Ralf Wildenhues wrote: > > Yes, they sell a port of XLC for Linux [1]. But I have no > > info about the command-line option for OpenMP in this compiler. > > [1] > http://www-306.ibm.com/software/info/ecatalog/en_US/products/Q860134T18351F02.html?&S_TACT=none&S_CMP=none > > As per > <http://www-1.ibm.com/support/docview.wss?rs=2239&context=SSJT9L&dc=DA410&uid=swg27007011&loc=en_US&cs=utf-8&lang=en> > > it uses -qsmp=omp as well. As per > <http://predef.sourceforge.net/precomp.html#sec17>, > you should be able to use __xlC__ or __IBMC__ / __IBMCPP__ I guess. Thanks for this info; it's integrated in the patch in the other mail. (I see that xlc and xlC define both __xlc__ and __xlC__.) > I've only now found this macro which seems to already have done this step: > <http://autoconf-archive.cryp.to/ax_openmp.html>. > Sorry it did not occur to me earlier, that approach looks like the > canonical way to generalize it to Fortran and C++. Find attached a draft, that still works in C and might work for C++. For Fortran, I don't know how to distinguish the various compiler brands. The GNU one can be tested through $ac_compiler_gnu, I suppose? But the others? > FYI, the potential downside of this is that one can easily forget to add > $OPENMP_CFLAGS to CFLAGS before the next compile test that may have a > different outcome depending on this. This is not a big problems: Such mistakes will become apparent immediately, because no compiler I know of has OpenMP support enabled by default. > make check TESTSUITEFLAGS='-k AC_C_OPENMP -v -d -x' This fails, apparently because the variables OPENMP_CFLAGS and enable_openmp (which you told me to use instead of ac_openmp_choice) are not inside autoconf's namespace. You know how to fix the testsuite? Bruno 2007-05-17 Bruno Haible <bruno@xxxxxxxxx> * lib/autoconf/c.m4 (_AC_LANG_OPENMP, AC_OPENMP): New macros. * doc/autoconf.texi (Generic Compiler Characteristics): Document AC_OPENMP. * NEWS: Mention AC_OPENMP. *** NEWS 14 May 2007 16:54:55 -0000 1.428 --- NEWS 17 May 2007 22:44:22 -0000 *************** *** 1,5 **** --- 1,7 ---- * Major changes in Autoconf 2.61b (????-??-??) + ** New macro AC_OPENMP. + ** AC_C_BIGENDIAN now supports universal binaries a la Mac OS X. ** AC_C_RESTRICT now prefers to #define 'restrict' to a variant spelling *** doc/autoconf.texi 14 May 2007 16:54:55 -0000 1.1154 --- doc/autoconf.texi 17 May 2007 22:44:30 -0000 *************** *** 6259,6264 **** --- 6259,6300 ---- Execute @var{action-if-fails} if the value cannot be determined correctly. @end defmac + @defmac AC_OPENMP + @acindex{OPENMP} + @cvindex _OPENMP + OpenMP (@url{http://www.openmp.org/}) is an extension of the C, C++, and + Fortran languages that makes it possible to optimize programs for Shared + Multiprocessing architectures, such as multi-core CPUs, with very small + effort. + + If the current language is set to C, the macro @code{AC_OPENMP} sets the + variable @code{OPENMP_CFLAGS} to the C compiler flags needed for supporting + OpenMP. If the compiler already supports OpenMP or if it has no way to + activate OpenMP support, @code{OPENMP_CFLAGS} is set to empty. Also, the + user can reject OpenMP support if it is not the default, by invoking + @samp{configure} with the @samp{--disable-openmp} option; then + @code{OPENMP_CFLAGS} is set to empty as well. + + The @code{OPENMP_CFLAGS} need to be used when compiling programs, when + preprocessing program source, and when linking programs. Therefore you + need to add them to the @code{CFLAGS} and @code{CPPFLAGS} of your programs + that use OpenMP. The presence of OpenMP support at compile time is revealed + by the preprocessor macro @code{_OPENMP}. + + Linking a program with @code{OPENMP_CFLAGS} typically adds one more shared + library to the program's dependencies, therefore its use is recommended only + on programs that actually use code conditional on @code{#ifdef _OPENMP}. + + If the current language is set to C++, @code{AC_OPENMP} sets the variable + @code{OPENMP_CXXFLAGS}, suitably for the C++ compiler. The same remarks + hold as for C. + + If the current language is set to Fortran 77 or Fortran, @code{AC_OPENMP} + sets the variable @code{OPENMP_FFLAGS} or @code{OPENMP_FCFLAGS}, respectively. + Similar remarks as for C hold, except that @code{CPPFLAGS} is not used for + Fortran, and there is no preprocessor macro signalling the support of OpenMP. + @end defmac + @defmac AC_LANG_WERROR @acindex{LANG_WERROR} Normally Autoconf ignores warnings generated by the compiler, linker, and *** lib/autoconf/c.m4 14 May 2007 16:54:55 -0000 1.247 --- lib/autoconf/c.m4 17 May 2007 22:44:31 -0000 *************** *** 1841,1843 **** --- 1841,1965 ---- fi fi ]) + + + # _AC_LANG_OPENMP + # --------------- + # Expands to some language dependent source code for testing the presence of + # OpenMP. + AC_DEFUN([_AC_LANG_OPENMP], + [_AC_LANG_DISPATCH([$0], _AC_LANG, $@)]) + + # _AC_LANG_OPENMP(C) + # ------------------ + m4_define([_AC_LANG_OPENMP(C)], + [ + #ifndef _OPENMP + choke me + #endif + #include <omp.h> + int main () { return omp_get_num_threads (); } + ]) + + # _AC_LANG_OPENMP(C++) + # -------------------- + m4_copy([_AC_LANG_OPENMP(C)], [_AC_LANG_OPENMP(C++)]) + + # _AC_LANG_OPENMP(Fortran 77) + # --------------------------- + m4_define([_AC_LANG_OPENMP(Fortran 77)], + [AC_LANG_FUNC_LINK_TRY([omp_get_num_threads])]) + + # _AC_LANG_OPENMP(Fortran) + # --------------------------- + m4_copy([_AC_LANG_OPENMP(Fortran 77)], [_AC_LANG_OPENMP(Fortran)]) + + # AC_OPENMP + # --------- + # Check which options need to be passed to the C compiler to support OpenMP. + # Set the OPENMP_CFLAGS / OPENMP_CXXFLAGS / OPENMP_FFLAGS variable to these + # options. + # The options are necessary at compile time (so the #pragmas are understood) + # and at link time (so the appropriate library is linked with). + # This macro takes care to not produce redundant options if $CC $CFLAGS already + # supports OpenMP. It also is careful to not pass options to compilers that + # misinterpret them; for example, most compilers accept "-openmp" and create + # an output file called 'penmp' rather than activating OpenMP support. + AC_DEFUN([AC_OPENMP], + [ + AC_MSG_CHECKING([whether to use OpenMP]) + AC_ARG_ENABLE(openmp, + [AS_HELP_STRING([--disable-openmp], [do not use OpenMP])], + [], + [enable_openmp=yes]) + AC_MSG_RESULT([$enable_openmp]) + OPENMP_[]_AC_LANG_PREFIX[]FLAGS= + if test "$enable_openmp" = yes; then + AC_MSG_CHECKING([for $CC option to support OpenMP]) + AC_CACHE_VAL([ac_cv_prog_[]_AC_LANG_ABBREV[]_openmp], [ + ac_cv_prog_[]_AC_LANG_ABBREV[]_openmp=unsupported + AC_LINK_IFELSE([_AC_LANG_OPENMP], + [ac_cv_prog_[]_AC_LANG_ABBREV[]_openmp="none needed"]) + if test "$ac_cv_prog_[]_AC_LANG_ABBREV[]_openmp" = unsupported; then + dnl Try these flags: + dnl GCC >= 4.2 -fopenmp + dnl SunPRO C -xopenmp + dnl Intel C -openmp + dnl SGI C, PGI C -mp + dnl Tru64 Compaq C -omp + dnl IBM C (AIX, Linux) -qsmp=omp + for ac_brand in GCC SunPRO Intel SGI/PGI Compaq IBM; do + case $ac_brand in + GCC) + ac_conditional='defined __GNUC__' + ac_option='-fopenmp' ;; + SunPRO) + ac_conditional='defined __SUNPRO_C || defined __SUNPRO_CC' + ac_option='-xopenmp' ;; + Intel) + ac_conditional='defined __INTEL_COMPILER' + ac_option='-openmp' ;; + SGI/PGI) + ac_conditional='defined __sgi || defined __PGI || defined __PGIC__' + ac_option='-mp' ;; + Compaq) + ac_conditional='defined __DECC || defined __DECCXX' + ac_option='-omp' ;; + IBM) + ac_conditional='defined __xlc__ || defined __xlC__' + ac_option='-qsmp=omp' ;; + esac + if test $ac_brand = GCC; then + if test "$ac_compiler_gnu" = yes; then + ac_openmp_result=yes + else + ac_openmp_result=no + fi + else + AC_EGREP_CPP([Brand], [ + #if $ac_conditional + Brand + #endif + ], [ac_openmp_result=yes], [ac_openmp_result=no]) + fi + if test $ac_openmp_result = yes; then + ac_save_[]_AC_LANG_PREFIX[]FLAGS=$[]_AC_LANG_PREFIX[]FLAGS + _AC_LANG_PREFIX[]FLAGS="$[]_AC_LANG_PREFIX[]FLAGS $ac_option" + AC_LINK_IFELSE([_AC_LANG_OPENMP], + [ac_cv_prog_[]_AC_LANG_ABBREV[]_openmp=$ac_option]) + _AC_LANG_PREFIX[]FLAGS=$ac_save_[]_AC_LANG_PREFIX[]FLAGS + break + fi + done + fi + ]) + AC_MSG_RESULT([$ac_cv_prog_[]_AC_LANG_ABBREV[]_openmp]) + case $ac_cv_prog_[]_AC_LANG_ABBREV[]_openmp in + "none needed" | unsupported) + OPENMP_[]_AC_LANG_PREFIX[]FLAGS= ;; + *) + OPENMP_[]_AC_LANG_PREFIX[]FLAGS=$ac_cv_prog_[]_AC_LANG_ABBREV[]_openmp ;; + esac + fi + AC_SUBST([OPENMP_]_AC_LANG_PREFIX[FLAGS]) + ]) _______________________________________________ Autoconf mailing list Autoconf@xxxxxxx http://lists.gnu.org/mailman/listinfo/autoconf
