Declared but undefined copy assignment operator for iox::expected

[pbarone-latai]

Required information

Operating system:
Ubuntu 20.04.6 LTS

Compiler version:
Clang 11

Eclipse iceoryx version:
master

Observed result or behaviour:

iox::expected has a copy and a move assignment operator declared here:

iceoryx/iceoryx_hoofs/vocabulary/include/iox/expected.hpp

Lines 166 to 174 in 4739ffd

	/// @brief calls the copy assignment operator of the contained success value
	/// or the error value - depending on what is stored in the expected
	expected& operator=(const expected&) noexcept;
	/// @brief calls the move assignment operator of the contained success value
	/// or the error value - depending on what is stored in the expected
	/// @note The move assignment operator does not explicitly invalidate the moved-from object but relies on the move
	/// assignment operator of ValueType or ErrorType to correctly invalidate the stored object
	expected& operator=(expected&& rhs) noexcept;

however, only the move assignment operator is defined

iceoryx/iceoryx_hoofs/vocabulary/include/iox/detail/expected.inl

Lines 111 to 121 in 4739ffd

	template <typename ValueType, typename ErrorType>
	inline expected<ValueType, ErrorType>&
	expected<ValueType, ErrorType>::operator=(expected<ValueType, ErrorType>&& rhs) noexcept
	{
	// AXIVION Next Construct AutosarC++19_03-M0.1.2, AutosarC++19_03-M0.1.9, FaultDetection-DeadBranches : False positive. Check needed to avoid self assignment.
	if (this != &rhs)
	{
	m_store = std::move(rhs.m_store);
	}
	return *this;
	}

As a result, a linker error is generated when attempting to run the following snippet ...

TEST_CASE("Test")
{
  iox::expected<void, int> a = iox::ok();
  iox::expected<void, int> b = iox::err(1);
  a = b;
}

ld.lld: error: undefined symbol: iox::expected<void, int>::operator=(iox::expected<void, int> const&)
>>> referenced by estimator_lib_test.cc
>>>               <REDACTED PATH>test.o:(C_A_T_C_H_T_E_S_T_2())
clang-11: error: linker command failed with exit code 1 (use -v to see invocation)

Expected result or behaviour:
No compiler error

Conditions where it occurred / Performed steps:
See above

[elfenpiff]

@pbarone-latai Whoopsie. How did that happen.

Thanks for the finding, I will take care of this.