compilation error with cereal 1.3.1

[lkeegan]

Compiling with -DWITH_SYSTEM_CEREAL=ON and an external installation of cereal v1.3.1 gives this compilation error:

In file included from /home/lkeegan/SSC/symengine/symengine/tests/basic/test_serialize-cereal.cpp:4:
/home/lkeegan/SSC/symengine/symengine/serialize-cereal.h:288:44: error: reference to type 'const std::shared_ptr<const void>' could not bind to an rvalue of type 'const SymEngine::Basic *'
    uint32_t id = ar.registerSharedPointer(ptr.get());
                                           ^~~~~~~~~
/home/lkeegan/SSC/symengine/symengine/serialize-cereal.h:311:5: note: in instantiation of function template specialization 'SymEngine::save_basic<cereal::BinaryOutputArchive>' requested here
    save_basic(ar, rcp_static_cast<const Basic>(ptr));
    ^
/home/lkeegan/install/include/cereal/cereal.hpp:532:9: note: in instantiation of function template specialization 'SymEngine::save<cereal::BinaryOutputArchive, SymEngine::Basic>' requested here
        CEREAL_SAVE_FUNCTION_NAME(*self, t);
        ^
/home/lkeegan/install/include/cereal/macros.hpp:92:35: note: expanded from macro 'CEREAL_SAVE_FUNCTION_NAME'
#define CEREAL_SAVE_FUNCTION_NAME save
                                  ^
/home/lkeegan/install/include/cereal/cereal.hpp:444:15: note: in instantiation of function template specialization 'cereal::OutputArchive<cereal::BinaryOutputArchive, 1>::processImpl<SymEngine::RCP<const SymEngine::Basic>, (cereal::traits::detail::sfinae)0>' requested here
        self->processImpl( head );
              ^
/home/lkeegan/install/include/cereal/cereal.hpp:333:15: note: in instantiation of function template specialization 'cereal::OutputArchive<cereal::BinaryOutputArchive, 1>::process<SymEngine::RCP<const SymEngine::Basic> &>' requested here
        self->process( std::forward<Types>( args )... );
              ^
/home/lkeegan/SSC/symengine/symengine/tests/basic/test_serialize-cereal.cpp:22:5: note: in instantiation of function template specialization 'cereal::OutputArchive<cereal::BinaryOutputArchive, 1>::operator()<SymEngine::RCP<const SymEngine::Basic> &>' requested here
    cereal::BinaryOutputArchive{oss}(obj);
    ^
/home/lkeegan/SSC/symengine/symengine/tests/basic/test_serialize-cereal.cpp:37:44: note: in instantiation of function template specialization 'dumps<SymEngine::Basic>' requested here
    RCP<const Basic> basic2 = loads<Basic>(dumps<Basic>(basic1));
                                           ^
/home/lkeegan/install/include/cereal/cereal.hpp:398:85: note: passing argument to parameter 'sharedPointer' here
      inline std::uint32_t registerSharedPointer(const std::shared_ptr<const void>& sharedPointer)
                                                                                    ^
1 error generated.

Doing the same thing with cereal v1.3.0 (the same as the bundled version) compiles without errors.

[lkeegan]

But the bug is not in Symengine, this is a cereal bug: the v1.3.1 release didn't increment CEREAL_VERSION_PATCH

If I manually fix the patch version in my installation of cereal then symengine compiles & tests pass.

Relevant change in cereal is USCiLab/cereal@f27c12d, which is accounted for in Symengine here:

symengine/symengine/serialize-cereal.h

Lines 283 to 289 in 7b18808

	#if CEREAL_VERSION >= 10301
	std::shared_ptr<void> sharedPtr = std::static_pointer_cast<void>(
	std::make_shared<RCP<const Basic>>(ptr));
	uint32_t id = ar.registerSharedPointer(sharedPtr);
	#else
	uint32_t id = ar.registerSharedPointer(ptr.get());
	#endif

)

[lkeegan]

This can now be resolved by updating the external cereal version to v1.3.2