From e14f918e63e3673ba80f8b9e1e6fb5c2ef2958a8 Mon Sep 17 00:00:00 2001
From: Julien Fischer <juliensf@gmail.com>
Date: Sun, 3 Dec 2023 00:19:48 +1100
Subject: [PATCH] Delete MR_HAVE_STDINT_H.

The configure script currently contains a check for the presence of the C99
header stdint.h. This is redundant since (1) *all* C compilers that are
currently capable of compiling Mercury support C99 and (2) most #includes of
stdint.h in the Mercury system are not, and have never been, protected by the
MR_HAVE_STDINT_H anyway.

configure.ac:
runtime/mercury_conf.h.in:
    Do not check for stdint.h.

runtime/mercury_std.h:
    Delete the one remaining use of the MR_HAVE_STDINT_H macro.
---
 configure.ac              | 2 +-
 runtime/mercury_conf.h.in | 4 +---
 runtime/mercury_std.h     | 9 ++-------
 3 files changed, 4 insertions(+), 11 deletions(-)

diff --git a/configure.ac b/configure.ac
index af31e073d..7f0c3b98a 100644
--- a/configure.ac
+++ b/configure.ac
@@ -1484,7 +1484,7 @@ MERCURY_CHECK_FOR_HEADERS( \
         sys/types.h sys/stat.h fcntl.h termios.h sys/ioctl.h \
         sys/resource.h sys/stropts.h windows.h dirent.h getopt.h malloc.h \
         semaphore.h pthread.h time.h spawn.h fenv.h sys/mman.h sys/sem.h \
-        sched.h utmpx.h dispatch/dispatch.h stdint.h sys/select.h )
+        sched.h utmpx.h dispatch/dispatch.h sys/select.h )
 
 if test "$MR_HAVE_UCONTEXT_H" != 1; then
     MERCURY_CHECK_FOR_HEADERS(sys/ucontext.h)
diff --git a/runtime/mercury_conf.h.in b/runtime/mercury_conf.h.in
index 63e43cb36..b847ffce1 100644
--- a/runtime/mercury_conf.h.in
+++ b/runtime/mercury_conf.h.in
@@ -1,7 +1,7 @@
 // vim: ts=4 sw=4 expandtab
 
 // Copyright (C) 1995-2003, 2005-2012 The University of Melbourne.
-// Copyright (C) 2013-2021 The Mercury team.
+// Copyright (C) 2013-2021, 2023 The Mercury team.
 // This file is distributed under the terms specified in COPYING.LIB.
 
 // mercury_conf.h.in defines various configuration parameters.
@@ -150,7 +150,6 @@
 //  MR_HAVE_UTMPX_H         we have <utmpx.h>
 //  MR_HAVE_SYS_RESOURCE_H  we have <sys/resource.h>
 //  MR_HAVE_DISPATCH_DISPATCH_H we have <dispatch/dispatch.h>
-//  MR_HAVE_STDINT_H        we have <stdint.h>
 //  MR_HAVE_SYS_SELECT_H    we have <sys/select.h>
 
 #undef  MR_HAVE_SYS_SIGINFO_H
@@ -184,7 +183,6 @@
 #undef  MR_HAVE_UTMPX_H
 #undef  MR_HAVE_SYS_RESOURCE_H
 #undef  MR_HAVE_DISPATCH_DISPATCH_H
-#undef  MR_HAVE_STDINT_H
 #undef  MR_HAVE_SYS_SELECT_H
 
 // MR_HAVE_POSIX_TIMES is defined if we have the POSIX
diff --git a/runtime/mercury_std.h b/runtime/mercury_std.h
index 3c953549b..7e44c6102 100644
--- a/runtime/mercury_std.h
+++ b/runtime/mercury_std.h
@@ -1,7 +1,7 @@
 // vim: ts=4 sw=4 expandtab ft=c
 
 // Copyright (C) 1993-1995, 1997-2005, 2011-2012 The University of Melbourne.
-// Copyright (C) 2014, 2016-2019, 2021 The Mercury team.
+// Copyright (C) 2014, 2016-2019, 2021-2023 The Mercury team.
 // This file is distributed under the terms specified in COPYING.LIB.
 
 // std.h - "standard" [sic] definitions for C:
@@ -15,12 +15,7 @@
 // even if the system libraries we include below it define any functions.
 
 #include "mercury_regs.h"
-
-#if defined(MR_HAVE_STDINT_H)
-    #include <stdint.h>
-#else
-    #error "Mercury requires a system that provides stdint.h"
-#endif
+#include <stdint.h>
 
 // On Windows we need to define _CRT_RAND_S *before* stdlib.h is included,
 // otherwise the declaration for rand_s() will not be visible.