxx_compiler_flag("-Wno-pessimizing-move" HAS_WARNING_PESSIMIZING_MOVE)
+  if(HAS_WARNING_PESSIMIZING_MOVE)
+    set(rocksdb_CXX_FLAGS "${rocksdb_CXX_FLAGS} -Wno-pessimizing-move")
+  endif()
+  if(rocksdb_CXX_FLAGS)
+    list(APPEND rocksdb_CMAKE_ARGS -DCMAKE_CXX_FLAGS='${rocksdb_CXX_FLAGS}')
   endif()
   # we use an external project and copy the sources to bin directory to ensure
   # that object files are built outside of the source tree.