Changes to m4/ax_pthread.m4. All files

m4/ax_pthread.m4

new file mode 100644@@ -0,0 +1,522 @@+# ===========================================================================+#        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--"],+      [ax_pthread_check_cond=0],+      [ax_pthread_check_cond="!defined($ax_pthread_check_macro)"])+++if test "x$ax_pthread_ok" = "xno"; then+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"+#                       endif+                        static void *some_global = NULL;+                        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.++        AC_CACHE_CHECK([whether Clang needs flag to prevent "argument unused" warning when linking with -pthread],+            [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"+             CFLAGS="$ax_pthread_save_CFLAGS"+             AS_IF([test "x$ax_pthread_try" = "x"], [ax_pthread_try=no])+             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],+                                [])+             done+            ])+        AS_IF([test "x$ax_cv_PTHREAD_JOINABLE_ATTR" != "xunknown" && \+               test "x$ax_cv_PTHREAD_JOINABLE_ATTR" != "xPTHREAD_CREATE_JOINABLE" && \+               test "x$ax_pthread_joinable_attr_defined" != "xyes"],+              [AC_DEFINE_UNQUOTED([PTHREAD_CREATE_JOINABLE],+                                  [$ax_cv_PTHREAD_JOINABLE_ATTR],+                                  [Define to necessary symbol if this constant+                                   uses a non-standard name on your system.])+               ax_pthread_joinable_attr_defined=yes+              ])++        AC_CACHE_CHECK([whether more special flags are required for pthreads],+            [ax_cv_PTHREAD_SPECIAL_FLAGS],+            [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"])])+			 ],+                         [+			   AC_CHECK_PROGS([PTHREAD_CC],[${CC}_r],[$CC])+			   AS_IF([test "x${CXX}" != "x"], [AC_CHECK_PROGS([PTHREAD_CXX],[${CXX}_r],[$CXX])])+			 ]+                     )+                    ])+                ;;+            esac+        fi+fi++test -n "$PTHREAD_CC" || PTHREAD_CC="$CC"+test -n "$PTHREAD_CXX" || PTHREAD_CXX="$CXX"++AC_SUBST([PTHREAD_LIBS])+AC_SUBST([PTHREAD_CFLAGS])+AC_SUBST([PTHREAD_CC])+AC_SUBST([PTHREAD_CXX])++# Finally, execute ACTION-IF-FOUND/ACTION-IF-NOT-FOUND:+if test "x$ax_pthread_ok" = "xyes"; then+        ifelse([$1],,[AC_DEFINE([HAVE_PTHREAD],[1],[Define if you have POSIX threads libraries and header files.])],[$1])+        :+else+        ax_pthread_ok=no+        $2+fi+AC_LANG_POP+])dnl AX_PTHREAD