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aclocal.m4
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# generated automatically by aclocal 1.16.5 -*- Autoconf -*-
# Copyright (C) 1996-2021 Free Software Foundation, Inc.
# This file is free software; the Free Software Foundation
# gives unlimited permission to copy and/or distribute it,
# with or without modifications, as long as this notice is preserved.
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY, to the extent permitted by law; without
# even the implied warranty of MERCHANTABILITY or FITNESS FOR A
# PARTICULAR PURPOSE.
m4_ifndef([AC_CONFIG_MACRO_DIRS], [m4_defun([_AM_CONFIG_MACRO_DIRS], [])m4_defun([AC_CONFIG_MACRO_DIRS], [_AM_CONFIG_MACRO_DIRS($@)])])
m4_ifndef([AC_AUTOCONF_VERSION],
[m4_copy([m4_PACKAGE_VERSION], [AC_AUTOCONF_VERSION])])dnl
m4_if(m4_defn([AC_AUTOCONF_VERSION]), [2.71],,
[m4_warning([this file was generated for autoconf 2.71.
You have another version of autoconf. It may work, but is not guaranteed to.
If you have problems, you may need to regenerate the build system entirely.
To do so, use the procedure documented by the package, typically 'autoreconf'.])])
# ============================================================================
# https://www.gnu.org/software/autoconf-archive/ax_append_compile_flags.html
# ============================================================================
#
# SYNOPSIS
#
# AX_APPEND_COMPILE_FLAGS([FLAG1 FLAG2 ...], [FLAGS-VARIABLE], [EXTRA-FLAGS], [INPUT])
#
# DESCRIPTION
#
# For every FLAG1, FLAG2 it is checked whether the compiler works with the
# flag. If it does, the flag is added FLAGS-VARIABLE
#
# If FLAGS-VARIABLE is not specified, the current language's flags (e.g.
# CFLAGS) is used. During the check the flag is always added to the
# current language's flags.
#
# If EXTRA-FLAGS is defined, it is added to the current language's default
# flags (e.g. CFLAGS) when the check is done. The check is thus made with
# the flags: "CFLAGS EXTRA-FLAGS FLAG". This can for example be used to
# force the compiler to issue an error when a bad flag is given.
#
# INPUT gives an alternative input source to AC_COMPILE_IFELSE.
#
# NOTE: This macro depends on the AX_APPEND_FLAG and
# AX_CHECK_COMPILE_FLAG. Please keep this macro in sync with
# AX_APPEND_LINK_FLAGS.
#
# LICENSE
#
# Copyright (c) 2011 Maarten Bosmans <mkbosmans@gmail.com>
#
# Copying and distribution of this file, with or without modification, are
# permitted in any medium without royalty provided the copyright notice
# and this notice are preserved. This file is offered as-is, without any
# warranty.
#serial 7
AC_DEFUN([AX_APPEND_COMPILE_FLAGS],
[AX_REQUIRE_DEFINED([AX_CHECK_COMPILE_FLAG])
AX_REQUIRE_DEFINED([AX_APPEND_FLAG])
for flag in $1; do
AX_CHECK_COMPILE_FLAG([$flag], [AX_APPEND_FLAG([$flag], [$2])], [], [$3], [$4])
done
])dnl AX_APPEND_COMPILE_FLAGS
# ===========================================================================
# https://www.gnu.org/software/autoconf-archive/ax_append_flag.html
# ===========================================================================
#
# SYNOPSIS
#
# AX_APPEND_FLAG(FLAG, [FLAGS-VARIABLE])
#
# DESCRIPTION
#
# FLAG is appended to the FLAGS-VARIABLE shell variable, with a space
# added in between.
#
# If FLAGS-VARIABLE is not specified, the current language's flags (e.g.
# CFLAGS) is used. FLAGS-VARIABLE is not changed if it already contains
# FLAG. If FLAGS-VARIABLE is unset in the shell, it is set to exactly
# FLAG.
#
# NOTE: Implementation based on AX_CFLAGS_GCC_OPTION.
#
# LICENSE
#
# Copyright (c) 2008 Guido U. Draheim <guidod@gmx.de>
# Copyright (c) 2011 Maarten Bosmans <mkbosmans@gmail.com>
#
# Copying and distribution of this file, with or without modification, are
# permitted in any medium without royalty provided the copyright notice
# and this notice are preserved. This file is offered as-is, without any
# warranty.
#serial 8
AC_DEFUN([AX_APPEND_FLAG],
[dnl
AC_PREREQ(2.64)dnl for _AC_LANG_PREFIX and AS_VAR_SET_IF
AS_VAR_PUSHDEF([FLAGS], [m4_default($2,_AC_LANG_PREFIX[FLAGS])])
AS_VAR_SET_IF(FLAGS,[
AS_CASE([" AS_VAR_GET(FLAGS) "],
[*" $1 "*], [AC_RUN_LOG([: FLAGS already contains $1])],
[
AS_VAR_APPEND(FLAGS,[" $1"])
AC_RUN_LOG([: FLAGS="$FLAGS"])
])
],
[
AS_VAR_SET(FLAGS,[$1])
AC_RUN_LOG([: FLAGS="$FLAGS"])
])
AS_VAR_POPDEF([FLAGS])dnl
])dnl AX_APPEND_FLAG
# ===========================================================================
# https://www.gnu.org/software/autoconf-archive/ax_append_link_flags.html
# ===========================================================================
#
# SYNOPSIS
#
# AX_APPEND_LINK_FLAGS([FLAG1 FLAG2 ...], [FLAGS-VARIABLE], [EXTRA-FLAGS], [INPUT])
#
# DESCRIPTION
#
# For every FLAG1, FLAG2 it is checked whether the linker works with the
# flag. If it does, the flag is added FLAGS-VARIABLE
#
# If FLAGS-VARIABLE is not specified, the linker's flags (LDFLAGS) is
# used. During the check the flag is always added to the linker's flags.
#
# If EXTRA-FLAGS is defined, it is added to the linker's default flags
# when the check is done. The check is thus made with the flags: "LDFLAGS
# EXTRA-FLAGS FLAG". This can for example be used to force the linker to
# issue an error when a bad flag is given.
#
# INPUT gives an alternative input source to AC_COMPILE_IFELSE.
#
# NOTE: This macro depends on the AX_APPEND_FLAG and AX_CHECK_LINK_FLAG.
# Please keep this macro in sync with AX_APPEND_COMPILE_FLAGS.
#
# LICENSE
#
# Copyright (c) 2011 Maarten Bosmans <mkbosmans@gmail.com>
#
# Copying and distribution of this file, with or without modification, are
# permitted in any medium without royalty provided the copyright notice
# and this notice are preserved. This file is offered as-is, without any
# warranty.
#serial 7
AC_DEFUN([AX_APPEND_LINK_FLAGS],
[AX_REQUIRE_DEFINED([AX_CHECK_LINK_FLAG])
AX_REQUIRE_DEFINED([AX_APPEND_FLAG])
for flag in $1; do
AX_CHECK_LINK_FLAG([$flag], [AX_APPEND_FLAG([$flag], [m4_default([$2], [LDFLAGS])])], [], [$3], [$4])
done
])dnl AX_APPEND_LINK_FLAGS
# ===========================================================================
# https://www.gnu.org/software/autoconf-archive/ax_check_compile_flag.html
# ===========================================================================
#
# SYNOPSIS
#
# AX_CHECK_COMPILE_FLAG(FLAG, [ACTION-SUCCESS], [ACTION-FAILURE], [EXTRA-FLAGS], [INPUT])
#
# DESCRIPTION
#
# Check whether the given FLAG works with the current language's compiler
# or gives an error. (Warnings, however, are ignored)
#
# ACTION-SUCCESS/ACTION-FAILURE are shell commands to execute on
# success/failure.
#
# If EXTRA-FLAGS is defined, it is added to the current language's default
# flags (e.g. CFLAGS) when the check is done. The check is thus made with
# the flags: "CFLAGS EXTRA-FLAGS FLAG". This can for example be used to
# force the compiler to issue an error when a bad flag is given.
#
# INPUT gives an alternative input source to AC_COMPILE_IFELSE.
#
# NOTE: Implementation based on AX_CFLAGS_GCC_OPTION. Please keep this
# macro in sync with AX_CHECK_{PREPROC,LINK}_FLAG.
#
# LICENSE
#
# Copyright (c) 2008 Guido U. Draheim <guidod@gmx.de>
# Copyright (c) 2011 Maarten Bosmans <mkbosmans@gmail.com>
#
# Copying and distribution of this file, with or without modification, are
# permitted in any medium without royalty provided the copyright notice
# and this notice are preserved. This file is offered as-is, without any
# warranty.
#serial 6
AC_DEFUN([AX_CHECK_COMPILE_FLAG],
[AC_PREREQ(2.64)dnl for _AC_LANG_PREFIX and AS_VAR_IF
AS_VAR_PUSHDEF([CACHEVAR],[ax_cv_check_[]_AC_LANG_ABBREV[]flags_$4_$1])dnl
AC_CACHE_CHECK([whether _AC_LANG compiler accepts $1], CACHEVAR, [
ax_check_save_flags=$[]_AC_LANG_PREFIX[]FLAGS
_AC_LANG_PREFIX[]FLAGS="$[]_AC_LANG_PREFIX[]FLAGS $4 $1"
AC_COMPILE_IFELSE([m4_default([$5],[AC_LANG_PROGRAM()])],
[AS_VAR_SET(CACHEVAR,[yes])],
[AS_VAR_SET(CACHEVAR,[no])])
_AC_LANG_PREFIX[]FLAGS=$ax_check_save_flags])
AS_VAR_IF(CACHEVAR,yes,
[m4_default([$2], :)],
[m4_default([$3], :)])
AS_VAR_POPDEF([CACHEVAR])dnl
])dnl AX_CHECK_COMPILE_FLAGS
# ===========================================================================
# https://www.gnu.org/software/autoconf-archive/ax_check_link_flag.html
# ===========================================================================
#
# SYNOPSIS
#
# AX_CHECK_LINK_FLAG(FLAG, [ACTION-SUCCESS], [ACTION-FAILURE], [EXTRA-FLAGS], [INPUT])
#
# DESCRIPTION
#
# Check whether the given FLAG works with the linker or gives an error.
# (Warnings, however, are ignored)
#
# ACTION-SUCCESS/ACTION-FAILURE are shell commands to execute on
# success/failure.
#
# If EXTRA-FLAGS is defined, it is added to the linker's default flags
# when the check is done. The check is thus made with the flags: "LDFLAGS
# EXTRA-FLAGS FLAG". This can for example be used to force the linker to
# issue an error when a bad flag is given.
#
# INPUT gives an alternative input source to AC_LINK_IFELSE.
#
# NOTE: Implementation based on AX_CFLAGS_GCC_OPTION. Please keep this
# macro in sync with AX_CHECK_{PREPROC,COMPILE}_FLAG.
#
# LICENSE
#
# Copyright (c) 2008 Guido U. Draheim <guidod@gmx.de>
# Copyright (c) 2011 Maarten Bosmans <mkbosmans@gmail.com>
#
# Copying and distribution of this file, with or without modification, are
# permitted in any medium without royalty provided the copyright notice
# and this notice are preserved. This file is offered as-is, without any
# warranty.
#serial 6
AC_DEFUN([AX_CHECK_LINK_FLAG],
[AC_PREREQ(2.64)dnl for _AC_LANG_PREFIX and AS_VAR_IF
AS_VAR_PUSHDEF([CACHEVAR],[ax_cv_check_ldflags_$4_$1])dnl
AC_CACHE_CHECK([whether the linker accepts $1], CACHEVAR, [
ax_check_save_flags=$LDFLAGS
LDFLAGS="$LDFLAGS $4 $1"
AC_LINK_IFELSE([m4_default([$5],[AC_LANG_PROGRAM()])],
[AS_VAR_SET(CACHEVAR,[yes])],
[AS_VAR_SET(CACHEVAR,[no])])
LDFLAGS=$ax_check_save_flags])
AS_VAR_IF(CACHEVAR,yes,
[m4_default([$2], :)],
[m4_default([$3], :)])
AS_VAR_POPDEF([CACHEVAR])dnl
])dnl AX_CHECK_LINK_FLAGS
# ===========================================================================
# https://www.gnu.org/software/autoconf-archive/ax_pthread.html
# ===========================================================================
#
# SYNOPSIS
#
# AX_PTHREAD([ACTION-IF-FOUND[, ACTION-IF-NOT-FOUND]])
#
# DESCRIPTION
#
# This macro figures out how to build C programs using POSIX threads. It
# sets the PTHREAD_LIBS output variable to the threads library and linker
# flags, and the PTHREAD_CFLAGS output variable to any special C compiler
# flags that are needed. (The user can also force certain compiler
# flags/libs to be tested by setting these environment variables.)
#
# Also sets PTHREAD_CC and PTHREAD_CXX to any special C compiler that is
# needed for multi-threaded programs (defaults to the value of CC
# respectively CXX otherwise). (This is necessary on e.g. AIX to use the
# special cc_r/CC_r compiler alias.)
#
# NOTE: You are assumed to not only compile your program with these flags,
# but also to link with them as well. For example, you might link with
# $PTHREAD_CC $CFLAGS $PTHREAD_CFLAGS $LDFLAGS ... $PTHREAD_LIBS $LIBS
# $PTHREAD_CXX $CXXFLAGS $PTHREAD_CFLAGS $LDFLAGS ... $PTHREAD_LIBS $LIBS
#
# If you are only building threaded programs, you may wish to use these
# variables in your default LIBS, CFLAGS, and CC:
#
# LIBS="$PTHREAD_LIBS $LIBS"
# CFLAGS="$CFLAGS $PTHREAD_CFLAGS"
# CXXFLAGS="$CXXFLAGS $PTHREAD_CFLAGS"
# CC="$PTHREAD_CC"
# CXX="$PTHREAD_CXX"
#
# In addition, if the PTHREAD_CREATE_JOINABLE thread-attribute constant
# has a nonstandard name, this macro defines PTHREAD_CREATE_JOINABLE to
# that name (e.g. PTHREAD_CREATE_UNDETACHED on AIX).
#
# Also HAVE_PTHREAD_PRIO_INHERIT is defined if pthread is found and the
# PTHREAD_PRIO_INHERIT symbol is defined when compiling with
# PTHREAD_CFLAGS.
#
# ACTION-IF-FOUND is a list of shell commands to run if a threads library
# is found, and ACTION-IF-NOT-FOUND is a list of commands to run it if it
# is not found. If ACTION-IF-FOUND is not specified, the default action
# will define HAVE_PTHREAD.
#
# Please let the authors know if this macro fails on any platform, or if
# you have any other suggestions or comments. This macro was based on work
# by SGJ on autoconf scripts for FFTW (http://www.fftw.org/) (with help
# from M. Frigo), as well as ac_pthread and hb_pthread macros posted by
# Alejandro Forero Cuervo to the autoconf macro repository. We are also
# grateful for the helpful feedback of numerous users.
#
# Updated for Autoconf 2.68 by Daniel Richard G.
#
# LICENSE
#
# Copyright (c) 2008 Steven G. Johnson <stevenj@alum.mit.edu>
# Copyright (c) 2011 Daniel Richard G. <skunk@iSKUNK.ORG>
# Copyright (c) 2019 Marc Stevens <marc.stevens@cwi.nl>
#
# This program is free software: you can redistribute it and/or modify it
# under the terms of the GNU General Public License as published by the
# Free Software Foundation, either version 3 of the License, or (at your
# option) any later version.
#
# This program is distributed in the hope that it will be useful, but
# WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General
# Public License for more details.
#
# You should have received a copy of the GNU General Public License along
# with this program. If not, see <https://www.gnu.org/licenses/>.
#
# As a special exception, the respective Autoconf Macro's copyright owner
# gives unlimited permission to copy, distribute and modify the configure
# scripts that are the output of Autoconf when processing the Macro. You
# need not follow the terms of the GNU General Public License when using
# or distributing such scripts, even though portions of the text of the
# Macro appear in them. The GNU General Public License (GPL) does govern
# all other use of the material that constitutes the Autoconf Macro.
#
# This special exception to the GPL applies to versions of the Autoconf
# Macro released by the Autoconf Archive. When you make and distribute a
# modified version of the Autoconf Macro, you may extend this special
# exception to the GPL to apply to your modified version as well.
#serial 31
AU_ALIAS([ACX_PTHREAD], [AX_PTHREAD])
AC_DEFUN([AX_PTHREAD], [
AC_REQUIRE([AC_CANONICAL_HOST])
AC_REQUIRE([AC_PROG_CC])
AC_REQUIRE([AC_PROG_SED])
AC_LANG_PUSH([C])
ax_pthread_ok=no
# We used to check for pthread.h first, but this fails if pthread.h
# requires special compiler flags (e.g. on Tru64 or Sequent).
# It gets checked for in the link test anyway.
# First of all, check if the user has set any of the PTHREAD_LIBS,
# etcetera environment variables, and if threads linking works using
# them:
if test "x$PTHREAD_CFLAGS$PTHREAD_LIBS" != "x"; then
ax_pthread_save_CC="$CC"
ax_pthread_save_CFLAGS="$CFLAGS"
ax_pthread_save_LIBS="$LIBS"
AS_IF([test "x$PTHREAD_CC" != "x"], [CC="$PTHREAD_CC"])
AS_IF([test "x$PTHREAD_CXX" != "x"], [CXX="$PTHREAD_CXX"])
CFLAGS="$CFLAGS $PTHREAD_CFLAGS"
LIBS="$PTHREAD_LIBS $LIBS"
AC_MSG_CHECKING([for pthread_join using $CC $PTHREAD_CFLAGS $PTHREAD_LIBS])
AC_LINK_IFELSE([AC_LANG_CALL([], [pthread_join])], [ax_pthread_ok=yes])
AC_MSG_RESULT([$ax_pthread_ok])
if test "x$ax_pthread_ok" = "xno"; then
PTHREAD_LIBS=""
PTHREAD_CFLAGS=""
fi
CC="$ax_pthread_save_CC"
CFLAGS="$ax_pthread_save_CFLAGS"
LIBS="$ax_pthread_save_LIBS"
fi
# We must check for the threads library under a number of different
# names; the ordering is very important because some systems
# (e.g. DEC) have both -lpthread and -lpthreads, where one of the
# libraries is broken (non-POSIX).
# Create a list of thread flags to try. Items with a "," contain both
# C compiler flags (before ",") and linker flags (after ","). Other items
# starting with a "-" are C compiler flags, and remaining items are
# library names, except for "none" which indicates that we try without
# any flags at all, and "pthread-config" which is a program returning
# the flags for the Pth emulation library.
ax_pthread_flags="pthreads none -Kthread -pthread -pthreads -mthreads pthread --thread-safe -mt pthread-config"
# The ordering *is* (sometimes) important. Some notes on the
# individual items follow:
# pthreads: AIX (must check this before -lpthread)
# none: in case threads are in libc; should be tried before -Kthread and
# other compiler flags to prevent continual compiler warnings
# -Kthread: Sequent (threads in libc, but -Kthread needed for pthread.h)
# -pthread: Linux/gcc (kernel threads), BSD/gcc (userland threads), Tru64
# (Note: HP C rejects this with "bad form for `-t' option")
# -pthreads: Solaris/gcc (Note: HP C also rejects)
# -mt: Sun Workshop C (may only link SunOS threads [-lthread], but it
# doesn't hurt to check since this sometimes defines pthreads and
# -D_REENTRANT too), HP C (must be checked before -lpthread, which
# is present but should not be used directly; and before -mthreads,
# because the compiler interprets this as "-mt" + "-hreads")
# -mthreads: Mingw32/gcc, Lynx/gcc
# pthread: Linux, etcetera
# --thread-safe: KAI C++
# pthread-config: use pthread-config program (for GNU Pth library)
case $host_os in
freebsd*)
# -kthread: FreeBSD kernel threads (preferred to -pthread since SMP-able)
# lthread: LinuxThreads port on FreeBSD (also preferred to -pthread)
ax_pthread_flags="-kthread lthread $ax_pthread_flags"
;;
hpux*)
# From the cc(1) man page: "[-mt] Sets various -D flags to enable
# multi-threading and also sets -lpthread."
ax_pthread_flags="-mt -pthread pthread $ax_pthread_flags"
;;
openedition*)
# IBM z/OS requires a feature-test macro to be defined in order to
# enable POSIX threads at all, so give the user a hint if this is
# not set. (We don't define these ourselves, as they can affect
# other portions of the system API in unpredictable ways.)
AC_EGREP_CPP([AX_PTHREAD_ZOS_MISSING],
[
# if !defined(_OPEN_THREADS) && !defined(_UNIX03_THREADS)
AX_PTHREAD_ZOS_MISSING
# endif
],
[AC_MSG_WARN([IBM z/OS requires -D_OPEN_THREADS or -D_UNIX03_THREADS to enable pthreads support.])])
;;
solaris*)
# On Solaris (at least, for some versions), libc contains stubbed
# (non-functional) versions of the pthreads routines, so link-based
# tests will erroneously succeed. (N.B.: The stubs are missing
# pthread_cleanup_push, or rather a function called by this macro,
# so we could check for that, but who knows whether they'll stub
# that too in a future libc.) So we'll check first for the
# standard Solaris way of linking pthreads (-mt -lpthread).
ax_pthread_flags="-mt,-lpthread pthread $ax_pthread_flags"
;;
esac
# Are we compiling with Clang?
AC_CACHE_CHECK([whether $CC is Clang],
[ax_cv_PTHREAD_CLANG],
[ax_cv_PTHREAD_CLANG=no
# Note that Autoconf sets GCC=yes for Clang as well as GCC
if test "x$GCC" = "xyes"; then
AC_EGREP_CPP([AX_PTHREAD_CC_IS_CLANG],
[/* Note: Clang 2.7 lacks __clang_[a-z]+__ */
# if defined(__clang__) && defined(__llvm__)
AX_PTHREAD_CC_IS_CLANG
# endif
],
[ax_cv_PTHREAD_CLANG=yes])
fi
])
ax_pthread_clang="$ax_cv_PTHREAD_CLANG"
# GCC generally uses -pthread, or -pthreads on some platforms (e.g. SPARC)
# Note that for GCC and Clang -pthread generally implies -lpthread,
# except when -nostdlib is passed.
# This is problematic using libtool to build C++ shared libraries with pthread:
# [1] https://gcc.gnu.org/bugzilla/show_bug.cgi?id=25460
# [2] https://bugzilla.redhat.com/show_bug.cgi?id=661333
# [3] https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=468555
# To solve this, first try -pthread together with -lpthread for GCC
AS_IF([test "x$GCC" = "xyes"],
[ax_pthread_flags="-pthread,-lpthread -pthread -pthreads $ax_pthread_flags"])
# Clang takes -pthread (never supported any other flag), but we'll try with -lpthread first
AS_IF([test "x$ax_pthread_clang" = "xyes"],
[ax_pthread_flags="-pthread,-lpthread -pthread"])
# The presence of a feature test macro requesting re-entrant function
# definitions is, on some systems, a strong hint that pthreads support is
# correctly enabled
case $host_os in
darwin* | hpux* | linux* | osf* | solaris*)
ax_pthread_check_macro="_REENTRANT"
;;
aix*)
ax_pthread_check_macro="_THREAD_SAFE"
;;
*)
ax_pthread_check_macro="--"
;;
esac
AS_IF([test "x$ax_pthread_check_macro" = "x--"],
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for ax_pthread_try_flag in $ax_pthread_flags; do
case $ax_pthread_try_flag in
none)
AC_MSG_CHECKING([whether pthreads work without any flags])
;;
*,*)
PTHREAD_CFLAGS=`echo $ax_pthread_try_flag | sed "s/^\(.*\),\(.*\)$/\1/"`
PTHREAD_LIBS=`echo $ax_pthread_try_flag | sed "s/^\(.*\),\(.*\)$/\2/"`
AC_MSG_CHECKING([whether pthreads work with "$PTHREAD_CFLAGS" and "$PTHREAD_LIBS"])
;;
-*)
AC_MSG_CHECKING([whether pthreads work with $ax_pthread_try_flag])
PTHREAD_CFLAGS="$ax_pthread_try_flag"
;;
pthread-config)
AC_CHECK_PROG([ax_pthread_config], [pthread-config], [yes], [no])
AS_IF([test "x$ax_pthread_config" = "xno"], [continue])
PTHREAD_CFLAGS="`pthread-config --cflags`"
PTHREAD_LIBS="`pthread-config --ldflags` `pthread-config --libs`"
;;
*)
AC_MSG_CHECKING([for the pthreads library -l$ax_pthread_try_flag])
PTHREAD_LIBS="-l$ax_pthread_try_flag"
;;
esac
ax_pthread_save_CFLAGS="$CFLAGS"
ax_pthread_save_LIBS="$LIBS"
CFLAGS="$CFLAGS $PTHREAD_CFLAGS"
LIBS="$PTHREAD_LIBS $LIBS"
# Check for various functions. We must include pthread.h,
# since some functions may be macros. (On the Sequent, we
# need a special flag -Kthread to make this header compile.)
# We check for pthread_join because it is in -lpthread on IRIX
# while pthread_create is in libc. We check for pthread_attr_init
# due to DEC craziness with -lpthreads. We check for
# pthread_cleanup_push because it is one of the few pthread
# functions on Solaris that doesn't have a non-functional libc stub.
# We try pthread_create on general principles.
AC_LINK_IFELSE([AC_LANG_PROGRAM([#include <pthread.h>
# if $ax_pthread_check_cond
# error "$ax_pthread_check_macro must be defined"
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static void routine(void *a)
{
/* To avoid any unused-parameter or
unused-but-set-parameter warning. */
some_global = a;
}
static void *start_routine(void *a) { return a; }],
[pthread_t th; pthread_attr_t attr;
pthread_create(&th, 0, start_routine, 0);
pthread_join(th, 0);
pthread_attr_init(&attr);
pthread_cleanup_push(routine, 0);
pthread_cleanup_pop(0) /* ; */])],
[ax_pthread_ok=yes],
[])
CFLAGS="$ax_pthread_save_CFLAGS"
LIBS="$ax_pthread_save_LIBS"
AC_MSG_RESULT([$ax_pthread_ok])
AS_IF([test "x$ax_pthread_ok" = "xyes"], [break])
PTHREAD_LIBS=""
PTHREAD_CFLAGS=""
done
fi
# Clang needs special handling, because older versions handle the -pthread
# option in a rather... idiosyncratic way
if test "x$ax_pthread_clang" = "xyes"; then
# Clang takes -pthread; it has never supported any other flag
# (Note 1: This will need to be revisited if a system that Clang
# supports has POSIX threads in a separate library. This tends not
# to be the way of modern systems, but it's conceivable.)
# (Note 2: On some systems, notably Darwin, -pthread is not needed
# to get POSIX threads support; the API is always present and
# active. We could reasonably leave PTHREAD_CFLAGS empty. But
# -pthread does define _REENTRANT, and while the Darwin headers
# ignore this macro, third-party headers might not.)
# However, older versions of Clang make a point of warning the user
# that, in an invocation where only linking and no compilation is
# taking place, the -pthread option has no effect ("argument unused
# during compilation"). They expect -pthread to be passed in only
# when source code is being compiled.
#
# Problem is, this is at odds with the way Automake and most other
# C build frameworks function, which is that the same flags used in
# compilation (CFLAGS) are also used in linking. Many systems
# supported by AX_PTHREAD require exactly this for POSIX threads
# support, and in fact it is often not straightforward to specify a
# flag that is used only in the compilation phase and not in
# linking. Such a scenario is extremely rare in practice.
#
# Even though use of the -pthread flag in linking would only print
# a warning, this can be a nuisance for well-run software projects
# that build with -Werror. So if the active version of Clang has
# this misfeature, we search for an option to squash it.
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[ax_cv_PTHREAD_CLANG_NO_WARN_FLAG],
[ax_cv_PTHREAD_CLANG_NO_WARN_FLAG=unknown
# Create an alternate version of $ac_link that compiles and
# links in two steps (.c -> .o, .o -> exe) instead of one
# (.c -> exe), because the warning occurs only in the second
# step
ax_pthread_save_ac_link="$ac_link"
ax_pthread_sed='s/conftest\.\$ac_ext/conftest.$ac_objext/g'
ax_pthread_link_step=`AS_ECHO(["$ac_link"]) | sed "$ax_pthread_sed"`
ax_pthread_2step_ac_link="($ac_compile) && (echo ==== >&5) && ($ax_pthread_link_step)"
ax_pthread_save_CFLAGS="$CFLAGS"
for ax_pthread_try in '' -Qunused-arguments -Wno-unused-command-line-argument unknown; do
AS_IF([test "x$ax_pthread_try" = "xunknown"], [break])
CFLAGS="-Werror -Wunknown-warning-option $ax_pthread_try -pthread $ax_pthread_save_CFLAGS"
ac_link="$ax_pthread_save_ac_link"
AC_LINK_IFELSE([AC_LANG_SOURCE([[int main(void){return 0;}]])],
[ac_link="$ax_pthread_2step_ac_link"
AC_LINK_IFELSE([AC_LANG_SOURCE([[int main(void){return 0;}]])],
[break])
])
done
ac_link="$ax_pthread_save_ac_link"
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ax_cv_PTHREAD_CLANG_NO_WARN_FLAG="$ax_pthread_try"
])
case "$ax_cv_PTHREAD_CLANG_NO_WARN_FLAG" in
no | unknown) ;;
*) PTHREAD_CFLAGS="$ax_cv_PTHREAD_CLANG_NO_WARN_FLAG $PTHREAD_CFLAGS" ;;
esac
fi # $ax_pthread_clang = yes
# Various other checks:
if test "x$ax_pthread_ok" = "xyes"; then
ax_pthread_save_CFLAGS="$CFLAGS"
ax_pthread_save_LIBS="$LIBS"
CFLAGS="$CFLAGS $PTHREAD_CFLAGS"
LIBS="$PTHREAD_LIBS $LIBS"
# Detect AIX lossage: JOINABLE attribute is called UNDETACHED.
AC_CACHE_CHECK([for joinable pthread attribute],
[ax_cv_PTHREAD_JOINABLE_ATTR],
[ax_cv_PTHREAD_JOINABLE_ATTR=unknown
for ax_pthread_attr in PTHREAD_CREATE_JOINABLE PTHREAD_CREATE_UNDETACHED; do
AC_LINK_IFELSE([AC_LANG_PROGRAM([#include <pthread.h>],
[int attr = $ax_pthread_attr; return attr /* ; */])],
[ax_cv_PTHREAD_JOINABLE_ATTR=$ax_pthread_attr; break],
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done
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AS_IF([test "x$ax_cv_PTHREAD_JOINABLE_ATTR" != "xunknown" && \
test "x$ax_cv_PTHREAD_JOINABLE_ATTR" != "xPTHREAD_CREATE_JOINABLE" && \
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[AC_DEFINE_UNQUOTED([PTHREAD_CREATE_JOINABLE],
[$ax_cv_PTHREAD_JOINABLE_ATTR],
[Define to necessary symbol if this constant
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ax_pthread_joinable_attr_defined=yes
])
AC_CACHE_CHECK([whether more special flags are required for pthreads],
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[ax_cv_PTHREAD_SPECIAL_FLAGS=no
case $host_os in
solaris*)
ax_cv_PTHREAD_SPECIAL_FLAGS="-D_POSIX_PTHREAD_SEMANTICS"
;;
esac
])
AS_IF([test "x$ax_cv_PTHREAD_SPECIAL_FLAGS" != "xno" && \
test "x$ax_pthread_special_flags_added" != "xyes"],
[PTHREAD_CFLAGS="$ax_cv_PTHREAD_SPECIAL_FLAGS $PTHREAD_CFLAGS"
ax_pthread_special_flags_added=yes])
AC_CACHE_CHECK([for PTHREAD_PRIO_INHERIT],
[ax_cv_PTHREAD_PRIO_INHERIT],
[AC_LINK_IFELSE([AC_LANG_PROGRAM([[#include <pthread.h>]],
[[int i = PTHREAD_PRIO_INHERIT;
return i;]])],
[ax_cv_PTHREAD_PRIO_INHERIT=yes],
[ax_cv_PTHREAD_PRIO_INHERIT=no])
])
AS_IF([test "x$ax_cv_PTHREAD_PRIO_INHERIT" = "xyes" && \
test "x$ax_pthread_prio_inherit_defined" != "xyes"],
[AC_DEFINE([HAVE_PTHREAD_PRIO_INHERIT], [1], [Have PTHREAD_PRIO_INHERIT.])
ax_pthread_prio_inherit_defined=yes
])
CFLAGS="$ax_pthread_save_CFLAGS"
LIBS="$ax_pthread_save_LIBS"
# More AIX lossage: compile with *_r variant
if test "x$GCC" != "xyes"; then
case $host_os in
aix*)
AS_CASE(["x/$CC"],
[x*/c89|x*/c89_128|x*/c99|x*/c99_128|x*/cc|x*/cc128|x*/xlc|x*/xlc_v6|x*/xlc128|x*/xlc128_v6],
[#handle absolute path differently from PATH based program lookup
AS_CASE(["x$CC"],
[x/*],
[
AS_IF([AS_EXECUTABLE_P([${CC}_r])],[PTHREAD_CC="${CC}_r"])
AS_IF([test "x${CXX}" != "x"], [AS_IF([AS_EXECUTABLE_P([${CXX}_r])],[PTHREAD_CXX="${CXX}_r"])])
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[
AC_CHECK_PROGS([PTHREAD_CC],[${CC}_r],[$CC])
AS_IF([test "x${CXX}" != "x"], [AC_CHECK_PROGS([PTHREAD_CXX],[${CXX}_r],[$CXX])])
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])
;;
esac
fi
fi
test -n "$PTHREAD_CC" || PTHREAD_CC="$CC"
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AC_SUBST([PTHREAD_LIBS])
AC_SUBST([PTHREAD_CFLAGS])
AC_SUBST([PTHREAD_CC])
AC_SUBST([PTHREAD_CXX])
# Finally, execute ACTION-IF-FOUND/ACTION-IF-NOT-FOUND:
if test "x$ax_pthread_ok" = "xyes"; then
ifelse([$1],,[AC_DEFINE([HAVE_PTHREAD],[1],[Define if you have POSIX threads libraries and header files.])],[$1])
:
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ax_pthread_ok=no
$2
fi
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# ===========================================================================
# https://www.gnu.org/software/autoconf-archive/ax_require_defined.html
# ===========================================================================
#
# SYNOPSIS
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# AX_REQUIRE_DEFINED(MACRO)
#
# DESCRIPTION
#
# AX_REQUIRE_DEFINED is a simple helper for making sure other macros have
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# non-fatal:
#
# ./configure: line 1673: AX_CFLAGS_WARN_ALL: command not found
#
# It's like AC_REQUIRE except it doesn't expand the required macro.
#
# Here's an example:
#
# AX_REQUIRE_DEFINED([AX_CHECK_LINK_FLAG])
#
# LICENSE
#
# Copyright (c) 2014 Mike Frysinger <vapier@gentoo.org>
#
# Copying and distribution of this file, with or without modification, are
# permitted in any medium without royalty provided the copyright notice
# and this notice are preserved. This file is offered as-is, without any
# warranty.
#serial 2
AC_DEFUN([AX_REQUIRE_DEFINED], [dnl
m4_ifndef([$1], [m4_fatal([macro ]$1[ is not defined; is a m4 file missing?])])
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# Copyright (C) 2002-2021 Free Software Foundation, Inc.
#
# This file is free software; the Free Software Foundation
# gives unlimited permission to copy and/or distribute it,
# with or without modifications, as long as this notice is preserved.
# AM_AUTOMAKE_VERSION(VERSION)
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