openmpi/config/ompi_setup_cxx.m4

dnl -*- shell-script -*-
dnl
dnl Copyright (c) 2004-2005 The Trustees of Indiana University.
dnl                         All rights reserved.
dnl Copyright (c) 2004-2005 The Trustees of the University of Tennessee.
dnl                         All rights reserved.
dnl Copyright (c) 2004-2005 High Performance Computing Center Stuttgart, 
dnl                         University of Stuttgart.  All rights reserved.
dnl Copyright (c) 2004-2005 The Regents of the University of California.
dnl                         All rights reserved.
dnl $COPYRIGHT$
dnl 
dnl Additional copyrights may follow
dnl 
dnl $HEADER$
dnl

AC_DEFUN([OMPI_SETUP_CXX],[

# Modularize this setup so that sub-configure.in scripts can use this
# same setup code.

ompi_show_subtitle "C++ compiler and preprocessor" 

ompi_cxxflags_save="$CXXFLAGS"
AC_PROG_CXX
AC_PROG_CXXCPP
BASECXX="`basename $CXX`"
CXXFLAGS="$ompi_cxxflags_save"
AC_DEFINE_UNQUOTED(OMPI_CXX, "$CXX", [OMPI underlying C++ compiler])

# Check for compilers that impersonate g++

AC_MSG_CHECKING([for compilers that impersonate g++])
msg=
TRULY_GXX=$GXX
if test "$GXX" = "yes"; then
    AC_TRY_COMPILE([], [
int i = 3;
#if __INTEL_COMPILER
#error Yes, I am lying about being g++.
#endif
], [], [msg=intel])

    # If we made it through unscathed, then it really is g++   
    if test -z "$msg"; then
        TRULY_GXX=yes
    else
        TRULY_GXX=no
    fi
else
    # We never thought that this was GXX to begin with
    msg="not applicable"
    TRULY_GXX=no
fi
AC_MSG_RESULT([$msg])

# Do we want code coverage
if test "$WANT_COVERAGE" = "1"; then 
     if test "$TRULY_GXX" = "yes"; then 
         AC_MSG_WARN([-fprofile-arcs -ftest-coverage has been added to CFLAGS (--enable-coverage)])
         WANT_DEBUG=1
         CXXFLAGS="-ftest-coverage -fprofile-arcs ${CXXFLAGS}"
         WRAPPER_EXTRA_CXXFLAGS="-ftest-coverage -fprofile-arcs ${WRAPPER_EXTRA_CXXFLAGS}"
      else
         AC_MSG_WARN([Code coverage functionality is currently available only with GCC suite])
         AC_MSG_ERROR([Configure: cannot continue])
      fi
fi

# Do we want debugging?

if test "$WANT_DEBUG" = "1"; then
    CXXFLAGS="$CXXFLAGS -g"
    OMPI_UNIQ(CXXFLAGS)
    AC_MSG_WARN([-g has been added to CXXFLAGS (--enable-debug)])
fi

# These flags are generally g++-specific; even the g++-impersonating
# compilers won't accept them.

OMPI_CXXFLAGS_BEFORE_PICKY="$CXXFLAGS"
if test "$TRULY_GXX" = "yes" -a "$WANT_PICKY_COMPILER" = 1; then
    add="-g -Wall -Wundef -Wno-long-long"

    # see if -Wno-long-double works...
    AC_LANG_PUSH(C++)
    CXXFLAGS_orig="$CXXFLAGS"
    CXXFLAGS="$CXXFLAGS -Wno-long-double"
    AC_TRY_COMPILE([], [], add="$add -Wno-long-double")
    CXXFLAGS="$CXXFLAGS_orig"
    AC_LANG_POP(C++)

    CXXFLAGS="$CXXFLAGS $add"
    OMPI_UNIQ(CXXFLAGS)
    AC_MSG_WARN([$add has been added to CXXFLAGS (--enable-picky)])
    unset add
fi

# See if this version of g++ allows -finline-functions

if test "$GXX" = "yes"; then
    CXXFLAGS_orig="$CXXFLAGS"
    CXXFLAGS="$CXXFLAGS -finline-functions"
    add=
    AC_TRY_COMPILE([], [], add=" -finline-functions")
    CXXFLAGS="$CXXFLAGS_orig$add"
    OMPI_UNIQ(CXXFLAGS)
    AC_MSG_WARN([$add has been added to CXXFLAGS])
    unset add
fi

# Check for special things due to C++ exceptions

ENABLE_CXX_EXCEPTIONS=no
HAVE_CXX_EXCEPTIONS=0
AC_ARG_ENABLE(cxx-exceptions, 
  AC_HELP_STRING([--enable-cxx-exceptions],
		 [enable support for C++ exceptions]),
  [ENABLE_CXX_EXCEPTIONS="$enableval"])

AC_MSG_CHECKING([if want C++ exception handling])
AC_MSG_RESULT([$ENABLE_CXX_EXCEPTIONS])
if test "$ENABLE_CXX_EXCEPTIONS" = "yes"; then
    # config/cxx_have_exceptions.m4
    OMPI_CXX_HAVE_EXCEPTIONS
    # config/cxx_find_exception_flags.m4
    OMPI_CXX_FIND_EXCEPTION_FLAGS
    if test "$OMPI_CXX_EXCEPTIONS" = "1"; then
	HAVE_CXX_EXCEPTIONS=1
	CFLAGS="$CFLAGS $OMPI_CXX_EXCEPTIONS_CFLAGS"
	FFLAGS="$FFLAGS $OMPI_CXX_EXCEPTIONS_FFLAGS"
	CXXFLAGS="$CXXFLAGS $OMPI_CXX_EXCEPTIONS_CXXFLAGS"
	LDFLAGS="$LDFLAGS $OMPI_CXX_EXCEPTIONS_LDFLAGS"

	WRAPPER_EXTRA_CFLAGS="$OMPI_CXX_EXCEPTIONS_CFLAGS ${WRAPPER_EXTRA_CFLAGS}"
	WRAPPER_EXTRA_FFLAGS="$OMPI_CXX_EXCEPTIONS_FFLAGS ${WRAPPER_EXTRA_FFLAGS}"
	WRAPPER_EXTRA_CXXFLAGS="$OMPI_CXX_EXCEPTIONS_CXXFLAGS ${WRAPPER_EXTRA_CXXFLAGS}"
    fi
fi
AC_DEFINE_UNQUOTED(OMPI_HAVE_CXX_EXCEPTION_SUPPORT, $HAVE_CXX_EXCEPTIONS,
    [Whether or not we have compiled with C++ exceptions support])

# Find some more characteristics of the C++ compiler

# config/cxx_find_template_repository.m4
OMPI_CXX_FIND_TEMPLATE_REPOSITORY
# config/cxx_find_template_parameters.m4
OMPI_CXX_FIND_TEMPLATE_PARAMETERS

# If we are on HP-UX, ensure that we're using aCC
case "$host" in
*hpux*)
    if test "$BASECXX" = "CC"; then
	AC_MSG_WARN([*** You will probably have problems compiling the MPI 2])
	AC_MSG_WARN([*** C++ bindings with the HP-UX CC compiler.  You should])
	AC_MSG_WARN([*** probably be using the aCC compiler.  Re-run configure])
	AC_MSG_WARN([*** with the environment variable "CXX=aCC".])
    fi
    ;;
esac

# Same rationale for g++ as with gcc in OMPI_SETUP_CC.

# Note: gcc-imperonating compilers accept -O3, so there's no need for
# $TRULY_GCC here.

if test "$GXX" = yes; then
    OPTFLAGS="-O3"
else
    OPTFLAGS="-O"
fi
# config/ompi_check_optflags.m4
OMPI_CHECK_OPTFLAGS("$CXXFLAGS")
AC_MSG_CHECKING([for C++ optimization flags])
AC_MSG_RESULT([$co_result])
CXXFLAGS="$co_result"
])