diff options
Diffstat (limited to 'libcxx/include/__config')
| -rw-r--r-- | libcxx/include/__config | 27 |
1 files changed, 20 insertions, 7 deletions
diff --git a/libcxx/include/__config b/libcxx/include/__config index b9203e640a3e..51b100fa5569 100644 --- a/libcxx/include/__config +++ b/libcxx/include/__config @@ -134,6 +134,15 @@ # define _LIBCPP_ABI_DO_NOT_EXPORT_VECTOR_BASE_COMMON // According to the Standard, `bitset::operator[] const` returns bool # define _LIBCPP_ABI_BITSET_VECTOR_BOOL_CONST_SUBSCRIPT_RETURN_BOOL +// Fix the implementation of CityHash used for std::hash<fundamental-type>. +// This is an ABI break because `std::hash` will return a different result, +// which means that hashing the same object in translation units built against +// different versions of libc++ can return inconsistent results. This is especially +// tricky since std::hash is used in the implementation of unordered containers. +// +// The incorrect implementation of CityHash has the problem that it drops some +// bits on the floor. +# define _LIBCPP_ABI_FIX_CITYHASH_IMPLEMENTATION // Remove the base 10 implementation of std::to_chars from the dylib. // The implementation moved to the header, but we still export the symbols from // the dylib for backwards compatibility. @@ -629,7 +638,11 @@ typedef __char32_t char32_t; # else # define _LIBCPP_HIDE_FROM_ABI _LIBCPP_HIDDEN _LIBCPP_EXCLUDE_FROM_EXPLICIT_INSTANTIATION # endif -# define _LIBCPP_HIDE_FROM_ABI_VIRTUAL _LIBCPP_HIDDEN _LIBCPP_EXCLUDE_FROM_EXPLICIT_INSTANTIATION +# define _LIBCPP_HIDE_FROM_ABI_VIRTUAL _LIBCPP_HIDDEN _LIBCPP_EXCLUDE_FROM_EXPLICIT_INSTANTIATION + +// This macro provides a HIDE_FROM_ABI equivalent that can be applied to extern +// "C" function, as those lack mangling. +# define _LIBCPP_HIDE_FROM_ABI_C _LIBCPP_HIDDEN _LIBCPP_EXCLUDE_FROM_EXPLICIT_INSTANTIATION # ifdef _LIBCPP_BUILDING_LIBRARY # if _LIBCPP_ABI_VERSION > 1 @@ -1223,12 +1236,12 @@ _LIBCPP_BEGIN_NAMESPACE_STD _LIBCPP_END_NAMESPACE_STD // functions are declared by the C library. # define _LIBCPP_HAS_NO_C8RTOMB_MBRTOC8 // GNU libc 2.36 and newer declare c8rtomb() and mbrtoc8() in C++ modes if -// __cpp_char8_t is defined or if C2X extensions are enabled. Unfortunately, -// determining the latter depends on internal GNU libc details. If the -// __cpp_char8_t feature test macro is not defined, then a char8_t typedef -// will be declared as well. -# if defined(_LIBCPP_GLIBC_PREREQ) && defined(__GLIBC_USE) -# if _LIBCPP_GLIBC_PREREQ(2, 36) && (defined(__cpp_char8_t) || __GLIBC_USE(ISOC2X)) +// __cpp_char8_t is defined or if C2X extensions are enabled. Determining +// the latter depends on internal GNU libc details that are not appropriate +// to depend on here, so any declarations present when __cpp_char8_t is not +// defined are ignored. +# if defined(_LIBCPP_GLIBC_PREREQ) +# if _LIBCPP_GLIBC_PREREQ(2, 36) && defined(__cpp_char8_t) # undef _LIBCPP_HAS_NO_C8RTOMB_MBRTOC8 # endif # endif |