NAME
mpicxx - Compiles and links MPI programs written in C++
DESCRIPTION
This command can be used to compile and link MPI programs written in
C++. It provides the options and any special libraries that are needed
to compile and link MPI programs.
It is important to use this command, particularly when linking
programs, as it provides the necessary libraries.
COMMAND LINE ARGUMENTS
-show - Show the commands that would be used without runnning them
-help - Give short help
-cxx=name
- Use compiler name instead of the default choice. Use this
only if the compiler is compatible with the MPICH library (see
below)
-config=name
- Load a configuration file for a particular compiler. This
allows a single mpicxx command to be used with multiple
compilers.
-compile_info
- Show the steps for compiling a program. This option can be
used to see what options and include paths are used by mpicxx.
-link_info
- Show the steps for linking a program. This optoin can be used
to see what options and libraries are used by mpicxx.
-profile=name
- Use the MPI profiling given by name. See below for details
-mpe=name
- Use an MPE profiling library. The behavior is similar to
using -profile=mpe_name.conf .
-echo - Show exactly what this program is doing. This option should
normally not be used.
others - are passed to the compiler or linker. For example, -c causes
files to be compiled, -g selects compilation with debugging on
most systems, and -o name causes linking with the output
executable given the name name .
ENVIRONMENT VARIABLES
The environment variables MPICH_CXX may be used to select different C++
compiler and linker. Note that since MPICH is built with a particular
C and Fortran compiler, changing the compilers used can cause problems.
Use this only if you could intermix code compiled with the different
compilers.
The environment variable MPICC_PROFILE specifies a profile library and
has the same effect as if -profile=$MPICC_PROFILE were used as an
argument to mpicc . See the discussion of -profile below for more
details.
COMPATIBLE COMPILERS
The MPI library may be used with any compiler that uses the same
lengths for basic data objects (such as long double ) and that uses
compatible run-time libraries. On many systems, the various compilers
are compatible and may be used interchangably. There are exceptions;
if you use the MPICH_CXX environment variable or the -cxx=name command-
line argument to override the choice of compiler and encounter
problems, try reconfiguring MPICH2 with the new compiler, and
installing MPICH2 in a separate location. See the installation manual
for more details.
EXAMPLES
To compile a single file foo.c , use
mpicxx -c foo.cxx
To link the output and make an executable, use
mpicxx -o foo foo.o
Combining compilation and linking in a single command
mpicxx -o foo foo.cxx
is a convenient way to build simple programs.
SELECTING A PROFILING LIBRARY
The -profile=name argument allows you to specify an MPI profiling
library to be used. name can have two forms:
A library in the same directory as the MPI library
The name of a profile configuration file
If name is a library, then this library is included before the MPI
library. This allows the simple use of libraries that make use of the
MPI profiling interface and that are installed in the same directory as
the MPI library.
If name.conf is the name of a file in the sysconfdir directory, then
this is read and may define the following variables:
PROFILE_PRELIB
- Libraries (and paths) to include before the MPI library
PROFILE_POSTLIB
- Libraries to include after the MPI library
PROFILE_INCPATHS
- C preprocessor arguments for any include files For example, to
add /usr/local/myprof/include to the include path and the
library libmyprof.a in /usr/local/myprof/lib to the link step,
you could create the file myprof.conf with the lines
PROFILE_PRELIB="-L/usr/local/myprof/lib -lmyprof"
PROFILE_INCPATHS="-I/usr/local/myprof/include"
and place it in the sysconfdir directory (this directory is set
at configure time when MPICH is built). Then using the command-
line argument -profile=myprof will cause these definitions to be
added to the relevant compile commands.
SEE ALSO
mpif77, mpicc, mpif90, mpiexec
LOCATION
mpicxx.txt
11/2/2007 mpicxx(1)