llvm/llvm-project
Vedi su GitHub[clang-tidy] New check for static_cast of an enum class type
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#71.543 aperta il 7 nov 2023
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Descrizione
When casting an enum class type using static_cast<T>, this may result in a bug if the type T is not correct. In c++23 we have std::to_underlying which should be used instead. This also is more desirable because if the enum's underlying type is changed later, the casting code is automatically still correct without the need to make the change there, too.
// Fix, must add, if not already present:
#include <utility> // Provides std::to_underlying()
// NOLINTNEXTLINE(performance-enum-size)
enum class EType : int {};
auto main() -> int
{
// NOLINTNEXTLINE(readability-magic-numbers)
EType e {42};
[[maybe_unused]]
// c++23 and later only
// Original code:
// auto i = static_cast<int>(e);
// ~~~~~~~~~~~~~~~~
// ^ bugprone: use std::to_underlying
// Fix:
auto i = std::to_underlying(e);
return 0;
}