boostorg/endian
1
0
Fork 1
mirror of https://github.com/boostorg/endian.git synced 2025-08-02 22:14:29 +02:00
Code Issues Packages Projects Releases Wiki Activity

Shifting a negative number is an -fsanitize=undefined violation, use the unsigned type

Browse Source
This commit is contained in:
Peter Dimov
2017-12-22 16:24:21 +02:00
parent 69f5b950a2
commit 134b225378
1 changed files with 15 additions and 4 deletions
Download Patch File Download Diff File Expand all files Collapse all files

19
include/boost/endian/buffers.hpp
View File

@@ -38,6 +38,10 @@
#include <boost/predef/detail/endian_compat.h>
#include <boost/endian/conversion.hpp>
#include <boost/type_traits/is_signed.hpp>
#include <boost/type_traits/make_unsigned.hpp>
#include <boost/type_traits/conditional.hpp>
#include <boost/type_traits/is_integral.hpp>
#include <boost/type_traits/type_identity.hpp>
#include <boost/cstdint.hpp>
#include <boost/static_assert.hpp>
#include <boost/core/scoped_enum.hpp>
@@ -221,20 +225,27 @@ namespace endian
{
typedef unrolled_byte_loops<T, n_bytes - 1, sign> next;
// shifting a negative number is flagged by -fsanitize=undefined
// so use the corresponding unsigned type for the shifts
typedef typename boost::conditional<
boost::is_integral<T>::value,
boost::make_unsigned<T>, boost::type_identity<T> >::type::type U;
static T load_big(const unsigned char* bytes) BOOST_NOEXCEPT
{ return static_cast<T>(*(bytes - 1) | (next::load_big(bytes - 1) << 8)); }
{ return static_cast<T>(*(bytes - 1) | (static_cast<U>(next::load_big(bytes - 1)) << 8)); }
static T load_little(const unsigned char* bytes) BOOST_NOEXCEPT
{ return static_cast<T>(*bytes | (next::load_little(bytes + 1) << 8)); }
{ return static_cast<T>(*bytes | (static_cast<U>(next::load_little(bytes + 1)) << 8)); }
static void store_big(char* bytes, T value) BOOST_NOEXCEPT
{
*(bytes - 1) = static_cast<char>(value);
next::store_big(bytes - 1, static_cast<T>(value >> 8));
next::store_big(bytes - 1, static_cast<T>(static_cast<U>(value) >> 8));
}
static void store_little(char* bytes, T value) BOOST_NOEXCEPT
{
*bytes = static_cast<char>(value);
next::store_little(bytes + 1, static_cast<T>(value >> 8));
next::store_little(bytes + 1, static_cast<T>(static_cast<U>(value) >> 8));
}
};