[lttng-dev] [PATCH urcu] Clean pthread detection

Mathieu Desnoyers mathieu.desnoyers at efficios.com
Thu Jun 23 01:52:15 UTC 2016


----- On Jun 22, 2016, at 6:36 PM, Michael Jeanson mjeanson at efficios.com wrote:

Hi Michael,

Can you re-send this patch CCing lttng-dev, and Charles Briere too,
so he can try it out on Android ?

Thanks,

Mathieu

> Signed-off-by: Michael Jeanson <mjeanson at efficios.com>
> ---
> Makefile.am                  |   3 -
> configure.ac                 |  14 --
> m4/ax_pthread.m4             | 385 ++++++++++++++++++++++++++++++-------------
> tests/benchmark/Makefile.am  |   3 -
> tests/regression/Makefile.am |   3 -
> tests/unit/Makefile.am       |   3 -
> 6 files changed, 269 insertions(+), 142 deletions(-)
> 
> diff --git a/Makefile.am b/Makefile.am
> index 8e25fd9..7b21321 100644
> --- a/Makefile.am
> +++ b/Makefile.am
> @@ -5,9 +5,6 @@ AM_CPPFLAGS = -I$(top_builddir)/urcu
> #Add the -version-info directly here since we are only building
> # library that use the version-info
> AM_LDFLAGS=-version-info $(URCU_LIBRARY_VERSION)
> -if !LIBC_INCLUDES_PTHREAD
> -AM_LDFLAGS+=-lpthread
> -endif
> if USE_CYGWIN
> AM_LDFLAGS+=-no-undefined
> endif
> diff --git a/configure.ac b/configure.ac
> index 639b984..95b0515 100644
> --- a/configure.ac
> +++ b/configure.ac
> @@ -140,11 +140,6 @@ AS_CASE([$host_cpu],
> 	[ARCHTYPE="unknown"]
> )
> 
> -AS_CASE([$host],[*-*-linux-androideabi],
> -	[AM_CONDITIONAL(TARGET_IS_ANDROID, true)],
> -	[AM_CONDITIONAL(TARGET_IS_ANDROID, false)]
> -)
> -
> AS_CASE([$host],[*-cygwin*],
> 	[AM_CONDITIONAL(USE_CYGWIN, true)],
> 	[AM_CONDITIONAL(USE_CYGWIN, false)]
> @@ -236,15 +231,6 @@ AC_SEARCH_LIBS([clock_gettime], [rt], [
> 	AC_DEFINE([CONFIG_RCU_HAVE_CLOCK_GETTIME], [1])
> ], [])
> 
> -# Check for pthread
> -AC_CHECK_LIB([pthread], [pthread_create],
> -	[AM_CONDITIONAL(LIBC_INCLUDES_PTHREAD, false)],
> -	[AC_CHECK_LIB([c], [pthread_create],
> -		[AM_CONDITIONAL(LIBC_INCLUDES_PTHREAD, true)],
> -		[AC_MSG_ERROR([Cannot find libpthread. Use [LDFLAGS]=-Ldir to specify its
> location.])]
> -	)]
> -)
> -
> AM_CONDITIONAL([COMPAT_FUTEX], [test "x$compat_futex_test" = "x1"])
> AM_CONDITIONAL([COMPAT_ARCH], [test "x$SUBARCHTYPE" = "xx86compat"])
> AM_CONDITIONAL([NO_SHARED], [test "x$enable_shared" = "xno"])
> diff --git a/m4/ax_pthread.m4 b/m4/ax_pthread.m4
> index d383ad5..4c4051e 100644
> --- a/m4/ax_pthread.m4
> +++ b/m4/ax_pthread.m4
> @@ -19,10 +19,10 @@
> #   is necessary on AIX to use the special cc_r compiler alias.)
> #
> #   NOTE: You are assumed to not only compile your program with these flags,
> -#   but also link it with them as well. e.g. you should link with
> +#   but also to link with them as well. For example, you might link with
> #   $PTHREAD_CC $CFLAGS $PTHREAD_CFLAGS $LDFLAGS ... $PTHREAD_LIBS $LIBS
> #
> -#   If you are only building threads programs, you may wish to use these
> +#   If you are only building threaded programs, you may wish to use these
> #   variables in your default LIBS, CFLAGS, and CC:
> #
> #     LIBS="$PTHREAD_LIBS $LIBS"
> @@ -30,8 +30,8 @@
> #     CC="$PTHREAD_CC"
> #
> #   In addition, if the PTHREAD_CREATE_JOINABLE thread-attribute constant
> -#   has a nonstandard name, defines PTHREAD_CREATE_JOINABLE to that name
> -#   (e.g. PTHREAD_CREATE_UNDETACHED on AIX).
> +#   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
> @@ -82,35 +82,40 @@
> #   modified version of the Autoconf Macro, you may extend this special
> #   exception to the GPL to apply to your modified version as well.
> 
> -#serial 21
> +#serial 23
> 
> 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 True64 or Sequent).
> +# 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"$PTHREAD_LIBS$PTHREAD_CFLAGS" != x; then
> -        save_CFLAGS="$CFLAGS"
> +if test "x$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"])
>         CFLAGS="$CFLAGS $PTHREAD_CFLAGS"
> -        save_LIBS="$LIBS"
>         LIBS="$PTHREAD_LIBS $LIBS"
> -        AC_MSG_CHECKING([for pthread_join in LIBS=$PTHREAD_LIBS with
> CFLAGS=$PTHREAD_CFLAGS])
> -        AC_TRY_LINK_FUNC([pthread_join], [ax_pthread_ok=yes])
> +        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"$ax_pthread_ok" = xno; then
> +        if test "x$ax_pthread_ok" = "xno"; then
>                 PTHREAD_LIBS=""
>                 PTHREAD_CFLAGS=""
>         fi
> -        LIBS="$save_LIBS"
> -        CFLAGS="$save_CFLAGS"
> +        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
> @@ -123,7 +128,7 @@ fi
> # 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 -kthread lthread -pthread -pthreads
> -mthreads pthread --thread-safe -mt pthread-config"
> +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:
> @@ -132,82 +137,225 @@ ax_pthread_flags="pthreads none -Kthread -kthread lthread
> -pthread -pthreads -mt
> # 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)
> -# -kthread: FreeBSD kernel threads (preferred to -pthread since SMP-able)
> -# lthread: LinuxThreads port on FreeBSD (also preferred to -pthread)
> -# -pthread: Linux/gcc (kernel threads), BSD/gcc (userland threads)
> -# -pthreads: Solaris/gcc
> -# -mthreads: Mingw32/gcc, Lynx/gcc
> +# -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 too;
> -#      also defines -D_REENTRANT)
> -#      ... -mt is also the pthreads flag for HP/aCC
> +#      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
> +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.  (We need to link with -pthreads/-mt/
> -        # -lpthread.)  (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 just look for -pthreads and -lpthread first:
> +        # 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,pthread pthread $ax_pthread_flags"
> +        ;;
> +esac
> +
> +# GCC generally uses -pthread, or -pthreads on some platforms (e.g. SPARC)
> 
> -        ax_pthread_flags="-pthreads pthread -mt -pthread $ax_pthread_flags"
> +AS_IF([test "x$GCC" = "xyes"],
> +      [ax_pthread_flags="-pthread -pthreads $ax_pthread_flags"])
> +
> +# 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"
>         ;;
> 
> -        darwin*)
> -        ax_pthread_flags="-pthread $ax_pthread_flags"
> +        aix*)
> +        ax_pthread_check_macro="_THREAD_SAFE"
> +        ;;
> +
> +        *)
> +        ax_pthread_check_macro="--"
>         ;;
> esac
> +AS_IF([test "x$ax_pthread_check_macro" = "x--"],
> +      [ax_pthread_check_cond=0],
> +      [ax_pthread_check_cond="!defined($ax_pthread_check_macro)"])
> +
> +# 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="$ax_cv_PTHREAD_CLANG"
> +
> +ax_pthread_clang_warning=no
> +
> +# Clang needs special handling, because older versions handle the -pthread
> +# option in a rather... idiosyncratic way
> +
> +if test "x$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.)
> +
> +        PTHREAD_CFLAGS="-pthread"
> +        PTHREAD_LIBS=
> +
> +        ax_pthread_ok=yes
> +
> +        # 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="$ax_pthread_try"
> +            ])
> 
> -# Clang doesn't consider unrecognized options an error unless we specify
> -# -Werror. We throw in some extra Clang-specific options to ensure that
> -# this doesn't happen for GCC, which also accepts -Werror.
> +        case "$ax_cv_PTHREAD_CLANG_NO_WARN_FLAG" in
> +                no | unknown) ;;
> +                *) PTHREAD_CFLAGS="$ax_cv_PTHREAD_CLANG_NO_WARN_FLAG
> $PTHREAD_CFLAGS" ;;
> +        esac
> 
> -AC_MSG_CHECKING([if compiler needs -Werror to reject unknown flags])
> -save_CFLAGS="$CFLAGS"
> -ax_pthread_extra_flags="-Werror"
> -CFLAGS="$CFLAGS $ax_pthread_extra_flags -Wunknown-warning-option
> -Wsizeof-array-argument"
> -AC_COMPILE_IFELSE([AC_LANG_PROGRAM([int foo(void);],[foo()])],
> -                  [AC_MSG_RESULT([yes])],
> -                  [ax_pthread_extra_flags=
> -                   AC_MSG_RESULT([no])])
> -CFLAGS="$save_CFLAGS"
> +fi # $ax_pthread_clang = yes
> 
> -if test x"$ax_pthread_ok" = xno; then
> -for flag in $ax_pthread_flags; do
> +if test "x$ax_pthread_ok" = "xno"; then
> +for ax_pthread_try_flag in $ax_pthread_flags; do
> 
> -        case $flag in
> +        case $ax_pthread_try_flag in
>                 none)
>                 AC_MSG_CHECKING([whether pthreads work without any flags])
>                 ;;
> 
> +                -mt,pthread)
> +                AC_MSG_CHECKING([whether pthreads work with -mt -lpthread])
> +                PTHREAD_CFLAGS="-mt"
> +                PTHREAD_LIBS="-lpthread"
> +                ;;
> +
>                 -*)
> -                AC_MSG_CHECKING([whether pthreads work with $flag])
> -                PTHREAD_CFLAGS="$flag"
> +                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])
> -                if test x"$ax_pthread_config" = xno; then continue; fi
> +                AS_IF([test "x$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$flag])
> -                PTHREAD_LIBS="-l$flag"
> +                AC_MSG_CHECKING([for the pthreads library
> -l$ax_pthread_try_flag])
> +                PTHREAD_LIBS="-l$ax_pthread_try_flag"
>                 ;;
>         esac
> 
> -        save_LIBS="$LIBS"
> -        save_CFLAGS="$CFLAGS"
> +        ax_pthread_save_CFLAGS="$CFLAGS"
> +        ax_pthread_save_LIBS="$LIBS"
> +        CFLAGS="$CFLAGS $PTHREAD_CFLAGS"
>         LIBS="$PTHREAD_LIBS $LIBS"
> -        CFLAGS="$CFLAGS $PTHREAD_CFLAGS $ax_pthread_extra_flags"
> 
>         # Check for various functions.  We must include pthread.h,
>         # since some functions may be macros.  (On the Sequent, we
> @@ -218,7 +366,11 @@ for flag in $ax_pthread_flags; do
>         # 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 routine(void *a) { a = 0; }
>                         static void *start_routine(void *a) { return a; }],
>                        [pthread_t th; pthread_attr_t attr;
> @@ -227,16 +379,14 @@ for flag in $ax_pthread_flags; do
>                         pthread_attr_init(&attr);
>                         pthread_cleanup_push(routine, 0);
>                         pthread_cleanup_pop(0) /* ; */])],
> -                [ax_pthread_ok=yes],
> -                [])
> +            [ax_pthread_ok=yes],
> +            [])
> 
> -        LIBS="$save_LIBS"
> -        CFLAGS="$save_CFLAGS"
> +        CFLAGS="$ax_pthread_save_CFLAGS"
> +        LIBS="$ax_pthread_save_LIBS"
> 
>         AC_MSG_RESULT([$ax_pthread_ok])
> -        if test "x$ax_pthread_ok" = xyes; then
> -                break;
> -        fi
> +        AS_IF([test "x$ax_pthread_ok" = "xyes"], [break])
> 
>         PTHREAD_LIBS=""
>         PTHREAD_CFLAGS=""
> @@ -244,71 +394,74 @@ done
> fi
> 
> # Various other checks:
> -if test "x$ax_pthread_ok" = xyes; then
> -        save_LIBS="$LIBS"
> -        LIBS="$PTHREAD_LIBS $LIBS"
> -        save_CFLAGS="$CFLAGS"
> +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_MSG_CHECKING([for joinable pthread attribute])
> -        attr_name=unknown
> -        for attr in PTHREAD_CREATE_JOINABLE PTHREAD_CREATE_UNDETACHED; do
> -            AC_LINK_IFELSE([AC_LANG_PROGRAM([#include <pthread.h>],
> -                           [int attr = $attr; return attr /* ; */])],
> -                [attr_name=$attr; break],
> -                [])
> -        done
> -        AC_MSG_RESULT([$attr_name])
> -        if test "$attr_name" != PTHREAD_CREATE_JOINABLE; then
> -            AC_DEFINE_UNQUOTED([PTHREAD_CREATE_JOINABLE], [$attr_name],
> -                               [Define to necessary symbol if this constant
> -                                uses a non-standard name on your system.])
> -        fi
> -
> -        AC_MSG_CHECKING([if more special flags are required for pthreads])
> -        flag=no
> -        case ${host_os} in
> -            aix* | freebsd* | darwin*) flag="-D_THREAD_SAFE";;
> -            osf* | hpux*) flag="-D_REENTRANT";;
> -            solaris*)
> -            if test "$GCC" = "yes"; then
> -                flag="-D_REENTRANT"
> -            else
> -                # TODO: What about Clang on Solaris?
> -                flag="-mt -D_REENTRANT"
> -            fi
> -            ;;
> -        esac
> -        AC_MSG_RESULT([$flag])
> -        if test "x$flag" != xno; then
> -            PTHREAD_CFLAGS="$flag $PTHREAD_CFLAGS"
> -        fi
> +        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 $PTHREAD_CFLAGS"
> +               ax_pthread_special_flags_added=yes])
> 
>         AC_CACHE_CHECK([for PTHREAD_PRIO_INHERIT],
> -            [ax_cv_PTHREAD_PRIO_INHERIT], [
> -                AC_LINK_IFELSE([AC_LANG_PROGRAM([[#include <pthread.h>]],
> -                                                [[int i =
> PTHREAD_PRIO_INHERIT;]])],
> -                    [ax_cv_PTHREAD_PRIO_INHERIT=yes],
> -                    [ax_cv_PTHREAD_PRIO_INHERIT=no])
> +            [ax_cv_PTHREAD_PRIO_INHERIT],
> +            [AC_LINK_IFELSE([AC_LANG_PROGRAM([[#include <pthread.h>]],
> +                                             [[int i =
> PTHREAD_PRIO_INHERIT;]])],
> +                            [ax_cv_PTHREAD_PRIO_INHERIT=yes],
> +                            [ax_cv_PTHREAD_PRIO_INHERIT=no])
>             ])
> -        AS_IF([test "x$ax_cv_PTHREAD_PRIO_INHERIT" = "xyes"],
> -            [AC_DEFINE([HAVE_PTHREAD_PRIO_INHERIT], [1], [Have
> PTHREAD_PRIO_INHERIT.])])
> +        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
> +              ])
> 
> -        LIBS="$save_LIBS"
> -        CFLAGS="$save_CFLAGS"
> +        CFLAGS="$ax_pthread_save_CFLAGS"
> +        LIBS="$ax_pthread_save_LIBS"
> 
>         # More AIX lossage: compile with *_r variant
> -        if test "x$GCC" != xyes; then
> +        if test "x$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="${CC}_r"])],
> -                     [AC_CHECK_PROGS([PTHREAD_CC],[${CC}_r],[$CC])])])
> +
> [x*/c89|x*/c89_128|x*/c99|x*/c99_128|x*/cc|x*/cc128|x*/xlc|x*/xlc_v6|x*/xlc128|x*/xlc128_v6],
> +                    [#handle absolute path differently from PATH based program
> lookup
> +                     AS_CASE(["x$CC"],
> +                         [x/*],
> +
> [AS_IF([AS_EXECUTABLE_P([${CC}_r])],[PTHREAD_CC="${CC}_r"])],
> +                         [AC_CHECK_PROGS([PTHREAD_CC],[${CC}_r],[$CC])])])
>                 ;;
>             esac
>         fi
> @@ -321,7 +474,7 @@ AC_SUBST([PTHREAD_CFLAGS])
> AC_SUBST([PTHREAD_CC])
> 
> # Finally, execute ACTION-IF-FOUND/ACTION-IF-NOT-FOUND:
> -if test x"$ax_pthread_ok" = xyes; then
> +if test "x$ax_pthread_ok" = "xyes"; then
>         ifelse([$1],,[AC_DEFINE([HAVE_PTHREAD],[1],[Define if you have POSIX threads
>         libraries and header files.])],[$1])
>         :
> else
> diff --git a/tests/benchmark/Makefile.am b/tests/benchmark/Makefile.am
> index 2326721..f513ed4 100644
> --- a/tests/benchmark/Makefile.am
> +++ b/tests/benchmark/Makefile.am
> @@ -1,6 +1,3 @@
> -if !LIBC_INCLUDES_PTHREAD
> -AM_LDFLAGS=-lpthread
> -endif
> AM_CFLAGS=-I$(top_srcdir) -I$(top_builddir) -I$(top_srcdir)/tests/common -g
> 
> SCRIPT_LIST = common.sh \
> diff --git a/tests/regression/Makefile.am b/tests/regression/Makefile.am
> index 2376edc..9556e3c 100644
> --- a/tests/regression/Makefile.am
> +++ b/tests/regression/Makefile.am
> @@ -1,6 +1,3 @@
> -if !LIBC_INCLUDES_PTHREAD
> -AM_LDFLAGS=-lpthread
> -endif
> AM_CFLAGS=-I$(top_srcdir) -I$(top_builddir) -I$(top_srcdir)/tests/utils
> -I$(top_srcdir)/tests/common -g
> 
> SCRIPT_LIST = run.sh
> diff --git a/tests/unit/Makefile.am b/tests/unit/Makefile.am
> index 08a3cba..d97e43f 100644
> --- a/tests/unit/Makefile.am
> +++ b/tests/unit/Makefile.am
> @@ -1,6 +1,3 @@
> -if !LIBC_INCLUDES_PTHREAD
> -AM_LDFLAGS=-lpthread
> -endif
> AM_CFLAGS=-I$(top_srcdir) -I$(top_builddir) -I$(top_srcdir)/tests/utils
> -I$(top_srcdir)/tests/common -g
> 
> SCRIPT_LIST = test_loop run.sh unit_tests
> --
> 2.7.4

-- 
Mathieu Desnoyers
EfficiOS Inc.
http://www.efficios.com


More information about the lttng-dev mailing list