doc/posix-headers/stdint.texi

@node stdint.h
@section @file{stdint.h}

POSIX specification:@* @url{https://pubs.opengroup.org/onlinepubs/9799919799/basedefs/stdint.h.html}

Gnulib module: stdint-h
@mindex stdint-h

Portability problems fixed by Gnulib:
@itemize
@item
This header file is missing on some platforms:
OpenBSD 3.8, AIX 5.1, HP-UX 11.11, MSVC 9.
@item
This header file is very incomplete on some platforms.
@item
The values of @code{SIG_ATOMIC_MIN} and @code{SIG_ATOMIC_MAX} are incorrect
on some platforms:
FreeBSD 6.2/ia64, FreeBSD 13.0/arm64.
@item
The value of @code{WINT_MAX} is incorrect on some platforms:
mingw.
@item
The values of @code{INT8_MAX}, @code{UINT8_MAX} etc. are not usable in
preprocessor expressions on some platforms:
HP-UX 11.23.
@item
The values of @code{INTPTR_MAX} and @code{UINTPTR_MAX}, although correctly
defined in @code{<stdint.h>}, are replaced by empty values when
@code{<limits.h>} or @code{<inttypes.h>} gets included later on some platforms:
Solaris 9 with GCC 4.5 or newer.
@item
The macros @code{WCHAR_MIN} and @code{WCHAR_MAX} are not defined in
@code{<stdint.h>} (only in @code{<wchar.h>}) on some platforms:
Dragonfly.
@item
On some hosts that predate C++11, when using C++ one must define
@code{__STDC_CONSTANT_MACROS} to make visible the definitions of
constant macros such as @code{INTMAX_C}, and one must define
@code{__STDC_LIMIT_MACROS} to make visible the definitions of limit
macros such as @code{INTMAX_MAX}.
@item
The macro @code{SIZE_MAX} has the wrong type,
albeit with the correct value:
32-bit glibc 2.24 (on s390 architecture), Mac OS X 10.7.
@item
Macros like @code{INTMAX_WIDTH} are not defined on some platforms:
glibc 2.24, NetBSD 10.0, many others.
@end itemize

Portability problems not fixed by Gnulib:
@itemize
@item
@code{@{uint,int@}_fast@{8,16,32,64@}_t} may not correspond to the fastest
types available on the system.
Other @code{<stdint.h>} substitutes may define these types differently,
so public header files should avoid these types.
@item
Macros are used instead of typedefs.
@item
Some C preprocessors mishandle constants that do not fit in @code{long int}.
For example, as of 2007, Sun C mishandled @code{#if LLONG_MIN < 0} on
a platform with 32-bit @code{long int} and 64-bit @code{long long int};
this bug was fixed on or before Oracle Developer Studio 12.6
(Sun C 5.15 SunOS_sparc 2017/05/30).
Some older preprocessors mishandle constants ending in @code{LL}.
To work around these problems, compute the value of expressions like
@code{LONG_MAX < LLONG_MAX} at @code{configure}-time rather than at
@code{#if}-time.
@end itemize

The @code{stdint-h} module uses @code{#include_next}.  If you wish to install
the generated stdint.h file under another name, typically in order to
be able to use some of the types defined by stdint.h in your public
header file, you could use the following Makefile.am-snippet:

@example

BUILT_SOURCES += idn-int.h
DISTCLEANFILES += idn-int.h
nodist_include_HEADERS += idn-int.h

idn-int.h:
	if test -n "$(STDINT_H)"; then \
		sed -e s/include_next/include/ gl/stdint.h > idn-int.h; \
	else \
		echo '#include <stdint.h>' > idn-int.h; \
	fi
@end example