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The problem was that we had several variables in Fortran common blocks
of various types, but their C counterparts were all of a type
equivalent to a fortran double complex. This didn't seem to matter
for the compilers that we tested, but we never tested static builds
(which is where this problem seems to occur, at least with the Intel
compiler: the linker compilains that the variable in the common block
in the user's .o file was of one size/alignment but the one in the C
library was a different size/alignment).
So this patch fixes the sizes/types of the Fortran common block
variables and their corresponding C instantiations to be of the same
sizes/types.
But wait, there's more.
We recently introduced a fix for the OSX linker where some C versions
of the fortran common block variables (e.g.,
_ompi_fortran_status_ignore) were not being found when linking
ompi_info (!). Further research shows that the code path for
ompi_info to require ompi_fortran_status_ignore is, unfortunately,
necessary (a quirk of how various components pull in different
portions of the code base -- nothing in ompi_info itself requires
fortran or MPI knowledge, of course).
Hence, the real problem was that there was no code path from ompi_info
to the portion of the code base where the C globals corresponding to
the Fortran common block variables were instantiated. This is because
the OSX linker does not automatically pull in .o files that only
contain unintialized global variables; the OSX linker typically only
pulls in a .o file from a library if it either has a function that is
used or have a global variable that is initialized (that's the short
version; lots of details and corner cases omitted). Hence, we changed
the global C variables corresponding to the fortran common blocks to
be initialized, thereby causing the OSX linker to pull them in
automatically -- problem solved. At the same time, we moved the
constants to another .c file with a function, just for good measure.
However, this didn't really solve the problem:
1. The function in the file with the C versions of the fortran common
block variables (ompi/mpi/f77/test_constants_f.c) did not have a
code path that was reachable from ompi_info, so the only reason
that the constants were found (on OSX) was because they were
initialized in the global scope (i.e., causing the OSX compiler to
pull in that .o file).
2. Initializing these variable in the global scope causes problems for
some linkers where -- once all the size/type problems mentioned
above were fixed -- the alignments of fortran common blocks and C
global variables do not match (even though the types of the Fortran
and C variables match -- wow!). Hence, initializing the C
variables would not necessarily match the alignment of what Fortran
expected, and the linker would issue a warning (i.e., the alignment
warnings referenced in the original post).
The solution is two-fold:
1. Move the Fortran variables from test_constants_f.c to
ompi/mpi/runtime/ompi_mpi_init.c where there are other global
constants that *are* initialized (that had nothing to do with
fortran, so the alignment issues described above are not a factor),
and therefore all linkers (including the OSX linker) will pull in
this .o file and find all the symbols that it needs.
2. Do not initialize the C variables corresponding to the Fortran
common blocks in the global scope. Indeed, never initialize them
at all (because we never need their *values* - we only check for
their *locations*). Since nothing is ever written to these
variables (particularly in the global scope), the linker does not
see any alignment differences during initialization, but does make
both the C and Fortran variables have the same addresses (this
method has been working in LAM/MPI for over a decade).
There were some comments here in the OMPI code base and in the LAM
code base that stated/implied that C variables corresponding to
Fortran common blocks had to have the same alignment as the Fortran
common blocks (i.e., 16). There were attempts in both code bases to
ensure that this was true. However, the attempts were wrong (in both
code bases), and I have now read enough Fortran compiler documentation
to convince myself that matching alignments is not required (indeed,
it's beyond our control). As long as C variables corresponding to
Fortran common blocks are not initialized in the global scope, the
linker will "figure it out" and adjust the alignment to whatever is
required (i.e., the greater of the alignments). Specifically (to
counter comments that no longer exist in the OMPI code base but still
exist in the LAM code base):
- there is no need to make attempts to specially align C variables
corresponding to Fortran common blocks
- the types and sizes of C variables corresponding to Fortran common
blocks should match, but do not need to be on any particular
alignment
Finally, as a side effect of this effort, I found a bunch of
inconsistencies with the intent of status/array_of_statuses
parameters. For all the functions that I modified they should be
"out" (not inout).
This commit was SVN r11057.
- ensure to initialize the values that we use for fortran constants
(even tough their *values* don't matter -- only their *addresses* do,
but initializing them or not has implications for the OSX linker)
- move the fortran constants to a file with functions in it, because
the OSX linker sometimes does not import global variables from
object files that do not have functions (I'm not even going to
pretend to get all the subtle details about the OSX linker right
here -- it's just "better" to have global variables in object files
with functions that otherwise get pulled in during linker
resolution).
This commit was SVN r10908.
was that declaring the type of MPI_WTICK and MPI_TIME in mpif-common.h
would allow the F90 bindings to call through to the back end f77
function and have the right return type. But upon reflection, that's
silly -- we were just declaring the variables MPI_WTICK and MPI_WTIME
that were of type double precision. Duh.
So add some fixed (non-generated) wrapper F90 functions to call the
back-end *C* MPI_WTICK and MPI_TIME functions (vs. the back end *F77*
functions). We have to call the back-end C functions because there's
a name conflict if we try to call the back-end F77 functions -- for
the same reasons that we can't "implicitly" define MPI_WTIME and
MPI_WTICK in the f90 module, we can't call such an implicitly-defined
function. So we had to add new back-end C functions that are directly
callable from Fortran, the easiest implementation of which was to
provide 4 one-line functions for each (rather than muck around with
weak symbols).
This commit was SVN r10448.
svn merge -r 9453:9609 https://svn.open-mpi.org/svn/ompi/tmp/f90-stuff .
Several improvements over the current F90 MPI bindings:
- The capability to make 4 sizes of the F90 bindings:
- trivial: only the F90-specific MPI functions (sizeof and a few
others)
- small: (this is the default) all MPI functions that do not take
choice buffers
- medium: small + all MPI functions that take one choice buffer
(e.g., MPI_SEND)
- large: all MPI functions, but those that take 2 choice buffers
(e.g., MPI_GATHER) only allow both buffers to be of the same type
- Remove all non-standard MPI types (LOGICAL*x, CHARACTER*x)
- Remove use of selected_*_kind() and only use MPI-defined types
(INTEGER*x, etc.)
- Decrease complexity of the F90 configure and build system
This commit was SVN r9610.
fortran strings to c strings, else the name-publishing and name-lookup
and all subsequent calls (e.g. connect/accept) do not work with fortran.
This commit was SVN r9272.
of the string. Since it is relevant fix, however not affecting any other
part of the source code, should probably still go onto the 1.0 branch.
This commit was SVN r9214.
add an explicit test case that checks for them. It is necessary to
put this test function here because the OMPI_IS* macros are only
defined in this directory.
This commit was SVN r9195.
- move files out of toplevel include/ and etc/, moving it into the
sub-projects
- rather than including config headers with <project>/include,
have them as <project>
- require all headers to be included with a project prefix, with
the exception of the config headers ({opal,orte,ompi}_config.h
mpi.h, and mpif.h)
This commit was SVN r8985.
complete, but stable enough that it will have no impact on general development,
so into the trunk it goes. Changes in this commit include:
- Remove the --with option for disabling MPI-2 onesided support. It
complicated code, and has no real reason for existing
- add a framework osc (OneSided Communication) for encapsulating
all the MPI-2 onesided functionality
- Modify the MPI interface functions for the MPI-2 onesided chapter
to properly call the underlying framework and do the required
error checking
- Created an osc component pt2pt, which is layered over the BML/BTL
for communication (although it also uses the PML for long message
transfers). Currently, all support functions, all communication
functions (Put, Get, Accumulate), and the Fence synchronization
function are implemented. The PWSC active synchronization
functions and Lock/Unlock passive synchronization functions are
still not implemented
This commit was SVN r8836.
case of:
sizeof(MPI_Flogical) != sizeof (int)
and
Fortran value of .TRUE. != 1
as is often the case.
- Check in configure the value of .TRUE., the C-type coresponding to
logical and check, that fortran compiler does not do something strange
with arrays of logicals
- Convert all occurrences of logicals in the fortran wrappers, only
in case it is needed.
*Please note* Implementation of MPI_Cart_sub needed special treatment.
- Output these value in ompi_info -a
- Clean up the prototypes_mpi.h to just have a single definition and
thereby deleting the necessity for prototypes_pmpi.h
- configured, compiled and tested with F90-program, which uses
MPI_Cart_create and MPI_Cart_get:
linux ia32, gcc (no testing, as no f90)
linux ia32, gcc --disable-mpi-f77 --disable-mpi-f90 (had a bug there)
linux ia32, icc-8.1
linux opteron, gcc-3.3.5, pgcc, pathccx/pathf90 (tested just
pgi-compiler)
linux em64t, gcc, icc-8.1 (tested just icc)
This commit was SVN r8254.
argument is defined to be
integer (KIND=MPI_ADDRESS_KIND)
we have to map that to an MPI_Aint in the f->c interface, else the
typecast back from the C to the Fortran interface will be wrong as well.
The same holds (at least) for all other new MPI-2 datatype functions
which take a byte-displacement or an address as an argument.
This commit was SVN r8243.
one that does not return any value. There are 2 exceptions MPI_Wtick and MPI_Wtime.
For these 2 we can insert the bindings manually.
This commit was SVN r8016.
restoring the PMPI version. A variety of reasons for this:
- mpi.h was blinding using inline in a C header without the configrue mojo
properly set it, as mpi.h doesn't include ompi_config.h. This eventually
would have caused a borked build.
- mpi.h and mpif.h were never updated to not include PMPI_W{tick,time} as
a proper prototype
- The C++ and F90 bindings didn't do the right things when there was no
PMPI version of the C call, but profiling was enabled
- Since we only use gettimeofday, the function call overhead really doesn't
matter
This should probably go to the 1.0 branch
This commit was SVN r8014.
AM_INIT_AUTOMAKE, instead of the deprecated version.
* Work around dumbness in modern AC_INIT that requires the version
number to be set at autoconf time (instead of at configure time, as
it was before). Set the version number, minus the subversion r number,
at autoconf time. Override the internal variables to include the r
number (if needed) at configure time. Basically, the right thing
should always happen. The only place it might not is the version
reported as part of configure --help will not have an r number.
* Since AM_INIT_AUTOMAKE taks a list of options, no need to specify
them in all the Makefile.am files.
* Addes support for subdir-objects, meaning that object files are put
in the directory containing source files, even if the Makefile.am is
in another directory. This should start making it feasible to
reduce the number of Makefile.am files we have in the tree, which
will greatly reduce the time to run autogen and configure.
This commit was SVN r7211.
* rename ompi_basename to opal_basename
* rename ompi bitop functions to opal
* rename ompi_cmd_line to opal_cmd_line
* rename ompi_sizet2int to opal_sizet2int
* rename orte_daemon_init to opal_daemon_init
* rename ompi_few to opal_few
This commit was SVN r6330.
