QLogic OFED+ Host Software User Guide, Rev. B

F–Troubleshooting
QLogic MPI Troubleshooting
Compiling on Development Nodes
If the mpi-devel-* RPM is installed with the --prefix /path/to/devel
option, then mpicc, etc. must be passed in -I/path/to/devel/include for
the compiler to find the MPI include files, as in this example:
$ mpicc myprogram.c -I/path/to/devel/include
If you are using Fortran 90 or Fortran 95, a similar option is needed for the
compiler to find the module files:
$ mpif90 myprogramf90.f90 -I/path/to/devel/include
If the mpi-lib-* RPM is installed on these development nodes with the
--prefix /path/to/libs option, then the compiler needs the
-L/path/to/libs option so it can find the libraries. Here is the example for
mpicc:
$ mpicc myprogram.c -L/path/to/libs/lib (for 32 bit)
$ mpicc myprogram.c -L/path/to/libs/lib64 (for 64 bit)
To find both the include files and the libraries with these non-standard locations,
type:
$ mpicc myprogram.c -I/path/to/devel/include -L/path/to/libs/lib
Specifying the Run-time Library Path
There are several ways to specify the run-time library path so that when the
programs are run, the appropriate libraries are found in the new location. There
are three different ways to do this:
• Use the -Wl,-rpath, option when compiling on the development node.
• Update the /etc/ld.so.conf file on the compute nodes to include the path.
• Export the path in the .mpirunrc file.
These methods are explained in more detail in the following paragraphs.
An additional linker option, -Wl,-rpath, supplies the run-time library path when
compiling on the development node. The compiler options now look like this:
$ mpicc myprogram.c -I/path/to/devel/include -L/path/to/libs/lib
-Wl,-rpath,/path/to/libs/lib
The above compiler command ensures that the program will run using this path on
any machine.
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