Fix MSVC compilation error on EVMVersion comparison

[gmh5225]

No description provided.

[github-actions]

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[r0qs]

Hi @gmh5225, thank you for your contribution. Could you please clarify what kind of compilation error you encountered on MSVC? The changes in the PR seem unnecessary to me.

The EVMVersion class implements comparability by inheriting from boost::less_than_comparable and boost::equality_comparable. These templates provide comparison operators such as >, <=, and >=, derived from the definitions of operator< and operator==. See:

solidity/liblangutil/EVMVersion.h

Lines 47 to 49 in 13943d9

	class EVMVersion:
	boost::less_than_comparable<EVMVersion>,
	boost::equality_comparable<EVMVersion>

solidity/liblangutil/EVMVersion.h

Lines 98 to 99 in 13943d9

	bool operator==(EVMVersion const& _other) const { return m_version == _other.m_version; }
	bool operator<(EVMVersion const& _other) const { return m_version < _other.m_version; }

Maybe it is a Boost-related issue? Could you please provide some description of the problem you are facing so we can better understand and address it?

[gmh5225]

The error is: solidity\liblangutil\EVMVersion.cpp(32,2): error C2676: binary '>=': 'const solidity::langutil::EVMVersion::Version' does not define this operator or a conversion to a type acceptable to the predefined operator

The issue is not Boost-related. While the class has overloaded operator== and operator<, it doesn't have an overloaded operator>=.

The issue can be reproduced in Debug mode with MSVC.

@r0qs

[cameel]

This is comparing the object with a number. We don't have an operator defined for that so it must be working only due to some implicit conversion. Not sure why only MSVC would be choking on that, probably some subtle implementation difference between compilers, but a cleaner way to fix it would be something like: *this >= prague().