[PATCH v3] libstdc++: Cleanup and stabilize format _Spec<_CharT> and _Pres_type.
Tomasz Kaminski
tkaminsk@redhat.com
Tue Apr 29 11:07:20 GMT 2025
On Tue, Apr 29, 2025 at 12:58 PM Tomasz Kaminski <tkaminsk@redhat.com>
wrote:
>
>
> On Tue, Apr 29, 2025 at 9:28 AM Tomasz Kamiński <tkaminsk@redhat.com>
> wrote:
>
>> These patch makes following changes to _Pres_type values:
>> * _Pres_esc is replaced with separate _M_debug flag.
>> * _Pres_s, _Pres_p do not overlap with _Pres_none.
>> * hexadecimal presentation use same values for pointer, integer
>> and floating point types.
>>
>> Instead of `_M_reserved` and `_M_reserved2` bitfields, the members of
>> _Spec<_CharT> are rearranged so the class contains 16bit of tail padding.
>> Derived classes (like _ChronoSpec<_CharT>) can reuse the storage for
>> initial
>> members. We also add _SpecBase as the base class for _Spec<_CharT> to make
>> it non-C++98 POD, which allows tail padding to be reused on Itanium ABI.
>>
>> Finally, the format enumerators are defined as enum class with unsigned
>> char as underlying type, followed by using enum to bring names in scope.
>> _Term_char was adjusted for consistency.
>>
>> The '?' is changed to separate _M_debug flag, to allow debug format to be
>> independent from the presentation type, and applied to multiple
>> presentation
>> types. For example it could be used to trigger memberwise or reflection
>> based
>> formatting.
>>
>> The _M_format_character and _M_format_character_escaped functions are
>> merged
>> to single function that handle normal and debug presentation. In
>> particular
>> this would allow future support for '?c' for printing integer types as
>> escaped
>> character. _S_character_width is also folded in the merged function.
>>
>> Decoupling _Pres_s value from _Pres_none, allows it to be used for string
>> presentation for range formatting, and removes the need for separate
>> _Pres_seq
>> and _Pres_str. This does not affect formatting of bool as
>> __formatter_int::_M_parse
>> overrides default value of _M_type. And with separation of the _M_debug
>> flag,
>> __formatter_str::format behavior is now agnostic to _M_type value.
>>
>> The values for integer presentation types, are arranged so textual
>> presentations
>> (_Prec_s, _Pres_c) are grouped together. For consistency floating point
>> hexadecimal presentation uses the same values as integer ones.
>>
>> New _Pres_p and setting for _M_alt enables using some spec to configure
>> formatting
>> of uintptr_t with __formatter_int, and const void* with __formatter_ptr.
>> Differentiating it from _Pres_none would allow future of formatter<T*,
>> _CharT>
>> that would require explicit presentation type to be specified. This would
>> allow
>> std::vector<T*> to be formatter directly with '{::p}' format spec.
>>
>> The constructors for __formatter_int and _formatter_ptr from
>> _Spec<_CharT>,
>> now also set default presentation modes, as format functions expects them.
>>
>> libstdc++-v3/ChangeLog:
>>
>> * include/bits/chrono_io.h
>> (_ChronoSpec<_CharT>::_M_locale_specific):
>> Declare as bit filed in tail-padding..
>> * include/bits/formatfwd.h (__format::_Align): Defined as enum
>> class
>> and add using enum.
>> * include/std/format (__format::_Pres_type, __format::_Sign)
>> (__format::_WidthPrec, __format::_Arg_t): Defined as enum class
>> and
>> add using enum.
>> (_Pres_type::_Pres_esc): Replace with _Pres_max.
>> (_Pres_type::_Pres_seq, _Pres_type::_Pres_str): Remove.
>> (__format::_Pres_type): Updated values of enumerators as
>> described above.
>> (_Spec<_CharT>): Rearranged members to have 16bits of
>> tail-padding.
>> (_Spec<_CharT>::_M_debug): Defined.
>> (_Spec<_CharT>::_M_reserved, _Spec<_CharT>::_M_reserved2):
>> Removed.
>> (_Spec<_CharT>::_M_parse_fill_and_align,
>> _Spec<_CharT>::_M_parse_sign)
>> (__format::__write_padded_as_spec): Adjusted default value checks.
>> (__format::_Term_char): Add using enum and rename enumertors.
>> (__format::__should_escape_ascii): Adjusted _Term_char uses.
>> (__formatter_str<_CharT>::parse): Set _Pres_s if specifed and
>> _M_debug
>> instead of _Pres_esc.
>> (__formatter_str<_CharT>::set_debug_format): Set _M_debug instead
>> of
>> _Pres_esc.
>> (__formatter_str<_CharT>::format,
>> __formatter_str<_CharT>::_M_format_range):
>> Check _M_debug instead of _Prec_esc.
>> (__formatter_str<_CharT>::_M_format_escaped): Adjusted _Term_char
>> uses.
>> (__formatter_int<_CharT>::__formatter_int(_Spec<_CharT>)): Set
>> _Pres_d if
>> default presentation type is not set.
>> (__formatter_int<_CharT>::_M_parse): Adjusted default value
>> checks.
>> (__formatter_int<_CharT>::_M_do_parse): Set _M_debug instead of
>> _Pres_esc.
>> (__formatter_int<_CharT>::_M_format_character): Handle escaped
>> presentation.
>> (__formatter_int<_CharT>::_M_format_character_escaped)
>> (__formatter_int<_CharT>::_S_character_width): Merged into
>> _M_format_character.
>> (__formatter_ptr<_CharT>::__formatter_ptr(_Spec<_CharT>)): Set
>> _Pres_p if default
>> presentation type is not set.
>> (__formatter_ptr<_CharT>::parse): Add default __type parameter,
>> store _Pres_p,
>> and handle _M_alt to be consistent with meaning for integers.
>> (__foramtter_ptr<_CharT>::_M_set_default): Define.
>> (__format::__pack_arg_types, std::basic_format_args): Add
>> necessary casts.
>> (formatter<_CharT, _CharT>::set_debug_format)
>> (formatter<char, wchar_t>::set_debug_format): Set _M_debug
>> instead of _Pres_esc.
>> (formatter<_CharT, _CharT>::format, formatter<char,
>> wchar_t>::format):
>> Simplify calls to _M_format_character.
>> (range_formatter<_Rg, _CharT>::parse): Replace _Pres_str with
>> _Pres_s
>> and set _M_debug instead of _Pres_esc.
>> (range_formatter<_Rg, _CharT>::format): Replace _Pres_str with
>> _Pres_s.
>> ---
>> I think using tail-padding is the better option, so following on here.
>> Performed a few additional cleanups:
>> * _Term_char now is consitient with remaining enumerators
>> * __formatter_ptr/_formatter_int constructor from _Spec, now set
>> defaults for
>> _Pres_none, as format expects them. This makes using them like in
>> formatter<thread::id, _CharT> easier.
>> Testing on x86_64-linux. OK for turnk if test passes?
>>
> All test passed. OK for trunk?
>
This is implemented on top of one-liner fix from "libstdc++: Fix
_Padding_sink in case when predicted is between padwidth and maxwidth
[PR109162]",
so needs to be merged after.
>
>> libstdc++-v3/include/bits/chrono_io.h | 18 +--
>> libstdc++-v3/include/bits/formatfwd.h | 3 +-
>> libstdc++-v3/include/std/format | 221 ++++++++++++++------------
>> 3 files changed, 123 insertions(+), 119 deletions(-)
>>
>> diff --git a/libstdc++-v3/include/bits/chrono_io.h
>> b/libstdc++-v3/include/bits/chrono_io.h
>> index b7f6f5f49e5..2b77eb2acc5 100644
>> --- a/libstdc++-v3/include/bits/chrono_io.h
>> +++ b/libstdc++-v3/include/bits/chrono_io.h
>> @@ -207,21 +207,15 @@ namespace __format
>> template<typename _CharT>
>> struct _ChronoSpec : _Spec<_CharT>
>> {
>> - basic_string_view<_CharT> _M_chrono_specs;
>> -
>> - // Use one of the reserved bits in __format::_Spec<C>.
>> + // Placed in tail-padding of __format::_Spec<C>.
>> // This indicates that a locale-dependent conversion specifier
>> such as
>> // %a is used in the chrono-specs. This is not the same as the
>> // _Spec<C>::_M_localized member which indicates that "L" was
>> present
>> // in the format-spec, e.g. "{:L%a}" is localized and
>> locale-specific,
>> // but "{:L}" is only localized and "{:%a}" is only
>> locale-specific.
>> - constexpr bool
>> - _M_locale_specific() const noexcept
>> - { return this->_M_reserved; }
>> + unsigned _M_locale_specific : 1;
>>
>> - constexpr void
>> - _M_locale_specific(bool __b) noexcept
>> - { this->_M_reserved = __b; }
>> + basic_string_view<_CharT> _M_chrono_specs;
>> };
>>
>> // Represents the information provided by a chrono type.
>> @@ -488,7 +482,7 @@ namespace __format
>> _M_spec = __spec;
>> _M_spec._M_chrono_specs
>> = __string_view(__chrono_specs, __first -
>> __chrono_specs);
>> - _M_spec._M_locale_specific(__locale_specific);
>> + _M_spec._M_locale_specific = __locale_specific;
>>
>> return __first;
>> }
>> @@ -514,7 +508,7 @@ namespace __format
>> // of chrono types is underspecified
>> if constexpr (is_same_v<_CharT, char>)
>> if constexpr (__unicode::__literal_encoding_is_utf8())
>> - if (_M_spec._M_localized && _M_spec._M_locale_specific())
>> + if (_M_spec._M_localized && _M_spec._M_locale_specific)
>> {
>> extern locale __with_encoding_conversion(const locale&);
>>
>> @@ -816,7 +810,7 @@ namespace __format
>> // of chrono types is underspecified
>> if constexpr (is_same_v<_CharT, char>)
>> if constexpr (__unicode::__literal_encoding_is_utf8())
>> - if (_M_spec._M_localized && _M_spec._M_locale_specific()
>> + if (_M_spec._M_localized && _M_spec._M_locale_specific
>> && __loc != locale::classic())
>> {
>> extern string_view
>> diff --git a/libstdc++-v3/include/bits/formatfwd.h
>> b/libstdc++-v3/include/bits/formatfwd.h
>> index 3fa01ad1eab..777e6290f74 100644
>> --- a/libstdc++-v3/include/bits/formatfwd.h
>> +++ b/libstdc++-v3/include/bits/formatfwd.h
>> @@ -71,12 +71,13 @@ namespace __format
>> concept __char = same_as<_CharT, char>;
>> #endif
>>
>> - enum _Align {
>> + enum class _Align : unsigned char {
>> _Align_default,
>> _Align_left,
>> _Align_right,
>> _Align_centre,
>> };
>> + using enum _Align;
>>
>> template<typename _CharT> struct _Spec;
>>
>> diff --git a/libstdc++-v3/include/std/format
>> b/libstdc++-v3/include/std/format
>> index b3794b64b59..0be214b8713 100644
>> --- a/libstdc++-v3/include/std/format
>> +++ b/libstdc++-v3/include/std/format
>> @@ -472,30 +472,33 @@ namespace __format
>> return {0, nullptr};
>> }
>>
>> - enum _Pres_type {
>> + enum class _Pres_type : unsigned char {
>> _Pres_none = 0, // Default type (not valid for integer presentation
>> types).
>> + _Pres_s = 1, // For strings, bool, ranges
>> // Presentation types for integral types (including bool and charT).
>> - _Pres_d = 1, _Pres_b, _Pres_B, _Pres_o, _Pres_x, _Pres_X, _Pres_c,
>> - // Presentation types for floating-point types.
>> - _Pres_a = 1, _Pres_A, _Pres_e, _Pres_E, _Pres_f, _Pres_F, _Pres_g,
>> _Pres_G,
>> - _Pres_p = 0, _Pres_P, // For pointers.
>> - _Pres_s = 0, // For strings, bool
>> - _Pres_seq = 0, _Pres_str, // For ranges
>> - _Pres_esc = 0xf, // For strings, charT and ranges
>> + /* s */ _Pres_c = 2, _Pres_x, _Pres_X, _Pres_d, _Pres_o, _Pres_b,
>> _Pres_B,
>> + // Presentation types for floating-point types
>> + _Pres_g = 1, _Pres_G, _Pres_a, _Pres_A, _Pres_e, _Pres_E, _Pres_f,
>> _Pres_F,
>> + // For pointers, the value are same as hexadecimal presentations for
>> integers
>> + _Pres_p = _Pres_x, _Pres_P = _Pres_X,
>> + _Pres_max = 0xf,
>> };
>> + using enum _Pres_type;
>>
>> - enum _Sign {
>> + enum class _Sign : unsigned char {
>> _Sign_default,
>> _Sign_plus,
>> _Sign_minus, // XXX does this need to be distinct from
>> _Sign_default?
>> _Sign_space,
>> };
>> + using enum _Sign;
>>
>> - enum _WidthPrec {
>> + enum _WidthPrec : unsigned char {
>> _WP_none, // No width/prec specified.
>> _WP_value, // Fixed width/prec specified.
>> _WP_from_arg // Use a formatting argument for width/prec.
>> };
>> + using enum _WidthPrec;
>>
>> template<typename _Context>
>> size_t
>> @@ -507,9 +510,17 @@ namespace __format
>> constexpr bool __is_xdigit(char __c)
>> { return std::__detail::__from_chars_alnum_to_val(__c) < 16; }
>>
>> + // Used to make _Spec a non-C++98 POD, so the tail-padding is used.
>> + // https://itanium-cxx-abi.github.io/cxx-abi/abi.html#pod
>> + struct _SpecBase
>> + { };
>> +
>> template<typename _CharT>
>> - struct _Spec
>> + struct _Spec : _SpecBase
>> {
>> + unsigned short _M_width;
>> + unsigned short _M_prec;
>> + char32_t _M_fill = ' ';
>> _Align _M_align : 2;
>> _Sign _M_sign : 2;
>> unsigned _M_alt : 1;
>> @@ -517,12 +528,10 @@ namespace __format
>> unsigned _M_zero_fill : 1;
>> _WidthPrec _M_width_kind : 2;
>> _WidthPrec _M_prec_kind : 2;
>> + unsigned _M_debug : 1;
>> _Pres_type _M_type : 4;
>> - unsigned _M_reserved : 1;
>> - unsigned _M_reserved2 : 16;
>> - unsigned short _M_width;
>> - unsigned short _M_prec;
>> - char32_t _M_fill = ' ';
>> + // This class has 16bit of tail padding, that can be used by
>> + // derived classes.
>>
>> using iterator = typename basic_string_view<_CharT>::iterator;
>>
>> @@ -562,7 +571,7 @@ namespace __format
>> char32_t __c = *__beg++;
>> if (__is_scalar_value(__c))
>> if (auto __next = __beg.base(); __next != __last)
>> - if (_Align __align = _S_align(*__next))
>> + if (_Align __align = _S_align(*__next); __align !=
>> _Align_default)
>> {
>> _M_fill = __c;
>> _M_align = __align;
>> @@ -571,14 +580,14 @@ namespace __format
>> }
>> }
>> else if (__last - __first >= 2)
>> - if (_Align __align = _S_align(__first[1]))
>> + if (_Align __align = _S_align(__first[1]); __align !=
>> _Align_default)
>> {
>> _M_fill = *__first;
>> _M_align = __align;
>> return __first + 2;
>> }
>>
>> - if (_Align __align = _S_align(__first[0]))
>> + if (_Align __align = _S_align(__first[0]); __align !=
>> _Align_default)
>> {
>> _M_fill = ' ';
>> _M_align = __align;
>> @@ -603,7 +612,7 @@ namespace __format
>> constexpr iterator
>> _M_parse_sign(iterator __first, iterator) noexcept
>> {
>> - if (_Sign __sign = _S_sign(*__first))
>> + if (_Sign __sign = _S_sign(*__first); __sign != _Sign_default)
>> {
>> _M_sign = __sign;
>> return __first + 1;
>> @@ -871,7 +880,7 @@ namespace __format
>>
>> const size_t __nfill = __width - __estimated_width;
>>
>> - if (__spec._M_align)
>> + if (__spec._M_align != _Align_default)
>> __align = __spec._M_align;
>>
>> return __format::__write_padded(__fc.out(), __str, __align,
>> __nfill,
>> @@ -899,9 +908,10 @@ namespace __format
>>
>> // Values are indices into _Escapes::all.
>> enum class _Term_char : unsigned char {
>> - _Tc_quote = 12,
>> - _Tc_apos = 15
>> + _Term_quote = 12,
>> + _Term_apos = 15
>> };
>> + using enum _Term_char;
>>
>> template<typename _CharT>
>> struct _Escapes
>> @@ -991,9 +1001,9 @@ namespace __format
>> case _Esc::_S_bslash()[0]:
>> return true;
>> case _Esc::_S_quote()[0]:
>> - return __term == _Term_char::_Tc_quote;
>> + return __term == _Term_quote;
>> case _Esc::_S_apos()[0]:
>> - return __term == _Term_char::_Tc_apos;
>> + return __term == _Term_apos;
>> default:
>> return (__c >= 0 && __c < 0x20) || __c == 0x7f;
>> };
>> @@ -1312,11 +1322,14 @@ namespace __format
>> return __first;
>>
>> if (*__first == 's')
>> - ++__first;
>> + {
>> + __spec._M_type = _Pres_s;
>> + ++__first;
>> + }
>> #if __glibcxx_format_ranges // C++ >= 23 && HOSTED
>> else if (*__first == '?')
>> {
>> - __spec._M_type = _Pres_esc;
>> + __spec._M_debug = true;
>> ++__first;
>> }
>> #endif
>> @@ -1332,7 +1345,7 @@ namespace __format
>> format(basic_string_view<_CharT> __s,
>> basic_format_context<_Out, _CharT>& __fc) const
>> {
>> - if (_M_spec._M_type == _Pres_esc)
>> + if (_M_spec._M_debug)
>> return _M_format_escaped(__s, __fc);
>>
>> if (_M_spec._M_width_kind == _WP_none
>> @@ -1349,22 +1362,21 @@ namespace __format
>> _M_format_escaped(basic_string_view<_CharT> __s,
>> basic_format_context<_Out, _CharT>& __fc) const
>> {
>> - constexpr auto __term = __format::_Term_char::_Tc_quote;
>> const size_t __padwidth = _M_spec._M_get_width(__fc);
>> if (__padwidth == 0 && _M_spec._M_prec_kind == _WP_none)
>> - return __format::__write_escaped(__fc.out(), __s, __term);
>> + return __format::__write_escaped(__fc.out(), __s,
>> _Term_quote);
>>
>> const size_t __maxwidth = _M_spec._M_get_precision(__fc);
>> const size_t __width = __truncate(__s, __maxwidth);
>> // N.B. Escaping only increases width
>> if (__padwidth <= __width && _M_spec._M_prec_kind == _WP_none)
>> - return __format::__write_escaped(__fc.out(), __s, __term);
>> + return __format::__write_escaped(__fc.out(), __s,
>> _Term_quote);
>>
>> // N.B. [tab:format.type.string] defines '?' as
>> // Copies the escaped string ([format.string.escaped]) to the
>> output,
>> // so precision seem to appy to escaped string.
>> _Padding_sink<_Out, _CharT> __sink(__fc.out(), __padwidth,
>> __maxwidth);
>> - __format::__write_escaped(__sink.out(), __s, __term);
>> + __format::__write_escaped(__sink.out(), __s, _Term_quote);
>> return __sink._M_finish(_M_spec._M_align, _M_spec._M_fill);
>> }
>>
>> @@ -1388,7 +1400,7 @@ namespace __format
>> size_t(ranges::distance(__rg)));
>> return format(__str, __fc);
>> }
>> - else if (_M_spec._M_type != _Pres_esc)
>> + else if (!_M_spec._M_debug)
>> {
>> const size_t __padwidth = _M_spec._M_get_width(__fc);
>> if (__padwidth == 0 && _M_spec._M_prec_kind == _WP_none)
>> @@ -1441,7 +1453,7 @@ namespace __format
>>
>> constexpr void
>> set_debug_format() noexcept
>> - { _M_spec._M_type = _Pres_esc; }
>> + { _M_spec._M_debug = true; }
>> #endif
>>
>> private:
>> @@ -1462,7 +1474,10 @@ namespace __format
>> constexpr
>> __formatter_int(_Spec<_CharT> __spec) noexcept
>> : _M_spec(__spec)
>> - { }
>> + {
>> + if (_M_spec._M_type == _Pres_none)
>> + _M_spec._M_type = _Pres_d;
>> + }
>>
>> constexpr typename basic_format_parse_context<_CharT>::iterator
>> _M_do_parse(basic_format_parse_context<_CharT>& __pc, _Pres_type
>> __type)
>> @@ -1551,7 +1566,7 @@ namespace __format
>> case 's':
>> if (__type == _AsBool)
>> {
>> - __spec._M_type = _Pres_s; // same value (and meaning) as
>> "none"
>> + __spec._M_type = _Pres_s; // same meaning as "none" for
>> bool
>> ++__first;
>> }
>> break;
>> @@ -1559,7 +1574,7 @@ namespace __format
>> case '?':
>> if (__type == _AsChar)
>> {
>> - __spec._M_type = _Pres_esc;
>> + __spec._M_debug = true;
>> ++__first;
>> }
>> #endif
>> @@ -1580,7 +1595,8 @@ namespace __format
>> {
>> auto __end = _M_do_parse(__pc, _AsBool);
>> if (_M_spec._M_type == _Pres_s)
>> - if (_M_spec._M_sign || _M_spec._M_alt ||
>> _M_spec._M_zero_fill)
>> + if (_M_spec._M_sign != _Sign_default || _M_spec._M_alt
>> + || _M_spec._M_zero_fill)
>> __throw_format_error("format error: format-spec
>> contains "
>> "invalid formatting options for "
>> "'bool'");
>> @@ -1589,8 +1605,9 @@ namespace __format
>> else if constexpr (__char<_Tp>)
>> {
>> auto __end = _M_do_parse(__pc, _AsChar);
>> - if (_M_spec._M_type == _Pres_c || _M_spec._M_type ==
>> _Pres_esc)
>> - if (_M_spec._M_sign || _M_spec._M_alt ||
>> _M_spec._M_zero_fill
>> + if (_M_spec._M_type == _Pres_c)
>> + if (_M_spec._M_sign != _Sign_default || _M_spec._M_alt
>> + || _M_spec._M_zero_fill
>> /* XXX should be invalid? || _M_spec._M_localized
>> */)
>> __throw_format_error("format error: format-spec
>> contains "
>> "invalid formatting options for "
>> @@ -1702,51 +1719,34 @@ namespace __format
>> _M_spec);
>> }
>>
>> - [[__gnu__::__always_inline__]]
>> - static size_t
>> - _S_character_width(_CharT __c)
>> - {
>> - // N.B. single byte cannot encode charcter of width greater than 1
>> - if constexpr (sizeof(_CharT) > 1u &&
>> -
>> __unicode::__literal_encoding_is_unicode<_CharT>())
>> - return __unicode::__field_width(__c);
>> - else
>> - return 1u;
>> - }
>> -
>> template<typename _Out>
>> typename basic_format_context<_Out, _CharT>::iterator
>> _M_format_character(_CharT __c,
>> - basic_format_context<_Out, _CharT>& __fc) const
>> + basic_format_context<_Out, _CharT>& __fc)
>> const
>> {
>> - return __format::__write_padded_as_spec({&__c, 1u},
>> - _S_character_width(__c),
>> - __fc, _M_spec);
>> - }
>> + basic_string_view<_CharT> __in(&__c, 1u);
>> + size_t __width = 1u;
>> + // N.B. single byte cannot encode charcter of width greater
>> than 1
>> + if constexpr (sizeof(_CharT) > 1u &&
>> +
>> __unicode::__literal_encoding_is_unicode<_CharT>())
>> + __width = __unicode::__field_width(__c);
>>
>> - template<typename _Out>
>> - typename basic_format_context<_Out, _CharT>::iterator
>> - _M_format_character_escaped(_CharT __c,
>> - basic_format_context<_Out, _CharT>&
>> __fc) const
>> - {
>> - using _Esc = _Escapes<_CharT>;
>> - constexpr auto __term = __format::_Term_char::_Tc_apos;
>> - const basic_string_view<_CharT> __in(&__c, 1u);
>> - if (_M_spec._M_get_width(__fc) <= 3u)
>> - return __format::__write_escaped(__fc.out(), __in, __term);
>> + if (!_M_spec._M_debug)
>> + return __format::__write_padded_as_spec(__in, __width,
>> + __fc, _M_spec);
>> +
>> + __width += 2;
>> + if (_M_spec._M_get_width(__fc) <= __width)
>> + return __format::__write_escaped(__fc.out(), __in,
>> _Term_apos);
>>
>> _CharT __buf[12];
>> __format::_Fixedbuf_sink<_CharT> __sink(__buf);
>> - __format::__write_escaped(__sink.out(), __in, __term);
>> + __format::__write_escaped(__sink.out(), __in, _Term_apos);
>>
>> - const basic_string_view<_CharT> __escaped = __sink.view();
>> - size_t __estimated_width;
>> - if (__escaped[1] == _Esc::_S_bslash()[0]) // escape sequence
>> - __estimated_width = __escaped.size();
>> - else
>> - __estimated_width = 2 + _S_character_width(__c);
>> - return __format::__write_padded_as_spec(__escaped,
>> - __estimated_width,
>> + __in = __sink.view();
>> + if (__in[1] == _Escapes<_CharT>::_S_bslash()[0]) // escape
>> sequence
>> + __width = __in.size();
>> + return __format::__write_padded_as_spec(__in, __width,
>> __fc, _M_spec);
>> }
>>
>> @@ -2419,17 +2419,18 @@ namespace __format
>> constexpr
>> __formatter_ptr(_Spec<_CharT> __spec) noexcept
>> : _M_spec(__spec)
>> - { }
>> + { _M_set_default(_Pres_p); }
>>
>> constexpr typename basic_format_parse_context<_CharT>::iterator
>> - parse(basic_format_parse_context<_CharT>& __pc)
>> + parse(basic_format_parse_context<_CharT>& __pc, _Pres_type __type
>> = _Pres_p)
>> {
>> __format::_Spec<_CharT> __spec{};
>> const auto __last = __pc.end();
>> auto __first = __pc.begin();
>>
>> - auto __finalize = [this, &__spec] {
>> + auto __finalize = [this, &__spec, __type] {
>> _M_spec = __spec;
>> + _M_set_default(__type);
>> };
>>
>> auto __finished = [&] {
>> @@ -2457,19 +2458,23 @@ namespace __format
>> #endif
>>
>> __first = __spec._M_parse_width(__first, __last, __pc);
>> + if (__finished())
>> + return __first;
>>
>> - if (__first != __last)
>> + if (*__first == 'p')
>> {
>> - if (*__first == 'p')
>> - ++__first;
>> + __spec._M_type = _Pres_p;
>> + _M_spec._M_alt = !_M_spec._M_alt;
>> + ++__first;
>> + }
>> #if __glibcxx_format >= 202304L
>> - else if (*__first == 'P')
>> - {
>> - __spec._M_type = __format::_Pres_P;
>> - ++__first;
>> - }
>> -#endif
>> + else if (*__first == 'P')
>> + {
>> + __spec._M_type = _Pres_P;
>> + _M_spec._M_alt = !_M_spec._M_alt;
>> + ++__first;
>> }
>> +#endif
>>
>> if (__finished())
>> return __first;
>> @@ -2536,6 +2541,17 @@ namespace __format
>> }
>>
>> private:
>> + [[__gnu__::__always_inline__]]
>> + constexpr void
>> + _M_set_default(_Pres_type __type)
>> + {
>> + if (_M_spec._M_type == _Pres_none && __type != _Pres_none)
>> + {
>> + _M_spec._M_type = __type;
>> + _M_spec._M_alt = !_M_spec._M_alt;
>> + }
>> + }
>> +
>> __format::_Spec<_CharT> _M_spec{};
>> };
>>
>> @@ -2558,11 +2574,8 @@ namespace __format
>> typename basic_format_context<_Out, _CharT>::iterator
>> format(_CharT __u, basic_format_context<_Out, _CharT>& __fc) const
>> {
>> - if (_M_f._M_spec._M_type == __format::_Pres_none
>> - || _M_f._M_spec._M_type == __format::_Pres_c)
>> + if (_M_f._M_spec._M_type == __format::_Pres_c)
>> return _M_f._M_format_character(__u, __fc);
>> - else if (_M_f._M_spec._M_type == __format::_Pres_esc)
>> - return _M_f._M_format_character_escaped(__u, __fc);
>> else
>> return _M_f.format(static_cast<make_unsigned_t<_CharT>>(__u),
>> __fc);
>> }
>> @@ -2570,7 +2583,7 @@ namespace __format
>> #if __glibcxx_format_ranges // C++ >= 23 && HOSTED
>> constexpr void
>> set_debug_format() noexcept
>> - { _M_f._M_spec._M_type = __format::_Pres_esc; }
>> + { _M_f._M_spec._M_debug = true; }
>> #endif
>>
>> private:
>> @@ -2594,11 +2607,8 @@ namespace __format
>> typename basic_format_context<_Out, wchar_t>::iterator
>> format(char __u, basic_format_context<_Out, wchar_t>& __fc) const
>> {
>> - if (_M_f._M_spec._M_type == __format::_Pres_none
>> - || _M_f._M_spec._M_type == __format::_Pres_c)
>> + if (_M_f._M_spec._M_type == __format::_Pres_c)
>> return _M_f._M_format_character(__u, __fc);
>> - else if (_M_f._M_spec._M_type == __format::_Pres_esc)
>> - return _M_f._M_format_character_escaped(__u, __fc);
>> else
>> return _M_f.format(static_cast<unsigned char>(__u), __fc);
>> }
>> @@ -2606,7 +2616,7 @@ namespace __format
>> #if __glibcxx_format_ranges // C++ >= 23 && HOSTED
>> constexpr void
>> set_debug_format() noexcept
>> - { _M_f._M_spec._M_type = __format::_Pres_esc; }
>> + { _M_f._M_spec._M_debug = true; }
>> #endif
>>
>> private:
>> @@ -3792,7 +3802,7 @@ namespace __format
>> }
>> };
>>
>> - enum _Arg_t : unsigned char {
>> + enum class _Arg_t : unsigned char {
>> _Arg_none, _Arg_bool, _Arg_c, _Arg_i, _Arg_u, _Arg_ll, _Arg_ull,
>> _Arg_flt, _Arg_dbl, _Arg_ldbl, _Arg_str, _Arg_sv, _Arg_ptr,
>> _Arg_handle,
>> _Arg_i128, _Arg_u128,
>> @@ -3806,6 +3816,7 @@ namespace __format
>> #endif
>> _Arg_max_
>> };
>> + using enum _Arg_t;
>>
>> template<typename _Context>
>> struct _Arg_value
>> @@ -4373,7 +4384,7 @@ namespace __format
>> {
>> __UINT64_TYPE__ __packed_types = 0;
>> for (auto __i = __types.rbegin(); __i != __types.rend(); ++__i)
>> - __packed_types = (__packed_types << _Bits) | *__i;
>> + __packed_types = (__packed_types << _Bits) | (unsigned)*__i;
>> return __packed_types;
>> }
>> } // namespace __format
>> @@ -4386,7 +4397,7 @@ namespace __format
>> static constexpr int _S_packed_type_mask = 0b11111;
>> static constexpr int _S_max_packed_args = 12;
>>
>> - static_assert( __format::_Arg_max_ <= (1 << _S_packed_type_bits) );
>> + static_assert( (unsigned)__format::_Arg_max_ <= (1u <<
>> _S_packed_type_bits) );
>>
>> template<typename... _Args>
>> using _Store = __format::_Arg_store<_Context, _Args...>;
>> @@ -5725,7 +5736,7 @@ namespace __format
>> if (*__first == '?')
>> {
>> ++__first;
>> - __spec._M_type = __format::_Pres_esc;
>> + __spec._M_debug = true;
>> if (__finished() || *__first != 's')
>> __throw_format_error("format error: '?' is allowed only in"
>> " combination with 's'");
>> @@ -5736,8 +5747,7 @@ namespace __format
>> ++__first;
>> if constexpr (same_as<_Tp, _CharT>)
>> {
>> - if (__spec._M_type != __format::_Pres_esc)
>> - __spec._M_type = __format::_Pres_str;
>> + __spec._M_type = __format::_Pres_s;
>> if (__finished())
>> return __finalize();
>> __throw_format_error("format error: element format
>> specifier"
>> @@ -5819,8 +5829,7 @@ namespace __format
>> _M_format(_Rg& __rg, basic_format_context<_Out, _CharT>& __fc)
>> const
>> {
>> if constexpr (same_as<_Tp, _CharT>)
>> - if (_M_spec._M_type == __format::_Pres_str
>> - || _M_spec._M_type == __format::_Pres_esc)
>> + if (_M_spec._M_type == __format::_Pres_s)
>> {
>> __format::__formatter_str __fstr(_M_spec);
>> return __fstr._M_format_range(__rg, __fc);
>> --
>> 2.49.0
>>
>>
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