diff options
Diffstat (limited to 'libcxx/include/__bit/bit_log2.h')
| -rw-r--r-- | libcxx/include/__bit/bit_log2.h | 2 |
1 files changed, 2 insertions, 0 deletions
diff --git a/libcxx/include/__bit/bit_log2.h b/libcxx/include/__bit/bit_log2.h index 8077cd91d6fd..9ceeec1b2bc9 100644 --- a/libcxx/include/__bit/bit_log2.h +++ b/libcxx/include/__bit/bit_log2.h @@ -9,6 +9,7 @@ #ifndef _LIBCPP___BIT_BIT_LOG2_H #define _LIBCPP___BIT_BIT_LOG2_H +#include <__assert> #include <__bit/countl.h> #include <__config> #include <__type_traits/integer_traits.h> @@ -23,6 +24,7 @@ _LIBCPP_BEGIN_NAMESPACE_STD template <class _Tp> _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 _Tp __bit_log2(_Tp __t) _NOEXCEPT { static_assert(__is_unsigned_integer_v<_Tp>, "__bit_log2 requires an unsigned integer type"); + _LIBCPP_ASSERT_INTERNAL(__t != 0, "logarithm of 0 is undefined"); return numeric_limits<_Tp>::digits - 1 - std::__countl_zero(__t); } |