diff --git a/source/lib-intro.tex b/source/lib-intro.tex
index 4698b64fd6..50b46a505b 100644
--- a/source/lib-intro.tex
+++ b/source/lib-intro.tex
@@ -1455,12 +1455,19 @@
 \pnum
 The named module \tcode{std.compat} exports the same declarations as
 the named module \tcode{std}, and
-additionally exports declarations in the global namespace
+additionally exports
+\begin{itemize}
+\item
+declarations in the global namespace
 corresponding to the declarations in namespace \tcode{std}
 that are provided by
 the \Cpp{} headers for C library facilities~(\tref{headers.cpp.c}),
 except the explicitly excluded declarations
-described in \ref{support.c.headers.other}.
+described in \ref{support.c.headers.other} and
+\item
+declarations provided by
+the headers \libheaderref{stdbit.h} and \libheaderref{stdckdint.h}.
+\end{itemize}
 
 \pnum
 It is unspecified to which module a declaration in the standard library
diff --git a/source/numerics.tex b/source/numerics.tex
index b5c31916ab..1cec18cd4c 100644
--- a/source/numerics.tex
+++ b/source/numerics.tex
@@ -16034,3 +16034,48 @@
                                      A, t, d, B, divides<void>{});
 \end{codeblock}
 \end{itemdescr}
+
+\rSec1[numerics.c]{C compatibility}
+
+\rSec2[stdckdint.h.syn]{Header \tcode{<stdckdint.h>} synopsis}
+
+\begin{codeblock}
+#define @\libglobal{__STDC_VERSION_STDCKDINT_H__}@ 202311L
+
+template<class type1, class type2, class type3>
+  bool ckd_add(type1* result, type2 a, type3 b);
+template<class type1, class type2, class type3>
+  bool ckd_sub(type1* result, type2 a, type3 b);
+template<class type1, class type2, class type3>
+  bool ckd_mul(type1* result, type2 a, type3 b);
+\end{codeblock}
+
+\pnum
+\xref{\IsoCUndated{}:2024, 7.20}   %% TODO: change to \xrefc{7.20}
+
+\rSec2[numerics.c.ckdint]{Checked integer operations}
+
+\indexlibraryglobal{ckd_add}%
+\indexlibraryglobal{ckd_sub}%
+\indexlibraryglobal{ckd_mul}%
+\begin{itemdecl}
+template<class type1, class type2, class type3>
+  bool ckd_add(type1* result, type2 a, type3 b);
+template<class type1, class type2, class type3>
+  bool ckd_sub(type1* result, type2 a, type3 b);
+template<class type1, class type2, class type3>
+  bool ckd_mul(type1* result, type2 a, type3 b);
+\end{itemdecl}
+
+\begin{itemdescr}
+\pnum
+\mandates
+Each of the types \tcode{type1}, \tcode{type2}, and \tcode{type3} is a
+cv-unqualified signed or unsigned integer type.
+
+\pnum
+\remarks
+Each function template has the same semantics as
+the corresponding type-generic macro with the same name
+specified in \IsoCUndated{}:2024, 7.20.
+\end{itemdescr}
diff --git a/source/support.tex b/source/support.tex
index 28c15ac913..18b349bfcc 100644
--- a/source/support.tex
+++ b/source/support.tex
@@ -6217,16 +6217,18 @@
 \libheader{stdalign.h} \\
 \libheaderdef{stdarg.h} \\
 \libheader{stdatomic.h} \\
+\libheader{stdbit.h} \\
 \libheader{stdbool.h} \\
-\libheaderdef{stddef.h} \\
 \columnbreak
+\libheader{stdckdint.h} \\
+\libheaderdef{stddef.h} \\
 \libheaderdef{stdint.h} \\
 \libheaderdef{stdio.h} \\
 \libheaderdef{stdlib.h} \\
 \libheaderdef{string.h} \\
+\columnbreak
 \libheader{tgmath.h} \\
 \libheaderdef{time.h} \\
-\columnbreak
 \libheaderdef{uchar.h} \\
 \libheaderdef{wchar.h} \\
 \libheaderdef{wctype.h} \\
@@ -6330,7 +6332,9 @@
 \libheaderref{iso646.h},
 \libheaderref{stdalign.h},\newline
 \libheaderref{stdatomic.h},
-\libheaderref{stdbool.h}, and
+\libheaderref{stdbit.h},
+\libheaderref{stdbool.h},
+\libheaderref{stdckdint.h}, and\newline
 \libheaderref{tgmath.h},
 each of
 which has a name of the form
diff --git a/source/utilities.tex b/source/utilities.tex
index 889bba8d99..20a19c4069 100644
--- a/source/utilities.tex
+++ b/source/utilities.tex
@@ -15474,3 +15474,131 @@
 Otherwise, \tcode{endian::native} is not equal
 to either \tcode{endian::big} or \tcode{endian::little}.
 \end{itemdescr}
+
+\rSec1[stdbit.h.syn]{Header \tcode{<stdbit.h>} synopsis}
+
+\begin{codeblock}
+#define @\libglobal{__STDC_VERSION_STDBIT_H__}@ 202311L
+
+#define @\libglobal{__STDC_ENDIAN_BIG__}@     @\seebelow@
+#define @\libglobal{__STDC_ENDIAN_LITTLE__}@  @\seebelow@
+#define @\libglobal{__STDC_ENDIAN_NATIVE__}@  @\seebelow@
+
+unsigned int @\libglobal{stdc_leading_zeros_uc}@(unsigned char value);
+unsigned int @\libglobal{stdc_leading_zeros_us}@(unsigned short value);
+unsigned int @\libglobal{stdc_leading_zeros_ui}@(unsigned int value);
+unsigned int @\libglobal{stdc_leading_zeros_ul}@(unsigned long int value);
+unsigned int @\libglobal{stdc_leading_zeros_ull}@(unsigned long long int value);
+template<class T> @\seebelow@ @\libglobal{stdc_leading_zeros}@(T value);
+
+unsigned int @\libglobal{stdc_leading_ones_uc}@(unsigned char value);
+unsigned int @\libglobal{stdc_leading_ones_us}@(unsigned short value);
+unsigned int @\libglobal{stdc_leading_ones_ui}@(unsigned int value);
+unsigned int @\libglobal{stdc_leading_ones_ul}@(unsigned long int value);
+unsigned int @\libglobal{stdc_leading_ones_ull}@(unsigned long long int value);
+template<class T> @\seebelow@ @\libglobal{stdc_leading_ones}@(T value);
+
+unsigned int @\libglobal{stdc_trailing_zeros_uc}@(unsigned char value);
+unsigned int @\libglobal{stdc_trailing_zeros_us}@(unsigned short value);
+unsigned int @\libglobal{stdc_trailing_zeros_ui}@(unsigned int value);
+unsigned int @\libglobal{stdc_trailing_zeros_ul}@(unsigned long int value);
+unsigned int @\libglobal{stdc_trailing_zeros_ull}@(unsigned long long int value);
+template<class T> @\seebelow@ @\libglobal{stdc_trailing_zeros}@(T value);
+
+unsigned int @\libglobal{stdc_trailing_ones_uc}@(unsigned char value);
+unsigned int @\libglobal{stdc_trailing_ones_us}@(unsigned short value);
+unsigned int @\libglobal{stdc_trailing_ones_ui}@(unsigned int value);
+unsigned int @\libglobal{stdc_trailing_ones_ul}@(unsigned long int value);
+unsigned int @\libglobal{stdc_trailing_ones_ull}@(unsigned long long int value);
+template<class T> @\seebelow@ @\libglobal{stdc_trailing_ones}@(T value);
+
+unsigned int @\libglobal{stdc_first_leading_zero_uc}@(unsigned char value);
+unsigned int @\libglobal{stdc_first_leading_zero_us}@(unsigned short value);
+unsigned int @\libglobal{stdc_first_leading_zero_ui}@(unsigned int value);
+unsigned int @\libglobal{stdc_first_leading_zero_ul}@(unsigned long int value);
+unsigned int @\libglobal{stdc_first_leading_zero_ull}@(unsigned long long int value);
+template<class T> @\seebelow@ @\libglobal{stdc_first_leading_zero}@(T value);
+
+unsigned int @\libglobal{stdc_first_leading_one_uc}@(unsigned char value);
+unsigned int @\libglobal{stdc_first_leading_one_us}@(unsigned short value);
+unsigned int @\libglobal{stdc_first_leading_one_ui}@(unsigned int value);
+unsigned int @\libglobal{stdc_first_leading_one_ul}@(unsigned long int value);
+unsigned int @\libglobal{stdc_first_leading_one_ull}@(unsigned long long int value);
+template<class T> @\seebelow@ stdc_first_leading_one(T value);
+
+unsigned int @\libglobal{stdc_first_trailing_zero_uc}@(unsigned char value);
+unsigned int @\libglobal{stdc_first_trailing_zero_us}@(unsigned short value);
+unsigned int @\libglobal{stdc_first_trailing_zero_ui}@(unsigned int value);
+unsigned int @\libglobal{stdc_first_trailing_zero_ul}@(unsigned long int value);
+unsigned int @\libglobal{stdc_first_trailing_zero_ull}@(unsigned long long int value);
+template<class T> @\seebelow@ stdc_first_trailing_zero(T value);
+
+unsigned int @\libglobal{stdc_first_trailing_one_uc}@(unsigned char value);
+unsigned int @\libglobal{stdc_first_trailing_one_us}@(unsigned short value);
+unsigned int @\libglobal{stdc_first_trailing_one_ui}@(unsigned int value);
+unsigned int @\libglobal{stdc_first_trailing_one_ul}@(unsigned long int value);
+unsigned int @\libglobal{stdc_first_trailing_one_ull}@(unsigned long long int value);
+template<class T> @\seebelow@ stdc_first_trailing_one(T value);
+
+unsigned int @\libglobal{stdc_count_zeros_uc}@(unsigned char value);
+unsigned int @\libglobal{stdc_count_zeros_us}@(unsigned short value);
+unsigned int @\libglobal{stdc_count_zeros_ui}@(unsigned int value);
+unsigned int @\libglobal{stdc_count_zeros_ul}@(unsigned long int value);
+unsigned int @\libglobal{stdc_count_zeros_ull}@(unsigned long long int value);
+template<class T> @\seebelow@ @\libglobal{stdc_count_zeros}@(T value);
+
+unsigned int @\libglobal{stdc_count_ones_uc}@(unsigned char value);
+unsigned int @\libglobal{stdc_count_ones_us}@(unsigned short value);
+unsigned int @\libglobal{stdc_count_ones_ui}@(unsigned int value);
+unsigned int @\libglobal{stdc_count_ones_ul}@(unsigned long int value);
+unsigned int @\libglobal{stdc_count_ones_ull}@(unsigned long long int value);
+template<class T> @\seebelow@ stdc_count_ones(T value);
+
+bool @\libglobal{stdc_has_single_bit_uc}@(unsigned char value);
+bool @\libglobal{stdc_has_single_bit_us}@(unsigned short value);
+bool @\libglobal{stdc_has_single_bit_ui}@(unsigned int value);
+bool @\libglobal{stdc_has_single_bit_ul}@(unsigned long int value);
+bool @\libglobal{stdc_has_single_bit_ull}@(unsigned long long int value);
+template<class T> bool @\libglobal{stdc_has_single_bit}@(T value);
+
+unsigned int @\libglobal{stdc_bit_width_uc}@(unsigned char value);
+unsigned int @\libglobal{stdc_bit_width_us}@(unsigned short value);
+unsigned int @\libglobal{stdc_bit_width_ui}@(unsigned int value);
+unsigned int @\libglobal{stdc_bit_width_ul}@(unsigned long int value);
+unsigned int @\libglobal{stdc_bit_width_ull}@(unsigned long long int value);
+template<class T> @\seebelow@ @\libglobal{stdc_bit_width}@(T value);
+
+unsigned char @\libglobal{stdc_bit_floor_uc}@(unsigned char value);
+unsigned short @\libglobal{stdc_bit_floor_us}@(unsigned short value);
+unsigned int @\libglobal{stdc_bit_floor_ui}@(unsigned int value);
+unsigned long int @\libglobal{stdc_bit_floor_ul}@(unsigned long int value);
+unsigned long long int @\libglobal{stdc_bit_floor_ull}@(unsigned long long int value);
+template<class T> T @\libglobal{stdc_bit_floor}@(T value);
+
+unsigned char @\libglobal{stdc_bit_ceil_uc}@(unsigned char value);
+unsigned short @\libglobal{stdc_bit_ceil_us}@(unsigned short value);
+unsigned int @\libglobal{stdc_bit_ceil_ui}@(unsigned int value);
+unsigned long int @\libglobal{stdc_bit_ceil_ul}@(unsigned long int value);
+unsigned long long int @\libglobal{stdc_bit_ceil_ull}@(unsigned long long int value);
+template<class T> T @\libglobal{stdc_bit_ceil}@(T value);
+\end{codeblock}
+
+\pnum
+For a function template whose return type is not specified above,
+the return type is
+an \impldef{return types for \tcode{<stdbit.h>} functions} unsigned integer type
+large enough to represent all possible result values.
+Each function template has the same semantics
+as the corresponding type-generic function with the same name
+specified in \IsoCUndated{}:2024, 7.18.  %% change to \xrefc{7.18}
+
+\pnum
+\mandates
+\tcode{T} is an unsigned integer type.
+
+\pnum
+Otherwise,
+the contents and meaning of the header \libheader{stdbit.h} are the same as
+the C standard library header \tcode{<stdbit.h>}.
+
+\xref{\IsoCUndated{}:2024, 7.18}   %% TODO: change to \xrefc{7.18}