1# SPDX-License-Identifier: GPL-3.0-or-later WITH Autoconf-exception-3.0 2# 3# =========================================================================== 4# https://www.gnu.org/software/autoconf-archive/ax_pthread.html 5# =========================================================================== 6# 7# SYNOPSIS 8# 9# AX_PTHREAD([ACTION-IF-FOUND[, ACTION-IF-NOT-FOUND]]) 10# 11# DESCRIPTION 12# 13# This macro figures out how to build C programs using POSIX threads. It 14# sets the PTHREAD_LIBS output variable to the threads library and linker 15# flags, and the PTHREAD_CFLAGS output variable to any special C compiler 16# flags that are needed. (The user can also force certain compiler 17# flags/libs to be tested by setting these environment variables.) 18# 19# Also sets PTHREAD_CC and PTHREAD_CXX to any special C compiler that is 20# needed for multi-threaded programs (defaults to the value of CC 21# respectively CXX otherwise). (This is necessary on e.g. AIX to use the 22# special cc_r/CC_r compiler alias.) 23# 24# NOTE: You are assumed to not only compile your program with these flags, 25# but also to link with them as well. For example, you might link with 26# $PTHREAD_CC $CFLAGS $PTHREAD_CFLAGS $LDFLAGS ... $PTHREAD_LIBS $LIBS 27# $PTHREAD_CXX $CXXFLAGS $PTHREAD_CFLAGS $LDFLAGS ... $PTHREAD_LIBS $LIBS 28# 29# If you are only building threaded programs, you may wish to use these 30# variables in your default LIBS, CFLAGS, and CC: 31# 32# LIBS="$PTHREAD_LIBS $LIBS" 33# CFLAGS="$CFLAGS $PTHREAD_CFLAGS" 34# CXXFLAGS="$CXXFLAGS $PTHREAD_CFLAGS" 35# CC="$PTHREAD_CC" 36# CXX="$PTHREAD_CXX" 37# 38# In addition, if the PTHREAD_CREATE_JOINABLE thread-attribute constant 39# has a nonstandard name, this macro defines PTHREAD_CREATE_JOINABLE to 40# that name (e.g. PTHREAD_CREATE_UNDETACHED on AIX). 41# 42# Also HAVE_PTHREAD_PRIO_INHERIT is defined if pthread is found and the 43# PTHREAD_PRIO_INHERIT symbol is defined when compiling with 44# PTHREAD_CFLAGS. 45# 46# ACTION-IF-FOUND is a list of shell commands to run if a threads library 47# is found, and ACTION-IF-NOT-FOUND is a list of commands to run it if it 48# is not found. If ACTION-IF-FOUND is not specified, the default action 49# will define HAVE_PTHREAD. 50# 51# Please let the authors know if this macro fails on any platform, or if 52# you have any other suggestions or comments. This macro was based on work 53# by SGJ on autoconf scripts for FFTW (http://www.fftw.org/) (with help 54# from M. Frigo), as well as ac_pthread and hb_pthread macros posted by 55# Alejandro Forero Cuervo to the autoconf macro repository. We are also 56# grateful for the helpful feedback of numerous users. 57# 58# Updated for Autoconf 2.68 by Daniel Richard G. 59# 60# LICENSE 61# 62# Copyright (c) 2008 Steven G. Johnson <stevenj@alum.mit.edu> 63# Copyright (c) 2011 Daniel Richard G. <skunk@iSKUNK.ORG> 64# Copyright (c) 2019 Marc Stevens <marc.stevens@cwi.nl> 65# 66# This program is free software: you can redistribute it and/or modify it 67# under the terms of the GNU General Public License as published by the 68# Free Software Foundation, either version 3 of the License, or (at your 69# option) any later version. 70# 71# This program is distributed in the hope that it will be useful, but 72# WITHOUT ANY WARRANTY; without even the implied warranty of 73# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General 74# Public License for more details. 75# 76# You should have received a copy of the GNU General Public License along 77# with this program. If not, see <https://www.gnu.org/licenses/>. 78# 79# As a special exception, the respective Autoconf Macro's copyright owner 80# gives unlimited permission to copy, distribute and modify the configure 81# scripts that are the output of Autoconf when processing the Macro. You 82# need not follow the terms of the GNU General Public License when using 83# or distributing such scripts, even though portions of the text of the 84# Macro appear in them. The GNU General Public License (GPL) does govern 85# all other use of the material that constitutes the Autoconf Macro. 86# 87# This special exception to the GPL applies to versions of the Autoconf 88# Macro released by the Autoconf Archive. When you make and distribute a 89# modified version of the Autoconf Macro, you may extend this special 90# exception to the GPL to apply to your modified version as well. 91 92#serial 30 93 94AU_ALIAS([ACX_PTHREAD], [AX_PTHREAD]) 95AC_DEFUN([AX_PTHREAD], [ 96AC_REQUIRE([AC_CANONICAL_TARGET]) 97AC_REQUIRE([AC_PROG_CC]) 98AC_REQUIRE([AC_PROG_SED]) 99AC_LANG_PUSH([C]) 100ax_pthread_ok=no 101 102# We used to check for pthread.h first, but this fails if pthread.h 103# requires special compiler flags (e.g. on Tru64 or Sequent). 104# It gets checked for in the link test anyway. 105 106# First of all, check if the user has set any of the PTHREAD_LIBS, 107# etcetera environment variables, and if threads linking works using 108# them: 109if test "x$PTHREAD_CFLAGS$PTHREAD_LIBS" != "x"; then 110 ax_pthread_save_CC="$CC" 111 ax_pthread_save_CFLAGS="$CFLAGS" 112 ax_pthread_save_LIBS="$LIBS" 113 AS_IF([test "x$PTHREAD_CC" != "x"], [CC="$PTHREAD_CC"]) 114 AS_IF([test "x$PTHREAD_CXX" != "x"], [CXX="$PTHREAD_CXX"]) 115 CFLAGS="$CFLAGS $PTHREAD_CFLAGS" 116 LIBS="$PTHREAD_LIBS $LIBS" 117 AC_MSG_CHECKING([for pthread_join using $CC $PTHREAD_CFLAGS $PTHREAD_LIBS]) 118 AC_LINK_IFELSE([AC_LANG_CALL([], [pthread_join])], [ax_pthread_ok=yes]) 119 AC_MSG_RESULT([$ax_pthread_ok]) 120 if test "x$ax_pthread_ok" = "xno"; then 121 PTHREAD_LIBS="" 122 PTHREAD_CFLAGS="" 123 fi 124 CC="$ax_pthread_save_CC" 125 CFLAGS="$ax_pthread_save_CFLAGS" 126 LIBS="$ax_pthread_save_LIBS" 127fi 128 129# We must check for the threads library under a number of different 130# names; the ordering is very important because some systems 131# (e.g. DEC) have both -lpthread and -lpthreads, where one of the 132# libraries is broken (non-POSIX). 133 134# Create a list of thread flags to try. Items with a "," contain both 135# C compiler flags (before ",") and linker flags (after ","). Other items 136# starting with a "-" are C compiler flags, and remaining items are 137# library names, except for "none" which indicates that we try without 138# any flags at all, and "pthread-config" which is a program returning 139# the flags for the Pth emulation library. 140 141ax_pthread_flags="pthreads none -Kthread -pthread -pthreads -mthreads pthread --thread-safe -mt pthread-config" 142 143# The ordering *is* (sometimes) important. Some notes on the 144# individual items follow: 145 146# pthreads: AIX (must check this before -lpthread) 147# none: in case threads are in libc; should be tried before -Kthread and 148# other compiler flags to prevent continual compiler warnings 149# -Kthread: Sequent (threads in libc, but -Kthread needed for pthread.h) 150# -pthread: Linux/gcc (kernel threads), BSD/gcc (userland threads), Tru64 151# (Note: HP C rejects this with "bad form for `-t' option") 152# -pthreads: Solaris/gcc (Note: HP C also rejects) 153# -mt: Sun Workshop C (may only link SunOS threads [-lthread], but it 154# doesn't hurt to check since this sometimes defines pthreads and 155# -D_REENTRANT too), HP C (must be checked before -lpthread, which 156# is present but should not be used directly; and before -mthreads, 157# because the compiler interprets this as "-mt" + "-hreads") 158# -mthreads: Mingw32/gcc, Lynx/gcc 159# pthread: Linux, etcetera 160# --thread-safe: KAI C++ 161# pthread-config: use pthread-config program (for GNU Pth library) 162 163case $target_os in 164 165 freebsd*) 166 167 # -kthread: FreeBSD kernel threads (preferred to -pthread since SMP-able) 168 # lthread: LinuxThreads port on FreeBSD (also preferred to -pthread) 169 170 ax_pthread_flags="-kthread lthread $ax_pthread_flags" 171 ;; 172 173 hpux*) 174 175 # From the cc(1) man page: "[-mt] Sets various -D flags to enable 176 # multi-threading and also sets -lpthread." 177 178 ax_pthread_flags="-mt -pthread pthread $ax_pthread_flags" 179 ;; 180 181 openedition*) 182 183 # IBM z/OS requires a feature-test macro to be defined in order to 184 # enable POSIX threads at all, so give the user a hint if this is 185 # not set. (We don't define these ourselves, as they can affect 186 # other portions of the system API in unpredictable ways.) 187 188 AC_EGREP_CPP([AX_PTHREAD_ZOS_MISSING], 189 [ 190# if !defined(_OPEN_THREADS) && !defined(_UNIX03_THREADS) 191 AX_PTHREAD_ZOS_MISSING 192# endif 193 ], 194 [AC_MSG_WARN([IBM z/OS requires -D_OPEN_THREADS or -D_UNIX03_THREADS to enable pthreads support.])]) 195 ;; 196 197 solaris*) 198 199 # On Solaris (at least, for some versions), libc contains stubbed 200 # (non-functional) versions of the pthreads routines, so link-based 201 # tests will erroneously succeed. (N.B.: The stubs are missing 202 # pthread_cleanup_push, or rather a function called by this macro, 203 # so we could check for that, but who knows whether they'll stub 204 # that too in a future libc.) So we'll check first for the 205 # standard Solaris way of linking pthreads (-mt -lpthread). 206 207 ax_pthread_flags="-mt,-lpthread pthread $ax_pthread_flags" 208 ;; 209esac 210 211# Are we compiling with Clang? 212 213AC_CACHE_CHECK([whether $CC is Clang], 214 [ax_cv_PTHREAD_CLANG], 215 [ax_cv_PTHREAD_CLANG=no 216 # Note that Autoconf sets GCC=yes for Clang as well as GCC 217 if test "x$GCC" = "xyes"; then 218 AC_EGREP_CPP([AX_PTHREAD_CC_IS_CLANG], 219 [/* Note: Clang 2.7 lacks __clang_[a-z]+__ */ 220# if defined(__clang__) && defined(__llvm__) 221 AX_PTHREAD_CC_IS_CLANG 222# endif 223 ], 224 [ax_cv_PTHREAD_CLANG=yes]) 225 fi 226 ]) 227ax_pthread_clang="$ax_cv_PTHREAD_CLANG" 228 229 230# GCC generally uses -pthread, or -pthreads on some platforms (e.g. SPARC) 231 232# Note that for GCC and Clang -pthread generally implies -lpthread, 233# except when -nostdlib is passed. 234# This is problematic using libtool to build C++ shared libraries with pthread: 235# [1] https://gcc.gnu.org/bugzilla/show_bug.cgi?id=25460 236# [2] https://bugzilla.redhat.com/show_bug.cgi?id=661333 237# [3] https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=468555 238# To solve this, first try -pthread together with -lpthread for GCC 239 240AS_IF([test "x$GCC" = "xyes"], 241 [ax_pthread_flags="-pthread,-lpthread -pthread -pthreads $ax_pthread_flags"]) 242 243# Clang takes -pthread (never supported any other flag), but we'll try with -lpthread first 244 245AS_IF([test "x$ax_pthread_clang" = "xyes"], 246 [ax_pthread_flags="-pthread,-lpthread -pthread"]) 247 248 249# The presence of a feature test macro requesting re-entrant function 250# definitions is, on some systems, a strong hint that pthreads support is 251# correctly enabled 252 253case $target_os in 254 darwin* | hpux* | linux* | osf* | solaris*) 255 ax_pthread_check_macro="_REENTRANT" 256 ;; 257 258 aix*) 259 ax_pthread_check_macro="_THREAD_SAFE" 260 ;; 261 262 *) 263 ax_pthread_check_macro="--" 264 ;; 265esac 266AS_IF([test "x$ax_pthread_check_macro" = "x--"], 267 [ax_pthread_check_cond=0], 268 [ax_pthread_check_cond="!defined($ax_pthread_check_macro)"]) 269 270 271if test "x$ax_pthread_ok" = "xno"; then 272for ax_pthread_try_flag in $ax_pthread_flags; do 273 274 case $ax_pthread_try_flag in 275 none) 276 AC_MSG_CHECKING([whether pthreads work without any flags]) 277 ;; 278 279 *,*) 280 PTHREAD_CFLAGS=`echo $ax_pthread_try_flag | sed "s/^\(.*\),\(.*\)$/\1/"` 281 PTHREAD_LIBS=`echo $ax_pthread_try_flag | sed "s/^\(.*\),\(.*\)$/\2/"` 282 AC_MSG_CHECKING([whether pthreads work with "$PTHREAD_CFLAGS" and "$PTHREAD_LIBS"]) 283 ;; 284 285 -*) 286 AC_MSG_CHECKING([whether pthreads work with $ax_pthread_try_flag]) 287 PTHREAD_CFLAGS="$ax_pthread_try_flag" 288 ;; 289 290 pthread-config) 291 AC_CHECK_PROG([ax_pthread_config], [pthread-config], [yes], [no]) 292 AS_IF([test "x$ax_pthread_config" = "xno"], [continue]) 293 PTHREAD_CFLAGS="`pthread-config --cflags`" 294 PTHREAD_LIBS="`pthread-config --ldflags` `pthread-config --libs`" 295 ;; 296 297 *) 298 AC_MSG_CHECKING([for the pthreads library -l$ax_pthread_try_flag]) 299 PTHREAD_LIBS="-l$ax_pthread_try_flag" 300 ;; 301 esac 302 303 ax_pthread_save_CFLAGS="$CFLAGS" 304 ax_pthread_save_LIBS="$LIBS" 305 CFLAGS="$CFLAGS $PTHREAD_CFLAGS" 306 LIBS="$PTHREAD_LIBS $LIBS" 307 308 # Check for various functions. We must include pthread.h, 309 # since some functions may be macros. (On the Sequent, we 310 # need a special flag -Kthread to make this header compile.) 311 # We check for pthread_join because it is in -lpthread on IRIX 312 # while pthread_create is in libc. We check for pthread_attr_init 313 # due to DEC craziness with -lpthreads. We check for 314 # pthread_cleanup_push because it is one of the few pthread 315 # functions on Solaris that doesn't have a non-functional libc stub. 316 # We try pthread_create on general principles. 317 318 AC_LINK_IFELSE([AC_LANG_PROGRAM([#include <pthread.h> 319# if $ax_pthread_check_cond 320# error "$ax_pthread_check_macro must be defined" 321# endif 322 static void *some_global = NULL; 323 static void routine(void *a) 324 { 325 /* To avoid any unused-parameter or 326 unused-but-set-parameter warning. */ 327 some_global = a; 328 } 329 static void *start_routine(void *a) { return a; }], 330 [pthread_t th; pthread_attr_t attr; 331 pthread_create(&th, 0, start_routine, 0); 332 pthread_join(th, 0); 333 pthread_attr_init(&attr); 334 pthread_cleanup_push(routine, 0); 335 pthread_cleanup_pop(0) /* ; */])], 336 [ax_pthread_ok=yes], 337 []) 338 339 CFLAGS="$ax_pthread_save_CFLAGS" 340 LIBS="$ax_pthread_save_LIBS" 341 342 AC_MSG_RESULT([$ax_pthread_ok]) 343 AS_IF([test "x$ax_pthread_ok" = "xyes"], [break]) 344 345 PTHREAD_LIBS="" 346 PTHREAD_CFLAGS="" 347done 348fi 349 350 351# Clang needs special handling, because older versions handle the -pthread 352# option in a rather... idiosyncratic way 353 354if test "x$ax_pthread_clang" = "xyes"; then 355 356 # Clang takes -pthread; it has never supported any other flag 357 358 # (Note 1: This will need to be revisited if a system that Clang 359 # supports has POSIX threads in a separate library. This tends not 360 # to be the way of modern systems, but it's conceivable.) 361 362 # (Note 2: On some systems, notably Darwin, -pthread is not needed 363 # to get POSIX threads support; the API is always present and 364 # active. We could reasonably leave PTHREAD_CFLAGS empty. But 365 # -pthread does define _REENTRANT, and while the Darwin headers 366 # ignore this macro, third-party headers might not.) 367 368 # However, older versions of Clang make a point of warning the user 369 # that, in an invocation where only linking and no compilation is 370 # taking place, the -pthread option has no effect ("argument unused 371 # during compilation"). They expect -pthread to be passed in only 372 # when source code is being compiled. 373 # 374 # Problem is, this is at odds with the way Automake and most other 375 # C build frameworks function, which is that the same flags used in 376 # compilation (CFLAGS) are also used in linking. Many systems 377 # supported by AX_PTHREAD require exactly this for POSIX threads 378 # support, and in fact it is often not straightforward to specify a 379 # flag that is used only in the compilation phase and not in 380 # linking. Such a scenario is extremely rare in practice. 381 # 382 # Even though use of the -pthread flag in linking would only print 383 # a warning, this can be a nuisance for well-run software projects 384 # that build with -Werror. So if the active version of Clang has 385 # this misfeature, we search for an option to squash it. 386 387 AC_CACHE_CHECK([whether Clang needs flag to prevent "argument unused" warning when linking with -pthread], 388 [ax_cv_PTHREAD_CLANG_NO_WARN_FLAG], 389 [ax_cv_PTHREAD_CLANG_NO_WARN_FLAG=unknown 390 # Create an alternate version of $ac_link that compiles and 391 # links in two steps (.c -> .o, .o -> exe) instead of one 392 # (.c -> exe), because the warning occurs only in the second 393 # step 394 ax_pthread_save_ac_link="$ac_link" 395 ax_pthread_sed='s/conftest\.\$ac_ext/conftest.$ac_objext/g' 396 ax_pthread_link_step=`AS_ECHO(["$ac_link"]) | sed "$ax_pthread_sed"` 397 ax_pthread_2step_ac_link="($ac_compile) && (echo ==== >&5) && ($ax_pthread_link_step)" 398 ax_pthread_save_CFLAGS="$CFLAGS" 399 for ax_pthread_try in '' -Qunused-arguments -Wno-unused-command-line-argument unknown; do 400 AS_IF([test "x$ax_pthread_try" = "xunknown"], [break]) 401 CFLAGS="-Werror -Wunknown-warning-option $ax_pthread_try -pthread $ax_pthread_save_CFLAGS" 402 ac_link="$ax_pthread_save_ac_link" 403 AC_LINK_IFELSE([AC_LANG_SOURCE([[int main(void){return 0;}]])], 404 [ac_link="$ax_pthread_2step_ac_link" 405 AC_LINK_IFELSE([AC_LANG_SOURCE([[int main(void){return 0;}]])], 406 [break]) 407 ]) 408 done 409 ac_link="$ax_pthread_save_ac_link" 410 CFLAGS="$ax_pthread_save_CFLAGS" 411 AS_IF([test "x$ax_pthread_try" = "x"], [ax_pthread_try=no]) 412 ax_cv_PTHREAD_CLANG_NO_WARN_FLAG="$ax_pthread_try" 413 ]) 414 415 case "$ax_cv_PTHREAD_CLANG_NO_WARN_FLAG" in 416 no | unknown) ;; 417 *) PTHREAD_CFLAGS="$ax_cv_PTHREAD_CLANG_NO_WARN_FLAG $PTHREAD_CFLAGS" ;; 418 esac 419 420fi # $ax_pthread_clang = yes 421 422 423 424# Various other checks: 425if test "x$ax_pthread_ok" = "xyes"; then 426 ax_pthread_save_CFLAGS="$CFLAGS" 427 ax_pthread_save_LIBS="$LIBS" 428 CFLAGS="$CFLAGS $PTHREAD_CFLAGS" 429 LIBS="$PTHREAD_LIBS $LIBS" 430 431 # Detect AIX lossage: JOINABLE attribute is called UNDETACHED. 432 AC_CACHE_CHECK([for joinable pthread attribute], 433 [ax_cv_PTHREAD_JOINABLE_ATTR], 434 [ax_cv_PTHREAD_JOINABLE_ATTR=unknown 435 for ax_pthread_attr in PTHREAD_CREATE_JOINABLE PTHREAD_CREATE_UNDETACHED; do 436 AC_LINK_IFELSE([AC_LANG_PROGRAM([#include <pthread.h>], 437 [int attr = $ax_pthread_attr; return attr /* ; */])], 438 [ax_cv_PTHREAD_JOINABLE_ATTR=$ax_pthread_attr; break], 439 []) 440 done 441 ]) 442 AS_IF([test "x$ax_cv_PTHREAD_JOINABLE_ATTR" != "xunknown" && \ 443 test "x$ax_cv_PTHREAD_JOINABLE_ATTR" != "xPTHREAD_CREATE_JOINABLE" && \ 444 test "x$ax_pthread_joinable_attr_defined" != "xyes"], 445 [AC_DEFINE_UNQUOTED([PTHREAD_CREATE_JOINABLE], 446 [$ax_cv_PTHREAD_JOINABLE_ATTR], 447 [Define to necessary symbol if this constant 448 uses a non-standard name on your system.]) 449 ax_pthread_joinable_attr_defined=yes 450 ]) 451 452 AC_CACHE_CHECK([whether more special flags are required for pthreads], 453 [ax_cv_PTHREAD_SPECIAL_FLAGS], 454 [ax_cv_PTHREAD_SPECIAL_FLAGS=no 455 case $target_os in 456 solaris*) 457 ax_cv_PTHREAD_SPECIAL_FLAGS="-D_POSIX_PTHREAD_SEMANTICS" 458 ;; 459 esac 460 ]) 461 AS_IF([test "x$ax_cv_PTHREAD_SPECIAL_FLAGS" != "xno" && \ 462 test "x$ax_pthread_special_flags_added" != "xyes"], 463 [PTHREAD_CFLAGS="$ax_cv_PTHREAD_SPECIAL_FLAGS $PTHREAD_CFLAGS" 464 ax_pthread_special_flags_added=yes]) 465 466 AC_CACHE_CHECK([for PTHREAD_PRIO_INHERIT], 467 [ax_cv_PTHREAD_PRIO_INHERIT], 468 [AC_LINK_IFELSE([AC_LANG_PROGRAM([[#include <pthread.h>]], 469 [[int i = PTHREAD_PRIO_INHERIT; 470 return i;]])], 471 [ax_cv_PTHREAD_PRIO_INHERIT=yes], 472 [ax_cv_PTHREAD_PRIO_INHERIT=no]) 473 ]) 474 AS_IF([test "x$ax_cv_PTHREAD_PRIO_INHERIT" = "xyes" && \ 475 test "x$ax_pthread_prio_inherit_defined" != "xyes"], 476 [AC_DEFINE([HAVE_PTHREAD_PRIO_INHERIT], [1], [Have PTHREAD_PRIO_INHERIT.]) 477 ax_pthread_prio_inherit_defined=yes 478 ]) 479 480 CFLAGS="$ax_pthread_save_CFLAGS" 481 LIBS="$ax_pthread_save_LIBS" 482 483 # More AIX lossage: compile with *_r variant 484 if test "x$GCC" != "xyes"; then 485 case $target_os in 486 aix*) 487 AS_CASE(["x/$CC"], 488 [x*/c89|x*/c89_128|x*/c99|x*/c99_128|x*/cc|x*/cc128|x*/xlc|x*/xlc_v6|x*/xlc128|x*/xlc128_v6], 489 [#handle absolute path differently from PATH based program lookup 490 AS_CASE(["x$CC"], 491 [x/*], 492 [ 493 AS_IF([AS_EXECUTABLE_P([${CC}_r])],[PTHREAD_CC="${CC}_r"]) 494 AS_IF([test "x${CXX}" != "x"], [AS_IF([AS_EXECUTABLE_P([${CXX}_r])],[PTHREAD_CXX="${CXX}_r"])]) 495 ], 496 [ 497 AC_CHECK_PROGS([PTHREAD_CC],[${CC}_r],[$CC]) 498 AS_IF([test "x${CXX}" != "x"], [AC_CHECK_PROGS([PTHREAD_CXX],[${CXX}_r],[$CXX])]) 499 ] 500 ) 501 ]) 502 ;; 503 esac 504 fi 505fi 506 507test -n "$PTHREAD_CC" || PTHREAD_CC="$CC" 508test -n "$PTHREAD_CXX" || PTHREAD_CXX="$CXX" 509 510AC_SUBST([PTHREAD_LIBS]) 511AC_SUBST([PTHREAD_CFLAGS]) 512AC_SUBST([PTHREAD_CC]) 513AC_SUBST([PTHREAD_CXX]) 514 515# Finally, execute ACTION-IF-FOUND/ACTION-IF-NOT-FOUND: 516if test "x$ax_pthread_ok" = "xyes"; then 517 ifelse([$1],,[AC_DEFINE([HAVE_PTHREAD],[1],[Define if you have POSIX threads libraries and header files.])],[$1]) 518 : 519else 520 ax_pthread_ok=no 521 $2 522fi 523AC_LANG_POP 524])dnl AX_PTHREAD 525