commit 27a396db4fd2e9734dab63d203fb354084e2c237 (tree)
parent 4edebf40d53c7e69afd088c9967f13ab8aafe1fd
Author: Alex Rønne Petersen <alex@alexrp.com>
Date: Wed, 15 Oct 2025 00:24:35 +0200
Merge pull request #25572 from alexrp/libcxx-backports
`libcxx`: backport llvm/llvm-project#155476, llvm/llvm-project#147389, llvm/llvm-project#155786
Diffstat:
6 files changed, 67 insertions(+), 15 deletions(-)
diff --git a/lib/libcxx/include/__algorithm/sort.h b/lib/libcxx/include/__algorithm/sort.h
@@ -860,6 +860,9 @@ __sort<__less<long double>&, long double*>(long double*, long double*, __less<lo
template <class _AlgPolicy, class _RandomAccessIterator, class _Comp>
_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 void
__sort_dispatch(_RandomAccessIterator __first, _RandomAccessIterator __last, _Comp& __comp) {
+ if (__first == __last) // log(0) is undefined, so don't try computing the depth
+ return;
+
typedef typename iterator_traits<_RandomAccessIterator>::difference_type difference_type;
difference_type __depth_limit = 2 * std::__bit_log2(std::__to_unsigned_like(__last - __first));
diff --git a/lib/libcxx/include/__bit/bit_log2.h b/lib/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);
}
diff --git a/lib/libcxx/include/__functional/hash.h b/lib/libcxx/include/__functional/hash.h
@@ -21,6 +21,7 @@
#include <__type_traits/is_enum.h>
#include <__type_traits/is_floating_point.h>
#include <__type_traits/is_integral.h>
+#include <__type_traits/is_unqualified.h>
#include <__type_traits/underlying_type.h>
#include <__utility/pair.h>
#include <__utility/swap.h>
@@ -355,7 +356,8 @@ struct __hash_impl {
};
template <class _Tp>
-struct __hash_impl<_Tp, __enable_if_t<is_enum<_Tp>::value> > : __unary_function<_Tp, size_t> {
+struct __hash_impl<_Tp, __enable_if_t<is_enum<_Tp>::value && __is_unqualified_v<_Tp> > >
+ : __unary_function<_Tp, size_t> {
_LIBCPP_HIDE_FROM_ABI size_t operator()(_Tp __v) const _NOEXCEPT {
using type = __underlying_type_t<_Tp>;
return hash<type>()(static_cast<type>(__v));
@@ -363,17 +365,21 @@ struct __hash_impl<_Tp, __enable_if_t<is_enum<_Tp>::value> > : __unary_function<
};
template <class _Tp>
-struct __hash_impl<_Tp, __enable_if_t<is_integral<_Tp>::value && (sizeof(_Tp) <= sizeof(size_t))> >
+struct __hash_impl<
+ _Tp,
+ __enable_if_t<is_integral<_Tp>::value && __is_unqualified_v<_Tp> && (sizeof(_Tp) <= sizeof(size_t))> >
: __unary_function<_Tp, size_t> {
_LIBCPP_HIDE_FROM_ABI size_t operator()(_Tp __v) const _NOEXCEPT { return static_cast<size_t>(__v); }
};
template <class _Tp>
-struct __hash_impl<_Tp, __enable_if_t<is_integral<_Tp>::value && (sizeof(_Tp) > sizeof(size_t))> >
+struct __hash_impl<_Tp,
+ __enable_if_t<is_integral<_Tp>::value && __is_unqualified_v<_Tp> && (sizeof(_Tp) > sizeof(size_t))> >
: __scalar_hash<_Tp> {};
template <class _Tp>
-struct __hash_impl<_Tp, __enable_if_t<is_floating_point<_Tp>::value> > : __scalar_hash<_Tp> {
+struct __hash_impl<_Tp, __enable_if_t<is_floating_point<_Tp>::value && __is_unqualified_v<_Tp> > >
+ : __scalar_hash<_Tp> {
_LIBCPP_HIDE_FROM_ABI size_t operator()(_Tp __v) const _NOEXCEPT {
// -0.0 and 0.0 should return same hash
if (__v == 0.0f)
diff --git a/lib/libcxx/include/__type_traits/is_unqualified.h b/lib/libcxx/include/__type_traits/is_unqualified.h
@@ -0,0 +1,25 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___TYPE_TRAITS_IS_UNQUALIFIED_H
+#define _LIBCPP___TYPE_TRAITS_IS_UNQUALIFIED_H
+
+#include <__config>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <class _Tp>
+inline const bool __is_unqualified_v = __is_same(_Tp, __remove_cvref(_Tp));
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___TYPE_TRAITS_IS_UNQUALIFIED_H
diff --git a/lib/libcxx/include/fstream b/lib/libcxx/include/fstream
@@ -821,6 +821,14 @@ typename basic_filebuf<_CharT, _Traits>::int_type basic_filebuf<_CharT, _Traits>
template <class _CharT, class _Traits>
typename basic_filebuf<_CharT, _Traits>::int_type basic_filebuf<_CharT, _Traits>::overflow(int_type __c) {
+ auto __failed = [this]() {
+ if (this->pptr() == this->epptr() + 1) {
+ this->pbump(-1); // lose the character we overflowed above -- we don't really have a
+ // choice since we couldn't commit the contents of the put area
+ }
+ return traits_type::eof();
+ };
+
if (__file_ == nullptr)
return traits_type::eof();
__write_mode();
@@ -841,8 +849,9 @@ typename basic_filebuf<_CharT, _Traits>::int_type basic_filebuf<_CharT, _Traits>
if (__always_noconv_) {
size_t __n = static_cast<size_t>(this->pptr() - this->pbase());
- if (std::fwrite(this->pbase(), sizeof(char_type), __n, __file_) != __n)
- return traits_type::eof();
+ if (std::fwrite(this->pbase(), sizeof(char_type), __n, __file_) != __n) {
+ return __failed();
+ }
} else {
if (!__cv_)
std::__throw_bad_cast();
@@ -854,34 +863,38 @@ typename basic_filebuf<_CharT, _Traits>::int_type basic_filebuf<_CharT, _Traits>
char* __extbuf_end = __extbuf_;
do {
codecvt_base::result __r = __cv_->out(__st_, __b, __p, __end, __extbuf_, __extbuf_ + __ebs_, __extbuf_end);
- if (__end == __b)
- return traits_type::eof();
+ if (__end == __b) {
+ return __failed();
+ }
// No conversion needed: output characters directly to the file, done.
if (__r == codecvt_base::noconv) {
size_t __n = static_cast<size_t>(__p - __b);
- if (std::fwrite(__b, 1, __n, __file_) != __n)
- return traits_type::eof();
+ if (std::fwrite(__b, 1, __n, __file_) != __n) {
+ return __failed();
+ }
break;
// Conversion successful: output the converted characters to the file, done.
} else if (__r == codecvt_base::ok) {
size_t __n = static_cast<size_t>(__extbuf_end - __extbuf_);
- if (std::fwrite(__extbuf_, 1, __n, __file_) != __n)
- return traits_type::eof();
+ if (std::fwrite(__extbuf_, 1, __n, __file_) != __n) {
+ return __failed();
+ }
break;
// Conversion partially successful: output converted characters to the file and repeat with the
// remaining characters.
} else if (__r == codecvt_base::partial) {
size_t __n = static_cast<size_t>(__extbuf_end - __extbuf_);
- if (std::fwrite(__extbuf_, 1, __n, __file_) != __n)
- return traits_type::eof();
+ if (std::fwrite(__extbuf_, 1, __n, __file_) != __n) {
+ return __failed();
+ }
__b = const_cast<char_type*>(__end);
continue;
} else {
- return traits_type::eof();
+ return __failed();
}
} while (true);
}
diff --git a/lib/libcxx/src/algorithm.cpp b/lib/libcxx/src/algorithm.cpp
@@ -13,6 +13,9 @@ _LIBCPP_BEGIN_NAMESPACE_STD
template <class Comp, class RandomAccessIterator>
void __sort(RandomAccessIterator first, RandomAccessIterator last, Comp comp) {
+ if (first == last) // log(0) is undefined, so don't try computing the depth
+ return;
+
auto depth_limit = 2 * std::__bit_log2(static_cast<size_t>(last - first));
// Only use bitset partitioning for arithmetic types. We should also check
