Found the following significant warnings:
  ./third_party/protobuf-lite/google/protobuf/arena.h:306:24: warning: ‘template<class _Tp> struct std::is_pod’ is deprecated: use 'is_standard_layout && is_trivial' instead [-Wdeprecated-declarations]
  ./third_party/protobuf-lite/google/protobuf/repeated_field.h:441:34: warning: ‘template<class _Tp> struct std::is_pod’ is deprecated: use 'is_standard_layout && is_trivial' instead [-Wdeprecated-declarations]
  ./third_party/protobuf-lite/google/protobuf/repeated_field.h:504:20: warning: ‘template<class _Tp> struct std::is_pod’ is deprecated: use 'is_standard_layout && is_trivial' instead [-Wdeprecated-declarations]
  ./third_party/protobuf-lite/google/protobuf/generated_message_table_driven.h:206:20: warning: ‘template<class _Tp> struct std::is_pod’ is deprecated: use 'is_standard_layout && is_trivial' instead [-Wdeprecated-declarations]
  ./third_party/protobuf-lite/google/protobuf/generated_message_table_driven.h:207:20: warning: ‘template<class _Tp> struct std::is_pod’ is deprecated: use 'is_standard_layout && is_trivial' instead [-Wdeprecated-declarations]
  ./third_party/protobuf-lite/google/protobuf/generated_message_table_driven.h:208:20: warning: ‘template<class _Tp> struct std::is_pod’ is deprecated: use 'is_standard_layout && is_trivial' instead [-Wdeprecated-declarations]
  ./third_party/protobuf-lite/google/protobuf/generated_message_table_driven.h:209:20: warning: ‘template<class _Tp> struct std::is_pod’ is deprecated: use 'is_standard_layout && is_trivial' instead [-Wdeprecated-declarations]
  ./third_party/protobuf-lite/google/protobuf/generated_message_table_driven.h:210:20: warning: ‘template<class _Tp> struct std::is_pod’ is deprecated: use 'is_standard_layout && is_trivial' instead [-Wdeprecated-declarations]
  ./third_party/protobuf-lite/google/protobuf/generated_message_table_driven.h:211:20: warning: ‘template<class _Tp> struct std::is_pod’ is deprecated: use 'is_standard_layout && is_trivial' instead [-Wdeprecated-declarations]
  ./third_party/protobuf-lite/google/protobuf/generated_message_table_driven_lite.h:90:22: warning: ‘template<class _Tp> struct std::is_pod’ is deprecated: use 'is_standard_layout && is_trivial' instead [-Wdeprecated-declarations]
  ./third_party/protobuf-lite/google/protobuf/generated_message_table_driven_lite.h:107:22: warning: ‘template<class _Tp> struct std::is_pod’ is deprecated: use 'is_standard_layout && is_trivial' instead [-Wdeprecated-declarations]
  ./third_party/protobuf-lite/google/protobuf/generated_message_table_driven_lite.h:129:22: warning: ‘template<class _Tp> struct std::is_pod’ is deprecated: use 'is_standard_layout && is_trivial' instead [-Wdeprecated-declarations]
See ‘/home/hornik/tmp/R.check/r-devel-gcc/Work/PKGS/sentencepiece.Rcheck/00install.out’ for details.
* used C++ compiler: ‘g++-15 (Debian 15.2.0-12) 15.2.0’