CMake/Modules/FindMPI.cmake
Brad King 1c46b6aed0 FindMPI: Drop unnecessary and incorrect use of GetPrerequisites
Since commit v2.8.5~121^2~2 (FindMPI: Handle multiple languages,
2010-12-29) we called the GetPrerequisites is_file_executable function
but passed the name of a CMake variable instead of its value.  Therefore
the function has always failed and caused the search for the compiler
name to run even with an absolute path.  Switch to using if(IS_ABSOLUTE)
instead and drop use of GetPrerequisites.
2015-07-31 09:50:31 -04:00

664 lines
30 KiB
CMake

#.rst:
# FindMPI
# -------
#
# Find a Message Passing Interface (MPI) implementation
#
# The Message Passing Interface (MPI) is a library used to write
# high-performance distributed-memory parallel applications, and is
# typically deployed on a cluster. MPI is a standard interface (defined
# by the MPI forum) for which many implementations are available. All
# of them have somewhat different include paths, libraries to link
# against, etc., and this module tries to smooth out those differences.
#
# === Variables ===
#
# This module will set the following variables per language in your
# project, where <lang> is one of C, CXX, or Fortran:
#
# ::
#
# MPI_<lang>_FOUND TRUE if FindMPI found MPI flags for <lang>
# MPI_<lang>_COMPILER MPI Compiler wrapper for <lang>
# MPI_<lang>_COMPILE_FLAGS Compilation flags for MPI programs
# MPI_<lang>_INCLUDE_PATH Include path(s) for MPI header
# MPI_<lang>_LINK_FLAGS Linking flags for MPI programs
# MPI_<lang>_LIBRARIES All libraries to link MPI programs against
#
# Additionally, FindMPI sets the following variables for running MPI
# programs from the command line:
#
# ::
#
# MPIEXEC Executable for running MPI programs
# MPIEXEC_NUMPROC_FLAG Flag to pass to MPIEXEC before giving
# it the number of processors to run on
# MPIEXEC_PREFLAGS Flags to pass to MPIEXEC directly
# before the executable to run.
# MPIEXEC_POSTFLAGS Flags to pass to MPIEXEC after other flags
#
# === Usage ===
#
# To use this module, simply call FindMPI from a CMakeLists.txt file, or
# run find_package(MPI), then run CMake. If you are happy with the
# auto- detected configuration for your language, then you're done. If
# not, you have two options:
#
# ::
#
# 1. Set MPI_<lang>_COMPILER to the MPI wrapper (mpicc, etc.) of your
# choice and reconfigure. FindMPI will attempt to determine all the
# necessary variables using THAT compiler's compile and link flags.
# 2. If this fails, or if your MPI implementation does not come with
# a compiler wrapper, then set both MPI_<lang>_LIBRARIES and
# MPI_<lang>_INCLUDE_PATH. You may also set any other variables
# listed above, but these two are required. This will circumvent
# autodetection entirely.
#
# When configuration is successful, MPI_<lang>_COMPILER will be set to
# the compiler wrapper for <lang>, if it was found. MPI_<lang>_FOUND
# and other variables above will be set if any MPI implementation was
# found for <lang>, regardless of whether a compiler was found.
#
# When using MPIEXEC to execute MPI applications, you should typically
# use all of the MPIEXEC flags as follows:
#
# ::
#
# ${MPIEXEC} ${MPIEXEC_NUMPROC_FLAG} PROCS
# ${MPIEXEC_PREFLAGS} EXECUTABLE ${MPIEXEC_POSTFLAGS} ARGS
#
# where PROCS is the number of processors on which to execute the
# program, EXECUTABLE is the MPI program, and ARGS are the arguments to
# pass to the MPI program.
#
# === Backward Compatibility ===
#
# For backward compatibility with older versions of FindMPI, these
# variables are set, but deprecated:
#
# ::
#
# MPI_FOUND MPI_COMPILER MPI_LIBRARY
# MPI_COMPILE_FLAGS MPI_INCLUDE_PATH MPI_EXTRA_LIBRARY
# MPI_LINK_FLAGS MPI_LIBRARIES
#
# In new projects, please use the MPI_<lang>_XXX equivalents.
#=============================================================================
# Copyright 2001-2011 Kitware, Inc.
# Copyright 2010-2011 Todd Gamblin tgamblin@llnl.gov
# Copyright 2001-2009 Dave Partyka
#
# Distributed under the OSI-approved BSD License (the "License");
# see accompanying file Copyright.txt for details.
#
# This software is distributed WITHOUT ANY WARRANTY; without even the
# implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
# See the License for more information.
#=============================================================================
# (To distribute this file outside of CMake, substitute the full
# License text for the above reference.)
# include this to handle the QUIETLY and REQUIRED arguments
include(${CMAKE_CURRENT_LIST_DIR}/FindPackageHandleStandardArgs.cmake)
#
# This part detects MPI compilers, attempting to wade through the mess of compiler names in
# a sensible way.
#
# The compilers are detected in this order:
#
# 1. Try to find the most generic available MPI compiler, as this is usually set up by
# cluster admins. e.g., if plain old mpicc is available, we'll use it and assume it's
# the right compiler.
#
# 2. If a generic mpicc is NOT found, then we attempt to find one that matches
# CMAKE_<lang>_COMPILER_ID. e.g. if you are using XL compilers, we'll try to find mpixlc
# and company, but not mpiicc. This hopefully prevents toolchain mismatches.
#
# If you want to force a particular MPI compiler other than what we autodetect (e.g. if you
# want to compile regular stuff with GNU and parallel stuff with Intel), you can always set
# your favorite MPI_<lang>_COMPILER explicitly and this stuff will be ignored.
#
# Start out with the generic MPI compiler names, as these are most commonly used.
set(_MPI_C_COMPILER_NAMES mpicc mpcc mpicc_r mpcc_r)
set(_MPI_CXX_COMPILER_NAMES mpicxx mpiCC mpcxx mpCC mpic++ mpc++
mpicxx_r mpiCC_r mpcxx_r mpCC_r mpic++_r mpc++_r)
set(_MPI_Fortran_COMPILER_NAMES mpif95 mpif95_r mpf95 mpf95_r
mpif90 mpif90_r mpf90 mpf90_r
mpif77 mpif77_r mpf77 mpf77_r)
# GNU compiler names
set(_MPI_GNU_C_COMPILER_NAMES mpigcc mpgcc mpigcc_r mpgcc_r)
set(_MPI_GNU_CXX_COMPILER_NAMES mpig++ mpg++ mpig++_r mpg++_r)
set(_MPI_GNU_Fortran_COMPILER_NAMES mpigfortran mpgfortran mpigfortran_r mpgfortran_r
mpig77 mpig77_r mpg77 mpg77_r)
# Intel MPI compiler names
set(_MPI_Intel_C_COMPILER_NAMES mpiicc)
set(_MPI_Intel_CXX_COMPILER_NAMES mpiicpc mpiicxx mpiic++ mpiiCC)
set(_MPI_Intel_Fortran_COMPILER_NAMES mpiifort mpiif95 mpiif90 mpiif77)
# PGI compiler names
set(_MPI_PGI_C_COMPILER_NAMES mpipgcc mppgcc)
set(_MPI_PGI_CXX_COMPILER_NAMES mpipgCC mppgCC)
set(_MPI_PGI_Fortran_COMPILER_NAMES mpipgf95 mpipgf90 mppgf95 mppgf90 mpipgf77 mppgf77)
# XLC MPI Compiler names
set(_MPI_XL_C_COMPILER_NAMES mpxlc mpxlc_r mpixlc mpixlc_r)
set(_MPI_XL_CXX_COMPILER_NAMES mpixlcxx mpixlC mpixlc++ mpxlcxx mpxlc++ mpixlc++ mpxlCC
mpixlcxx_r mpixlC_r mpixlc++_r mpxlcxx_r mpxlc++_r mpixlc++_r mpxlCC_r)
set(_MPI_XL_Fortran_COMPILER_NAMES mpixlf95 mpixlf95_r mpxlf95 mpxlf95_r
mpixlf90 mpixlf90_r mpxlf90 mpxlf90_r
mpixlf77 mpixlf77_r mpxlf77 mpxlf77_r
mpixlf mpixlf_r mpxlf mpxlf_r)
# append vendor-specific compilers to the list if we either don't know the compiler id,
# or if we know it matches the regular compiler.
foreach (lang C CXX Fortran)
foreach (id GNU Intel PGI XL)
if (NOT CMAKE_${lang}_COMPILER_ID OR CMAKE_${lang}_COMPILER_ID STREQUAL id)
list(APPEND _MPI_${lang}_COMPILER_NAMES ${_MPI_${id}_${lang}_COMPILER_NAMES})
endif()
unset(_MPI_${id}_${lang}_COMPILER_NAMES) # clean up the namespace here
endforeach()
endforeach()
# Names to try for MPI exec
set(_MPI_EXEC_NAMES mpiexec mpirun lamexec srun)
# Grab the path to MPI from the registry if we're on windows.
set(_MPI_PREFIX_PATH)
if(WIN32)
# MSMPI
file(TO_CMAKE_PATH "$ENV{MSMPI_BIN}" msmpi_bin_path) # The default path ends with a '\' and doesn't mix with ';' when appending.
list(APPEND _MPI_PREFIX_PATH "${msmpi_bin_path}")
unset(msmpi_bin_path)
list(APPEND _MPI_PREFIX_PATH "[HKEY_LOCAL_MACHINE\\SOFTWARE\\Microsoft\\MPI;InstallRoot]/Bin")
list(APPEND _MPI_PREFIX_PATH "$ENV{MSMPI_INC}/..") # The SDK is installed separately from the runtime
# MPICH
list(APPEND _MPI_PREFIX_PATH "[HKEY_LOCAL_MACHINE\\SOFTWARE\\MPICH\\SMPD;binary]/..")
list(APPEND _MPI_PREFIX_PATH "[HKEY_LOCAL_MACHINE\\SOFTWARE\\MPICH2;Path]")
list(APPEND _MPI_PREFIX_PATH "$ENV{ProgramW6432}/MPICH2/")
endif()
# Build a list of prefixes to search for MPI.
foreach(SystemPrefixDir ${CMAKE_SYSTEM_PREFIX_PATH})
foreach(MpiPackageDir ${_MPI_PREFIX_PATH})
if(EXISTS ${SystemPrefixDir}/${MpiPackageDir})
list(APPEND _MPI_PREFIX_PATH "${SystemPrefixDir}/${MpiPackageDir}")
endif()
endforeach()
endforeach()
function (_mpi_check_compiler compiler options cmdvar resvar)
execute_process(
COMMAND "${compiler}" ${options}
OUTPUT_VARIABLE cmdline OUTPUT_STRIP_TRAILING_WHITESPACE
ERROR_VARIABLE cmdline ERROR_STRIP_TRAILING_WHITESPACE
RESULT_VARIABLE success)
# Intel MPI 5.0.1 will return a zero return code even when the
# argument to the MPI compiler wrapper is unknown. Attempt to
# catch this case.
if(cmdline MATCHES "undefined reference" OR cmdline MATCHES "unrecognized")
set(success 255 )
endif()
set(${cmdvar} "${cmdline}" PARENT_SCOPE)
set(${resvar} "${success}" PARENT_SCOPE)
endfunction()
#
# interrogate_mpi_compiler(lang try_libs)
#
# Attempts to extract compiler and linker args from an MPI compiler. The arguments set
# by this function are:
#
# MPI_<lang>_INCLUDE_PATH MPI_<lang>_LINK_FLAGS MPI_<lang>_FOUND
# MPI_<lang>_COMPILE_FLAGS MPI_<lang>_LIBRARIES
#
# MPI_<lang>_COMPILER must be set beforehand to the absolute path to an MPI compiler for
# <lang>. Additionally, MPI_<lang>_INCLUDE_PATH and MPI_<lang>_LIBRARIES may be set
# to skip autodetection.
#
# If try_libs is TRUE, this will also attempt to find plain MPI libraries in the usual
# way. In general, this is not as effective as interrogating the compilers, as it
# ignores language-specific flags and libraries. However, some MPI implementations
# (Windows implementations) do not have compiler wrappers, so this approach must be used.
#
function (interrogate_mpi_compiler lang try_libs)
# MPI_${lang}_NO_INTERROGATE will be set to a compiler name when the *regular* compiler was
# discovered to be the MPI compiler. This happens on machines like the Cray XE6 that use
# modules to set cc, CC, and ftn to the MPI compilers. If the user force-sets another MPI
# compiler, MPI_${lang}_COMPILER won't be equal to MPI_${lang}_NO_INTERROGATE, and we'll
# inspect that compiler anew. This allows users to set new compilers w/o rm'ing cache.
string(COMPARE NOTEQUAL "${MPI_${lang}_NO_INTERROGATE}" "${MPI_${lang}_COMPILER}" interrogate)
# If MPI is set already in the cache, don't bother with interrogating the compiler.
if (interrogate AND ((NOT MPI_${lang}_INCLUDE_PATH) OR (NOT MPI_${lang}_LIBRARIES)))
if (MPI_${lang}_COMPILER)
# Check whether the -showme:compile option works. This indicates that we have either OpenMPI
# or a newer version of LAM-MPI, and implies that -showme:link will also work.
_mpi_check_compiler("${MPI_${lang}_COMPILER}" "-showme:compile" MPI_COMPILE_CMDLINE MPI_COMPILER_RETURN)
if (MPI_COMPILER_RETURN EQUAL 0)
# If we appear to have -showme:compile, then we should
# also have -showme:link. Try it.
execute_process(
COMMAND ${MPI_${lang}_COMPILER} -showme:link
OUTPUT_VARIABLE MPI_LINK_CMDLINE OUTPUT_STRIP_TRAILING_WHITESPACE
ERROR_VARIABLE MPI_LINK_CMDLINE ERROR_STRIP_TRAILING_WHITESPACE
RESULT_VARIABLE MPI_COMPILER_RETURN)
if (MPI_COMPILER_RETURN EQUAL 0)
# We probably have -showme:incdirs and -showme:libdirs as well,
# so grab that while we're at it.
execute_process(
COMMAND ${MPI_${lang}_COMPILER} -showme:incdirs
OUTPUT_VARIABLE MPI_INCDIRS OUTPUT_STRIP_TRAILING_WHITESPACE
ERROR_VARIABLE MPI_INCDIRS ERROR_STRIP_TRAILING_WHITESPACE)
execute_process(
COMMAND ${MPI_${lang}_COMPILER} -showme:libdirs
OUTPUT_VARIABLE MPI_LIBDIRS OUTPUT_STRIP_TRAILING_WHITESPACE
ERROR_VARIABLE MPI_LIBDIRS ERROR_STRIP_TRAILING_WHITESPACE)
else()
# reset things here if something went wrong.
set(MPI_COMPILE_CMDLINE)
set(MPI_LINK_CMDLINE)
endif()
endif ()
# Older versions of LAM-MPI have "-showme". Try to find that.
if (NOT MPI_COMPILER_RETURN EQUAL 0)
_mpi_check_compiler("${MPI_${lang}_COMPILER}" "-showme" MPI_COMPILE_CMDLINE MPI_COMPILER_RETURN)
endif()
# MVAPICH uses -compile-info and -link-info. Try them.
if (NOT MPI_COMPILER_RETURN EQUAL 0)
_mpi_check_compiler("${MPI_${lang}_COMPILER}" "-compile-info" MPI_COMPILE_CMDLINE MPI_COMPILER_RETURN)
# If we have compile-info, also have link-info.
if (MPI_COMPILER_RETURN EQUAL 0)
execute_process(
COMMAND ${MPI_${lang}_COMPILER} -link-info
OUTPUT_VARIABLE MPI_LINK_CMDLINE OUTPUT_STRIP_TRAILING_WHITESPACE
ERROR_VARIABLE MPI_LINK_CMDLINE ERROR_STRIP_TRAILING_WHITESPACE
RESULT_VARIABLE MPI_COMPILER_RETURN)
endif()
# make sure we got compile and link. Reset vars if something's wrong.
if (NOT MPI_COMPILER_RETURN EQUAL 0)
set(MPI_COMPILE_CMDLINE)
set(MPI_LINK_CMDLINE)
endif()
endif()
# MPICH just uses "-show". Try it.
if (NOT MPI_COMPILER_RETURN EQUAL 0)
_mpi_check_compiler("${MPI_${lang}_COMPILER}" "-show" MPI_COMPILE_CMDLINE MPI_COMPILER_RETURN)
endif()
if (MPI_COMPILER_RETURN EQUAL 0)
# We have our command lines, but we might need to copy MPI_COMPILE_CMDLINE
# into MPI_LINK_CMDLINE, if we didn't find the link line.
if (NOT MPI_LINK_CMDLINE)
set(MPI_LINK_CMDLINE ${MPI_COMPILE_CMDLINE})
endif()
else()
message(STATUS "Unable to determine MPI from MPI driver ${MPI_${lang}_COMPILER}")
set(MPI_COMPILE_CMDLINE)
set(MPI_LINK_CMDLINE)
endif()
# Here, we're done with the interrogation part, and we'll try to extract args we care
# about from what we learned from the compiler wrapper scripts.
# If interrogation came back with something, extract our variable from the MPI command line
if (MPI_COMPILE_CMDLINE OR MPI_LINK_CMDLINE)
# Extract compile flags from the compile command line.
string(REGEX MATCHALL "(^| )-[Df]([^\" ]+|\"[^\"]+\")" MPI_ALL_COMPILE_FLAGS "${MPI_COMPILE_CMDLINE}")
set(MPI_COMPILE_FLAGS_WORK)
foreach(FLAG ${MPI_ALL_COMPILE_FLAGS})
if (MPI_COMPILE_FLAGS_WORK)
set(MPI_COMPILE_FLAGS_WORK "${MPI_COMPILE_FLAGS_WORK} ${FLAG}")
else()
set(MPI_COMPILE_FLAGS_WORK ${FLAG})
endif()
endforeach()
# Extract include paths from compile command line
string(REGEX MATCHALL "(^| )-I([^\" ]+|\"[^\"]+\")" MPI_ALL_INCLUDE_PATHS "${MPI_COMPILE_CMDLINE}")
foreach(IPATH ${MPI_ALL_INCLUDE_PATHS})
string(REGEX REPLACE "^ ?-I" "" IPATH ${IPATH})
string(REPLACE "//" "/" IPATH ${IPATH})
list(APPEND MPI_INCLUDE_PATH_WORK ${IPATH})
endforeach()
# try using showme:incdirs if extracting didn't work.
if (NOT MPI_INCLUDE_PATH_WORK)
set(MPI_INCLUDE_PATH_WORK ${MPI_INCDIRS})
separate_arguments(MPI_INCLUDE_PATH_WORK)
endif()
# If all else fails, just search for mpi.h in the normal include paths.
if (NOT MPI_INCLUDE_PATH_WORK)
set(MPI_HEADER_PATH "MPI_HEADER_PATH-NOTFOUND" CACHE FILEPATH "Cleared" FORCE)
find_path(MPI_HEADER_PATH mpi.h
HINTS ${_MPI_BASE_DIR} ${_MPI_PREFIX_PATH}
PATH_SUFFIXES include)
set(MPI_INCLUDE_PATH_WORK ${MPI_HEADER_PATH})
endif()
# Extract linker paths from the link command line
string(REGEX MATCHALL "(^| |-Wl,)-L([^\" ]+|\"[^\"]+\")" MPI_ALL_LINK_PATHS "${MPI_LINK_CMDLINE}")
set(MPI_LINK_PATH)
foreach(LPATH ${MPI_ALL_LINK_PATHS})
string(REGEX REPLACE "^(| |-Wl,)-L" "" LPATH ${LPATH})
string(REPLACE "//" "/" LPATH ${LPATH})
list(APPEND MPI_LINK_PATH ${LPATH})
endforeach()
# try using showme:libdirs if extracting didn't work.
if (NOT MPI_LINK_PATH)
set(MPI_LINK_PATH ${MPI_LIBDIRS})
separate_arguments(MPI_LINK_PATH)
endif()
# Extract linker flags from the link command line
string(REGEX MATCHALL "(^| )(-Wl,|-Xlinker )([^\" ]+|\"[^\"]+\")" MPI_ALL_LINK_FLAGS "${MPI_LINK_CMDLINE}")
set(MPI_LINK_FLAGS_WORK)
foreach(FLAG ${MPI_ALL_LINK_FLAGS})
if (MPI_LINK_FLAGS_WORK)
set(MPI_LINK_FLAGS_WORK "${MPI_LINK_FLAGS_WORK} ${FLAG}")
else()
set(MPI_LINK_FLAGS_WORK ${FLAG})
endif()
endforeach()
# Extract the set of libraries to link against from the link command
# line
string(REGEX MATCHALL "(^| )-l([^\" ]+|\"[^\"]+\")" MPI_LIBNAMES "${MPI_LINK_CMDLINE}")
# add the compiler implicit directories because some compilers
# such as the intel compiler have libraries that show up
# in the showme list that can only be found in the implicit
# link directories of the compiler.
if (DEFINED CMAKE_${lang}_IMPLICIT_LINK_DIRECTORIES)
set(MPI_LINK_PATH
"${MPI_LINK_PATH};${CMAKE_${lang}_IMPLICIT_LINK_DIRECTORIES}")
endif ()
# Determine full path names for all of the libraries that one needs
# to link against in an MPI program
foreach(LIB ${MPI_LIBNAMES})
string(REGEX REPLACE "^ ?-l" "" LIB ${LIB})
# MPI_LIB is cached by find_library, but we don't want that. Clear it first.
set(MPI_LIB "MPI_LIB-NOTFOUND" CACHE FILEPATH "Cleared" FORCE)
find_library(MPI_LIB NAMES ${LIB} HINTS ${MPI_LINK_PATH})
if (MPI_LIB)
list(APPEND MPI_LIBRARIES_WORK ${MPI_LIB})
elseif (NOT MPI_FIND_QUIETLY)
message(WARNING "Unable to find MPI library ${LIB}")
endif()
endforeach()
# Sanity check MPI_LIBRARIES to make sure there are enough libraries
list(LENGTH MPI_LIBRARIES_WORK MPI_NUMLIBS)
list(LENGTH MPI_LIBNAMES MPI_NUMLIBS_EXPECTED)
if (NOT MPI_NUMLIBS EQUAL MPI_NUMLIBS_EXPECTED)
set(MPI_LIBRARIES_WORK "MPI_${lang}_LIBRARIES-NOTFOUND")
endif()
endif()
elseif(try_libs)
# If we didn't have an MPI compiler script to interrogate, attempt to find everything
# with plain old find functions. This is nasty because MPI implementations have LOTS of
# different library names, so this section isn't going to be very generic. We need to
# make sure it works for MS MPI, though, since there are no compiler wrappers for that.
find_path(MPI_HEADER_PATH mpi.h
HINTS ${_MPI_BASE_DIR} ${_MPI_PREFIX_PATH}
PATH_SUFFIXES include Inc)
set(MPI_INCLUDE_PATH_WORK ${MPI_HEADER_PATH})
# Decide between 32-bit and 64-bit libraries for Microsoft's MPI
if("${CMAKE_SIZEOF_VOID_P}" EQUAL 8)
set(MS_MPI_ARCH_DIR x64)
set(MS_MPI_ARCH_DIR2 amd64)
else()
set(MS_MPI_ARCH_DIR x86)
set(MS_MPI_ARCH_DIR2 i386)
endif()
set(MPI_LIB "MPI_LIB-NOTFOUND" CACHE FILEPATH "Cleared" FORCE)
find_library(MPI_LIB
NAMES mpi mpich mpich2 msmpi
HINTS ${_MPI_BASE_DIR} ${_MPI_PREFIX_PATH}
PATH_SUFFIXES lib lib/${MS_MPI_ARCH_DIR} Lib Lib/${MS_MPI_ARCH_DIR} Lib/${MS_MPI_ARCH_DIR2})
set(MPI_LIBRARIES_WORK ${MPI_LIB})
# Right now, we only know about the extra libs for C++.
# We could add Fortran here (as there is usually libfmpich, etc.), but
# this really only has to work with MS MPI on Windows.
# Assume that other MPI's are covered by the compiler wrappers.
if (${lang} STREQUAL CXX)
set(MPI_LIB "MPI_LIB-NOTFOUND" CACHE FILEPATH "Cleared" FORCE)
find_library(MPI_LIB
NAMES mpi++ mpicxx cxx mpi_cxx
HINTS ${_MPI_BASE_DIR} ${_MPI_PREFIX_PATH}
PATH_SUFFIXES lib)
if (MPI_LIBRARIES_WORK AND MPI_LIB)
list(APPEND MPI_LIBRARIES_WORK ${MPI_LIB})
endif()
endif()
if (NOT MPI_LIBRARIES_WORK)
set(MPI_LIBRARIES_WORK "MPI_${lang}_LIBRARIES-NOTFOUND")
endif()
endif()
# If we found MPI, set up all of the appropriate cache entries
set(MPI_${lang}_COMPILE_FLAGS ${MPI_COMPILE_FLAGS_WORK} CACHE STRING "MPI ${lang} compilation flags" FORCE)
set(MPI_${lang}_INCLUDE_PATH ${MPI_INCLUDE_PATH_WORK} CACHE STRING "MPI ${lang} include path" FORCE)
set(MPI_${lang}_LINK_FLAGS ${MPI_LINK_FLAGS_WORK} CACHE STRING "MPI ${lang} linking flags" FORCE)
set(MPI_${lang}_LIBRARIES ${MPI_LIBRARIES_WORK} CACHE STRING "MPI ${lang} libraries to link against" FORCE)
mark_as_advanced(MPI_${lang}_COMPILE_FLAGS MPI_${lang}_INCLUDE_PATH MPI_${lang}_LINK_FLAGS MPI_${lang}_LIBRARIES)
# clear out our temporary lib/header detectionv variable here.
set(MPI_LIB "MPI_LIB-NOTFOUND" CACHE INTERNAL "Scratch variable for MPI lib detection" FORCE)
set(MPI_HEADER_PATH "MPI_HEADER_PATH-NOTFOUND" CACHE INTERNAL "Scratch variable for MPI header detection" FORCE)
endif()
# finally set a found variable for each MPI language
if (MPI_${lang}_INCLUDE_PATH AND MPI_${lang}_LIBRARIES)
set(MPI_${lang}_FOUND TRUE PARENT_SCOPE)
else()
set(MPI_${lang}_FOUND FALSE PARENT_SCOPE)
endif()
endfunction()
# This function attempts to compile with the regular compiler, to see if MPI programs
# work with it. This is a last ditch attempt after we've tried interrogating mpicc and
# friends, and after we've tried to find generic libraries. Works on machines like
# Cray XE6, where the modules environment changes what MPI version cc, CC, and ftn use.
function(try_regular_compiler lang success)
set(scratch_directory ${CMAKE_CURRENT_BINARY_DIR}${CMAKE_FILES_DIRECTORY})
if (${lang} STREQUAL Fortran)
set(test_file ${scratch_directory}/cmake_mpi_test.f90)
file(WRITE ${test_file}
"program hello\n"
"include 'mpif.h'\n"
"integer ierror\n"
"call MPI_INIT(ierror)\n"
"call MPI_FINALIZE(ierror)\n"
"end\n")
else()
if (${lang} STREQUAL CXX)
set(test_file ${scratch_directory}/cmake_mpi_test.cpp)
else()
set(test_file ${scratch_directory}/cmake_mpi_test.c)
endif()
file(WRITE ${test_file}
"#include <mpi.h>\n"
"int main(int argc, char **argv) {\n"
" MPI_Init(&argc, &argv);\n"
" MPI_Finalize();\n"
"}\n")
endif()
try_compile(compiler_has_mpi ${scratch_directory} ${test_file})
if (compiler_has_mpi)
set(MPI_${lang}_NO_INTERROGATE ${CMAKE_${lang}_COMPILER} CACHE STRING "Whether to interrogate MPI ${lang} compiler" FORCE)
set(MPI_${lang}_COMPILER ${CMAKE_${lang}_COMPILER} CACHE STRING "MPI ${lang} compiler" FORCE)
set(MPI_${lang}_COMPILE_FLAGS "" CACHE STRING "MPI ${lang} compilation flags" FORCE)
set(MPI_${lang}_INCLUDE_PATH "" CACHE STRING "MPI ${lang} include path" FORCE)
set(MPI_${lang}_LINK_FLAGS "" CACHE STRING "MPI ${lang} linking flags" FORCE)
set(MPI_${lang}_LIBRARIES "" CACHE STRING "MPI ${lang} libraries to link against" FORCE)
endif()
set(${success} ${compiler_has_mpi} PARENT_SCOPE)
unset(compiler_has_mpi CACHE)
endfunction()
# End definitions, commence real work here.
# Most mpi distros have some form of mpiexec which gives us something we can reliably look for.
find_program(MPIEXEC
NAMES ${_MPI_EXEC_NAMES}
HINTS ${MPI_HOME} $ENV{MPI_HOME}
PATHS ${_MPI_PREFIX_PATH}
PATH_SUFFIXES bin
DOC "Executable for running MPI programs.")
# call get_filename_component twice to remove mpiexec and the directory it exists in (typically bin).
# This gives us a fairly reliable base directory to search for /bin /lib and /include from.
get_filename_component(_MPI_BASE_DIR "${MPIEXEC}" PATH)
get_filename_component(_MPI_BASE_DIR "${_MPI_BASE_DIR}" PATH)
set(MPIEXEC_NUMPROC_FLAG "-np" CACHE STRING "Flag used by MPI to specify the number of processes for MPIEXEC; the next option will be the number of processes.")
set(MPIEXEC_PREFLAGS "" CACHE STRING "These flags will be directly before the executable that is being run by MPIEXEC.")
set(MPIEXEC_POSTFLAGS "" CACHE STRING "These flags will come after all flags given to MPIEXEC.")
set(MPIEXEC_MAX_NUMPROCS "2" CACHE STRING "Maximum number of processors available to run MPI applications.")
mark_as_advanced(MPIEXEC MPIEXEC_NUMPROC_FLAG MPIEXEC_PREFLAGS MPIEXEC_POSTFLAGS MPIEXEC_MAX_NUMPROCS)
#=============================================================================
# Backward compatibility input hacks. Propagate the FindMPI hints to C and
# CXX if the respective new versions are not defined. Translate the old
# MPI_LIBRARY and MPI_EXTRA_LIBRARY to respective MPI_${lang}_LIBRARIES.
#
# Once we find the new variables, we translate them back into their old
# equivalents below.
foreach (lang C CXX)
# Old input variables.
set(_MPI_OLD_INPUT_VARS COMPILER COMPILE_FLAGS INCLUDE_PATH LINK_FLAGS)
# Set new vars based on their old equivalents, if the new versions are not already set.
foreach (var ${_MPI_OLD_INPUT_VARS})
if (NOT MPI_${lang}_${var} AND MPI_${var})
set(MPI_${lang}_${var} "${MPI_${var}}")
endif()
endforeach()
# Special handling for MPI_LIBRARY and MPI_EXTRA_LIBRARY, which we nixed in the
# new FindMPI. These need to be merged into MPI_<lang>_LIBRARIES
if (NOT MPI_${lang}_LIBRARIES AND (MPI_LIBRARY OR MPI_EXTRA_LIBRARY))
set(MPI_${lang}_LIBRARIES ${MPI_LIBRARY} ${MPI_EXTRA_LIBRARY})
endif()
endforeach()
#=============================================================================
# This loop finds the compilers and sends them off for interrogation.
foreach (lang C CXX Fortran)
if (CMAKE_${lang}_COMPILER_WORKS)
# If the user supplies a compiler *name* instead of an absolute path, assume that we need to find THAT compiler.
if (MPI_${lang}_COMPILER)
if (NOT IS_ABSOLUTE "${MPI_${lang}_COMPILER}")
# Get rid of our default list of names and just search for the name the user wants.
set(_MPI_${lang}_COMPILER_NAMES ${MPI_${lang}_COMPILER})
set(MPI_${lang}_COMPILER "MPI_${lang}_COMPILER-NOTFOUND" CACHE FILEPATH "Cleared" FORCE)
endif()
# If the user specifies a compiler, we don't want to try to search libraries either.
set(try_libs FALSE)
else()
set(try_libs TRUE)
endif()
find_program(MPI_${lang}_COMPILER
NAMES ${_MPI_${lang}_COMPILER_NAMES}
HINTS ${_MPI_BASE_DIR}/bin
PATHS ${_MPI_PREFIX_PATH}
)
interrogate_mpi_compiler(${lang} ${try_libs})
mark_as_advanced(MPI_${lang}_COMPILER)
# last ditch try -- if nothing works so far, just try running the regular compiler and
# see if we can create an MPI executable.
set(regular_compiler_worked 0)
if (NOT MPI_${lang}_LIBRARIES OR NOT MPI_${lang}_INCLUDE_PATH)
try_regular_compiler(${lang} regular_compiler_worked)
endif()
set(MPI_${lang}_FIND_QUIETLY ${MPI_FIND_QUIETLY})
set(MPI_${lang}_FIND_REQUIRED ${MPI_FIND_REQUIRED})
set(MPI_${lang}_FIND_VERSION ${MPI_FIND_VERSION})
set(MPI_${lang}_FIND_VERSION_EXACT ${MPI_FIND_VERSION_EXACT})
if (regular_compiler_worked)
find_package_handle_standard_args(MPI_${lang} DEFAULT_MSG MPI_${lang}_COMPILER)
else()
find_package_handle_standard_args(MPI_${lang} DEFAULT_MSG MPI_${lang}_LIBRARIES MPI_${lang}_INCLUDE_PATH)
endif()
endif()
endforeach()
#=============================================================================
# More backward compatibility stuff
#
# Bare MPI sans ${lang} vars are set to CXX then C, depending on what was found.
# This mimics the behavior of the old language-oblivious FindMPI.
set(_MPI_OLD_VARS FOUND COMPILER INCLUDE_PATH COMPILE_FLAGS LINK_FLAGS LIBRARIES)
if (MPI_CXX_FOUND)
foreach (var ${_MPI_OLD_VARS})
set(MPI_${var} ${MPI_CXX_${var}})
endforeach()
elseif (MPI_C_FOUND)
foreach (var ${_MPI_OLD_VARS})
set(MPI_${var} ${MPI_C_${var}})
endforeach()
else()
# Note that we might still have found Fortran, but you'll need to use MPI_Fortran_FOUND
set(MPI_FOUND FALSE)
endif()
# Chop MPI_LIBRARIES into the old-style MPI_LIBRARY and MPI_EXTRA_LIBRARY, and set them in cache.
if (MPI_LIBRARIES)
list(GET MPI_LIBRARIES 0 MPI_LIBRARY_WORK)
set(MPI_LIBRARY ${MPI_LIBRARY_WORK} CACHE FILEPATH "MPI library to link against" FORCE)
else()
set(MPI_LIBRARY "MPI_LIBRARY-NOTFOUND" CACHE FILEPATH "MPI library to link against" FORCE)
endif()
list(LENGTH MPI_LIBRARIES MPI_NUMLIBS)
if (MPI_NUMLIBS GREATER 1)
set(MPI_EXTRA_LIBRARY_WORK ${MPI_LIBRARIES})
list(REMOVE_AT MPI_EXTRA_LIBRARY_WORK 0)
set(MPI_EXTRA_LIBRARY ${MPI_EXTRA_LIBRARY_WORK} CACHE STRING "Extra MPI libraries to link against" FORCE)
else()
set(MPI_EXTRA_LIBRARY "MPI_EXTRA_LIBRARY-NOTFOUND" CACHE STRING "Extra MPI libraries to link against" FORCE)
endif()
#=============================================================================
# unset these vars to cleanup namespace
unset(_MPI_OLD_VARS)
unset(_MPI_PREFIX_PATH)
unset(_MPI_BASE_DIR)
foreach (lang C CXX Fortran)
unset(_MPI_${lang}_COMPILER_NAMES)
endforeach()