Refer to C23 in place of C2X in glibc

WG14 decided to use the name C23 as the informal name of the next
revision of the C standard (notwithstanding the publication date in
2024).  Update references to C2X in glibc to use the C23 name.

This is intended to update everything *except* where it involves
renaming files (the changes involving renaming tests are intended to
be done separately).  In the case of the _ISOC2X_SOURCE feature test
macro - the only user-visible interface involved - support for that
macro is kept for backwards compatibility, while adding
_ISOC23_SOURCE.

Tested for x86_64.

5 files changed, 42 insertions, 42 deletions

diff --git a/manual/arith.texi b/manual/arith.texi
index 2b99cd8389..0742c08ac4 100644
--- a/manual/arith.texi
+++ b/manual/arith.texi
@@ -1904,7 +1904,7 @@ operation.  These functions, defined by TS 18661-1:2014 and TS
 floating-point number); if @var{x} is not a NaN, they return
 @minus{}1.  They raise no floating-point exceptions even for signaling
 NaNs.  (The return value of @minus{}1 for an argument that is not a
-NaN is specified in C2x; the value was unspecified in TS 18661.)
+NaN is specified in C23; the value was unspecified in TS 18661.)
 @end deftypefun
 
 @deftypefun int setpayload (double *@var{x}, double @var{payload})
@@ -2128,7 +2128,7 @@ are NaN, or either is a signaling NaN, NaN is returned.
 @deftypefunx {long double} fminimuml (long double @var{x}, long double @var{y})
 @deftypefunx _FloatN fminimumfN (_Float@var{N} @var{x}, _Float@var{N} @var{y})
 @deftypefunx _FloatNx fminimumfNx (_Float@var{N}x @var{x}, _Float@var{N}x @var{y})
-@standards{C2X, math.h}
+@standards{C23, math.h}
 @safety{@prelim{}@mtsafe{}@assafe{}@acsafe{}}
 The @code{fminimum} function returns the lesser of the two values @var{x}
 and @var{y}.  Unlike @code{fmin}, if either argument is a NaN, NaN is returned.
@@ -2140,7 +2140,7 @@ Positive zero is treated as greater than negative zero.
 @deftypefunx {long double} fmaximuml (long double @var{x}, long double @var{y})
 @deftypefunx _FloatN fmaximumfN (_Float@var{N} @var{x}, _Float@var{N} @var{y})
 @deftypefunx _FloatNx fmaximumfNx (_Float@var{N}x @var{x}, _Float@var{N}x @var{y})
-@standards{C2X, math.h}
+@standards{C23, math.h}
 @safety{@prelim{}@mtsafe{}@assafe{}@acsafe{}}
 The @code{fmaximum} function returns the greater of the two values @var{x}
 and @var{y}.  Unlike @code{fmax}, if either argument is a NaN, NaN is returned.
@@ -2152,7 +2152,7 @@ Positive zero is treated as greater than negative zero.
 @deftypefunx {long double} fminimum_numl (long double @var{x}, long double @var{y})
 @deftypefunx _FloatN fminimum_numfN (_Float@var{N} @var{x}, _Float@var{N} @var{y})
 @deftypefunx _FloatNx fminimum_numfNx (_Float@var{N}x @var{x}, _Float@var{N}x @var{y})
-@standards{C2X, math.h}
+@standards{C23, math.h}
 @safety{@prelim{}@mtsafe{}@assafe{}@acsafe{}}
 The @code{fminimum_num} function returns the lesser of the two values
 @var{x} and @var{y}.  If one argument is a number and the other is a
@@ -2165,7 +2165,7 @@ treated as greater than negative zero.
 @deftypefunx {long double} fmaximum_numl (long double @var{x}, long double @var{y})
 @deftypefunx _FloatN fmaximum_numfN (_Float@var{N} @var{x}, _Float@var{N} @var{y})
 @deftypefunx _FloatNx fmaximum_numfNx (_Float@var{N}x @var{x}, _Float@var{N}x @var{y})
-@standards{C2X, math.h}
+@standards{C23, math.h}
 @safety{@prelim{}@mtsafe{}@assafe{}@acsafe{}}
 The @code{fmaximum_num} function returns the greater of the two values
 @var{x} and @var{y}.  If one argument is a number and the other is a
@@ -2208,7 +2208,7 @@ as the @code{fmax} functions.
 @deftypefunx {long double} fminimum_magl (long double @var{x}, long double @var{y})
 @deftypefunx _FloatN fminimum_magfN (_Float@var{N} @var{x}, _Float@var{N} @var{y})
 @deftypefunx _FloatNx fminimum_magfNx (_Float@var{N}x @var{x}, _Float@var{N}x @var{y})
-@standards{C2X, math.h}
+@standards{C23, math.h}
 @safety{@prelim{}@mtsafe{}@assafe{}@acsafe{}}
 These functions return whichever of the two values @var{x} and @var{y}
 has the smaller absolute value.  If both have the same absolute value,
@@ -2221,7 +2221,7 @@ functions.
 @deftypefunx {long double} fmaximum_magl (long double @var{x}, long double @var{y})
 @deftypefunx _FloatN fmaximum_magfN (_Float@var{N} @var{x}, _Float@var{N} @var{y})
 @deftypefunx _FloatNx fmaximum_magfNx (_Float@var{N}x @var{x}, _Float@var{N}x @var{y})
-@standards{C2X, math.h}
+@standards{C23, math.h}
 @safety{@prelim{}@mtsafe{}@assafe{}@acsafe{}}
 These functions return whichever of the two values @var{x} and @var{y}
 has the greater absolute value.  If both have the same absolute value,
@@ -2234,7 +2234,7 @@ functions.
 @deftypefunx {long double} fminimum_mag_numl (long double @var{x}, long double @var{y})
 @deftypefunx _FloatN fminimum_mag_numfN (_Float@var{N} @var{x}, _Float@var{N} @var{y})
 @deftypefunx _FloatNx fminimum_mag_numfNx (_Float@var{N}x @var{x}, _Float@var{N}x @var{y})
-@standards{C2X, math.h}
+@standards{C23, math.h}
 @safety{@prelim{}@mtsafe{}@assafe{}@acsafe{}}
 These functions return whichever of the two values @var{x} and @var{y}
 has the smaller absolute value.  If both have the same absolute value,
@@ -2247,7 +2247,7 @@ functions.
 @deftypefunx {long double} fmaximum_mag_numl (long double @var{x}, long double @var{y})
 @deftypefunx _FloatN fmaximum_mag_numfN (_Float@var{N} @var{x}, _Float@var{N} @var{y})
 @deftypefunx _FloatNx fmaximum_mag_numfNx (_Float@var{N}x @var{x}, _Float@var{N}x @var{y})
-@standards{C2X, math.h}
+@standards{C23, math.h}
 @safety{@prelim{}@mtsafe{}@assafe{}@acsafe{}}
 These functions return whichever of the two values @var{x} and @var{y}
 has the greater absolute value.  If both have the same absolute value,
@@ -2663,12 +2663,12 @@ A nonempty sequence of digits in the radix specified by @var{base}.
 If @var{base} is zero, decimal radix is assumed unless the series of
 digits begins with @samp{0} (specifying octal radix), or @samp{0x} or
 @samp{0X} (specifying hexadecimal radix), or @samp{0b} or @samp{0B}
-(specifying binary radix; only supported when C2X features are
+(specifying binary radix; only supported when C23 features are
 enabled); in other words, the same syntax used for integer constants in C.
 
 Otherwise @var{base} must have a value between @code{2} and @code{36}.
 If @var{base} is @code{16}, the digits may optionally be preceded by
-@samp{0x} or @samp{0X}.  If @var{base} is @code{2}, and C2X features
+@samp{0x} or @samp{0X}.  If @var{base} is @code{2}, and C23 features
 are enabled, the digits may optionally be preceded by
 @samp{0b} or @samp{0B}.  If base has no legal value the value returned
 is @code{0l} and the global variable @code{errno} is set to @code{EINVAL}.
diff --git a/manual/creature.texi b/manual/creature.texi
index fa5dd9d6ad..3fc53619ea 100644
--- a/manual/creature.texi
+++ b/manual/creature.texi
@@ -220,11 +220,11 @@ when the compiler uses an earlier language version.
 If this macro is defined, ISO C11 extensions to ISO C99 are included.
 @end defvr
 
-@defvr Macro _ISOC2X_SOURCE
-@standards{C2X, (none)}
-If this macro is defined, ISO C2X extensions to ISO C11 are included.
+@defvr Macro _ISOC23_SOURCE
+@standards{C23, (none)}
+If this macro is defined, ISO C23 extensions to ISO C11 are included.
 Only some features from this draft standard are supported by
-@theglibc{}.
+@theglibc{}.  The older name @code{_ISOC2X_SOURCE} is also supported.
 @end defvr
 
 @defvr Macro __STDC_WANT_LIB_EXT2__
@@ -260,7 +260,7 @@ enabled.  Only some of the features from this TS are supported by
 
 @defvr Macro __STDC_WANT_IEC_60559_EXT__
 @standards{ISO, (none)}
-If you define this macro, ISO C2X features defined in Annex F of that
+If you define this macro, ISO C23 features defined in Annex F of that
 standard are enabled.  This affects declarations of the
 @code{totalorder} functions and functions related to NaN payloads.
 @end defvr
diff --git a/manual/stdbit.texi b/manual/stdbit.texi
index 8688930f12..f74d33903a 100644
--- a/manual/stdbit.texi
+++ b/manual/stdbit.texi
@@ -4,7 +4,7 @@
 
 This chapter contains information about functions and macros for
 determining the endianness of integer types and manipulating the bits
-of unsigned integers.  These functions and macros are from ISO C2X and
+of unsigned integers.  These functions and macros are from ISO C23 and
 are declared in the header file @file{stdbit.h}.
 
 The following macros describe the endianness of integer types.  They
@@ -45,7 +45,7 @@ In GCC 14.1 that includes support for @code{unsigned __int128} and
 @deftypefunx {unsigned int} stdc_leading_zeros_ui (unsigned int @var{x})
 @deftypefunx {unsigned int} stdc_leading_zeros_ul (unsigned long int @var{x})
 @deftypefunx {unsigned int} stdc_leading_zeros_ull (unsigned long long int @var{x})
-@standards{C2X, stdbit.h}
+@standards{C23, stdbit.h}
 @safety{@prelim{}@mtsafe{}@assafe{}@acsafe{}}
 The @code{stdc_leading_zeros} functions count the number of leading
 (most significant) zero bits in @var{x}, starting from the most
@@ -58,7 +58,7 @@ the width of @var{x} in bits.
 @deftypefunx {unsigned int} stdc_leading_ones_ui (unsigned int @var{x})
 @deftypefunx {unsigned int} stdc_leading_ones_ul (unsigned long int @var{x})
 @deftypefunx {unsigned int} stdc_leading_ones_ull (unsigned long long int @var{x})
-@standards{C2X, stdbit.h}
+@standards{C23, stdbit.h}
 @safety{@prelim{}@mtsafe{}@assafe{}@acsafe{}}
 The @code{stdc_leading_ones} functions count the number of leading
 (most significant) one bits in @var{x}, starting from the most
@@ -70,7 +70,7 @@ significant bit of the argument type.
 @deftypefunx {unsigned int} stdc_trailing_zeros_ui (unsigned int @var{x})
 @deftypefunx {unsigned int} stdc_trailing_zeros_ul (unsigned long int @var{x})
 @deftypefunx {unsigned int} stdc_trailing_zeros_ull (unsigned long long int @var{x})
-@standards{C2X, stdbit.h}
+@standards{C23, stdbit.h}
 @safety{@prelim{}@mtsafe{}@assafe{}@acsafe{}}
 The @code{stdc_trailing_zeros} functions count the number of trailing
 (least significant) zero bits in @var{x}, starting from the least
@@ -83,7 +83,7 @@ the width of @var{x} in bits.
 @deftypefunx {unsigned int} stdc_trailing_ones_ui (unsigned int @var{x})
 @deftypefunx {unsigned int} stdc_trailing_ones_ul (unsigned long int @var{x})
 @deftypefunx {unsigned int} stdc_trailing_ones_ull (unsigned long long int @var{x})
-@standards{C2X, stdbit.h}
+@standards{C23, stdbit.h}
 @safety{@prelim{}@mtsafe{}@assafe{}@acsafe{}}
 The @code{stdc_trailing_ones} functions count the number of trailing
 (least significant) one bits in @var{x}, starting from the least
@@ -95,7 +95,7 @@ significant bit of the argument type.
 @deftypefunx {unsigned int} stdc_first_leading_zero_ui (unsigned int @var{x})
 @deftypefunx {unsigned int} stdc_first_leading_zero_ul (unsigned long int @var{x})
 @deftypefunx {unsigned int} stdc_first_leading_zero_ull (unsigned long long int @var{x})
-@standards{C2X, stdbit.h}
+@standards{C23, stdbit.h}
 @safety{@prelim{}@mtsafe{}@assafe{}@acsafe{}}
 The @code{stdc_first_leading_zero} functions return the position of
 the most significant zero bit in @var{x}, counting from the most
@@ -108,7 +108,7 @@ significant bit of @var{x} as 1, or zero if there is no zero bit in
 @deftypefunx {unsigned int} stdc_first_leading_one_ui (unsigned int @var{x})
 @deftypefunx {unsigned int} stdc_first_leading_one_ul (unsigned long int @var{x})
 @deftypefunx {unsigned int} stdc_first_leading_one_ull (unsigned long long int @var{x})
-@standards{C2X, stdbit.h}
+@standards{C23, stdbit.h}
 @safety{@prelim{}@mtsafe{}@assafe{}@acsafe{}}
 The @code{stdc_first_leading_one} functions return the position of the
 most significant one bit in @var{x}, counting from the most
@@ -121,7 +121,7 @@ significant bit of @var{x} as 1, or zero if there is no one bit in
 @deftypefunx {unsigned int} stdc_first_trailing_zero_ui (unsigned int @var{x})
 @deftypefunx {unsigned int} stdc_first_trailing_zero_ul (unsigned long int @var{x})
 @deftypefunx {unsigned int} stdc_first_trailing_zero_ull (unsigned long long int @var{x})
-@standards{C2X, stdbit.h}
+@standards{C23, stdbit.h}
 @safety{@prelim{}@mtsafe{}@assafe{}@acsafe{}}
 The @code{stdc_first_trailing_zero} functions return the position of
 the least significant zero bit in @var{x}, counting from the least
@@ -134,7 +134,7 @@ significant bit of @var{x} as 1, or zero if there is no zero bit in
 @deftypefunx {unsigned int} stdc_first_trailing_one_ui (unsigned int @var{x})
 @deftypefunx {unsigned int} stdc_first_trailing_one_ul (unsigned long int @var{x})
 @deftypefunx {unsigned int} stdc_first_trailing_one_ull (unsigned long long int @var{x})
-@standards{C2X, stdbit.h}
+@standards{C23, stdbit.h}
 @safety{@prelim{}@mtsafe{}@assafe{}@acsafe{}}
 The @code{stdc_first_trailing_one} functions return the position of
 the least significant one bit in @var{x}, counting from the least
@@ -147,7 +147,7 @@ significant bit of @var{x} as 1, or zero if there is no one bit in
 @deftypefunx {unsigned int} stdc_count_zeros_ui (unsigned int @var{x})
 @deftypefunx {unsigned int} stdc_count_zeros_ul (unsigned long int @var{x})
 @deftypefunx {unsigned int} stdc_count_zeros_ull (unsigned long long int @var{x})
-@standards{C2X, stdbit.h}
+@standards{C23, stdbit.h}
 @safety{@prelim{}@mtsafe{}@assafe{}@acsafe{}}
 The @code{stdc_count_zeros} functions count the number of zero bits in
 @var{x}.
@@ -158,7 +158,7 @@ The @code{stdc_count_zeros} functions count the number of zero bits in
 @deftypefunx {unsigned int} stdc_count_ones_ui (unsigned int @var{x})
 @deftypefunx {unsigned int} stdc_count_ones_ul (unsigned long int @var{x})
 @deftypefunx {unsigned int} stdc_count_ones_ull (unsigned long long int @var{x})
-@standards{C2X, stdbit.h}
+@standards{C23, stdbit.h}
 @safety{@prelim{}@mtsafe{}@assafe{}@acsafe{}}
 The @code{stdc_count_ones} functions count the number of one bits in
 @var{x}.
@@ -169,7 +169,7 @@ The @code{stdc_count_ones} functions count the number of one bits in
 @deftypefunx {_Bool} stdc_has_single_bit_ui (unsigned int @var{x})
 @deftypefunx {_Bool} stdc_has_single_bit_ul (unsigned long int @var{x})
 @deftypefunx {_Bool} stdc_has_single_bit_ull (unsigned long long int @var{x})
-@standards{C2X, stdbit.h}
+@standards{C23, stdbit.h}
 @safety{@prelim{}@mtsafe{}@assafe{}@acsafe{}}
 The @code{stdc_has_single_bit} functions return whether @var{x} has
 exactly one bit set to one.
@@ -180,7 +180,7 @@ exactly one bit set to one.
 @deftypefunx {unsigned int} stdc_bit_width_ui (unsigned int @var{x})
 @deftypefunx {unsigned int} stdc_bit_width_ul (unsigned long int @var{x})
 @deftypefunx {unsigned int} stdc_bit_width_ull (unsigned long long int @var{x})
-@standards{C2X, stdbit.h}
+@standards{C23, stdbit.h}
 @safety{@prelim{}@mtsafe{}@assafe{}@acsafe{}}
 The @code{stdc_bit_width} functions return the minimum number of bits
 needed to store @var{x}, not counting leading zero bits.  If @var{x}
@@ -192,7 +192,7 @@ is zero, they return zero.
 @deftypefunx {unsigned int} stdc_bit_floor_ui (unsigned int @var{x})
 @deftypefunx {unsigned long int} stdc_bit_floor_ul (unsigned long int @var{x})
 @deftypefunx {unsigned long long int} stdc_bit_floor_ull (unsigned long long int @var{x})
-@standards{C2X, stdbit.h}
+@standards{C23, stdbit.h}
 @safety{@prelim{}@mtsafe{}@assafe{}@acsafe{}}
 The @code{stdc_bit_floor} functions return the largest integer power
 of two that is less than or equal to @var{x}.  If @var{x} is zero,
@@ -204,7 +204,7 @@ they return zero.
 @deftypefunx {unsigned int} stdc_bit_ceil_ui (unsigned int @var{x})
 @deftypefunx {unsigned long int} stdc_bit_ceil_ul (unsigned long int @var{x})
 @deftypefunx {unsigned long long int} stdc_bit_ceil_ull (unsigned long long int @var{x})
-@standards{C2X, stdbit.h}
+@standards{C23, stdbit.h}
 @safety{@prelim{}@mtsafe{}@assafe{}@acsafe{}}
 The @code{stdc_bit_ceil} functions return the smallest integer power
 of two that is greater than or equal to @var{x}.  If this cannot be
diff --git a/manual/stdio.texi b/manual/stdio.texi
index 002fce7a10..f5e289d58a 100644
--- a/manual/stdio.texi
+++ b/manual/stdio.texi
@@ -1828,8 +1828,8 @@ output, but are different when used with @code{scanf} for input
 @item @samp{%b}, @samp{%B}
 Print an integer as an unsigned binary number.  @samp{%b} uses
 lower-case @samp{b} with the @samp{#} flag and @samp{%B} uses
-upper-case.  @samp{%b} is an ISO C2X feature; @samp{%B} is an
-optional ISO C2X feature.  @xref{Integer Conversions}, for
+upper-case.  @samp{%b} is an ISO C23 feature; @samp{%B} is an
+optional ISO C23 feature.  @xref{Integer Conversions}, for
 details.
 
 @item @samp{%o}
@@ -2036,7 +2036,7 @@ taking signed integers, or @code{uint@var{n}_t} or
 taking unsigned integers.  If the type is narrower than @code{int},
 the promoted argument is converted back to the specified type.
 
-This modifier was introduced in @w{ISO C2X}.
+This modifier was introduced in @w{ISO C23}.
 
 @item wf@var{n}
 Specifies that the argument is a @code{int_fast@var{n}_t} or
@@ -2044,7 +2044,7 @@ Specifies that the argument is a @code{int_fast@var{n}_t} or
 than @code{int}, the promoted argument is converted back to the
 specified type.
 
-This modifier was introduced in @w{ISO C2X}.
+This modifier was introduced in @w{ISO C23}.
 
 @item z
 @itemx Z
@@ -2144,7 +2144,7 @@ specifier is @samp{%a}, @samp{%e}, @samp{%f}, or @samp{%g} and it is
 @w{[@code{-}]@code{INF}} or @code{NAN} respectively if the conversion is
 @samp{%A}, @samp{%E}, @samp{%F} or @samp{%G}.  On some implementations, a NaN
 may result in longer output with information about the payload of the
-NaN; ISO C2X defines a macro @code{_PRINTF_NAN_LEN_MAX} giving the
+NaN; ISO C23 defines a macro @code{_PRINTF_NAN_LEN_MAX} giving the
 maximum length of such output.
 
 The following flags can be used to modify the behavior:
@@ -3547,7 +3547,7 @@ Input Conversions}.
 
 @item @samp{%b}
 Matches an unsigned integer written in binary radix.  This is an ISO
-C2X feature.  @xref{Numeric Input Conversions}.
+C23 feature.  @xref{Numeric Input Conversions}.
 
 @item @samp{%o}
 Matches an unsigned integer written in octal radix.
@@ -3720,13 +3720,13 @@ Specifies that the argument is an @code{int@var{n}_t *} or
 @code{uint@var{n}_t *} or @code{uint_least@var{n}_t *} (which are the
 same type).
 
-This modifier was introduced in @w{ISO C2X}.
+This modifier was introduced in @w{ISO C23}.
 
 @item wf@var{n}
 Specifies that the argument is an @code{int_fast@var{n}_t *} or
 @code{uint_fast@var{n}_t *}.
 
-This modifier was introduced in @w{ISO C2X}.
+This modifier was introduced in @w{ISO C23}.
 
 @item z
 Specifies that the argument is a @code{size_t *}.
diff --git a/manual/time.texi b/manual/time.texi
index 7d9efc7c6f..dd77d3db04 100644
--- a/manual/time.texi
+++ b/manual/time.texi
@@ -1493,7 +1493,7 @@ With @code{%B}, @code{%b}, and @code{%h}: use the grammatical form for
 month names that is appropriate when the month is named by itself,
 rather than the form that is appropriate when the month is used as
 part of a complete date.  The @code{%OB} and @code{%Ob} formats are a
-C2X feature, specified in C2X to use the locale's `alternative' month
+C23 feature, specified in C23 to use the locale's `alternative' month
 name; @theglibc{} extends this specification to say that the form used
 in a complete date is the default and the form naming the month by
 itself is the alternative.
@@ -1516,14 +1516,14 @@ The full weekday name according to the current locale.
 @item %b
 The abbreviated month name according to the current locale, in the
 grammatical form used when the month is part of a complete date.
-As a C2X feature (with a more detailed specification in @theglibc{}),
+As a C23 feature (with a more detailed specification in @theglibc{}),
 the @code{O} modifier can be used (@code{%Ob}) to get the grammatical
 form used when the month is named by itself.
 
 @item %B
 The full month name according to the current locale, in the
 grammatical form used when the month is part of a complete date.
-As a C2X feature (with a more detailed specification in @theglibc{}),
+As a C23 feature (with a more detailed specification in @theglibc{}),
 the @code{O} modifier can be used (@code{%OB}) to get the grammatical
 form used when the month is named by itself.