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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.
cannot include the PMPI_WTIME|WTICK functions in the external and
double precision statements because some compilers complain about
this. Instead, we need to use the macro that is defined by
configure.ac (MPIF_H_PMPI_W_FUNCS). This unfortunately means that we
need to generate mpif.h (in addition to mpif-config.h) because the
"external" statement is toxic to F90 compilers.
This commit was SVN r10464.
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.
* Change the type of Fortan's MPI_STATUSES_IGNORE to double complex
so that it will never possibly be mistaken for a real status (i.e.,
integer(MPI_STATUS_SIZE)), particularly in the F90 bindings. See
comment in mpif-common.h explaining this (analogous argument to
MPI_ARGVS_NULL for MPI_COMM_SPAWN_MULTIPLE).
* Add second interfaces for the following functions that take a double
complex (i.e., MPI_STATUSES_IGNORE). This required adding the second
interface in mpi-f90-interfaces.h[.sh] and then generating new wrapper
functions to call the back-end F77 function for each of these four, so
we added 4 new files in ompi/mpi/f90/scripts/ and updated the various
Makefile.am's to match:
* MPI_TESTALL
* MPI_TESTSOME
* MPI_WAITALL
* MPI_WAITSOME
The XSL is now not in sync with the scripts. Although I suppose that
that is becoming less and less important (because it does not impact
the end user at all -- to be 100% explicit, no release should ever be
held up because the XSL is out of sync), but it will probably be
important when we go to fix the "large" interface; so it's still worth
fixing... for now...
This commit was SVN r10281.
- Make the F90 bindings compile and link properly with gfortran 4.0,
4.1, Intel 9.0, PGI 6.1, Sun (don't know version offhand -- the most
current as of this writing, I think), and NAG 5.2, although some
have limitations (e.g., NAG can't seem to handle the medium and
large sizes)
- Building the F90 "small" module size is now the default, even for
developers
- Split up mpif.h into multiple files because parts of it were toxic
to the F90 bindings
- Properly specify unsized/unshaped arrays to make the bindings work
on all known compilers
- Make ompi_info show Fortran 90 bindings size
- XML somewhat lags the generated scripts as of this commit, but
functionality was my main goal -- the XML can be updated later (if
at all).
This commit was SVN r10118.
- split mpif.h into mpif.h and mpif-common.h[.in]
- mpif-common.h is included by various f90 things and contains output
from configure
- mpif.h defines some f77-specific stuff and then includes
mpif-common.h
This commit was SVN r9997.
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.
* Don't do the .in -> .tmp -> header thing for the prefixes and versions.
It causes some severe cleanup issues all to save 4 files from rebuilding
when configure is run.
* Clean up some makefiles so it's clear what is being installed/disted
This commit was SVN r9260.
installation directories) in configure, the files that depend on this
information are not properly rebuilt. If you need this information,
don't setup a -D in the Makefile.am - instead, include
opal/install_dirs.h.
* Use the : option in AC_CONFIG_FILES to avoid needing to expose that
we are playing around with temporary files with our headers to avoid
rebuilding
* Clean up the version file information a bit, and like the install
directory stuff, make sure that there is a dependency so that
ompi_info gets rebuilt properly when a version number changes.
This commit was SVN r9256.
with MPI_WIN_NULL and the Fortran bindings.
It appears I had already done this, since all the infrastructure was already
in place. I probably edited mpi.h instead of mpi.h.in. Sigh.
This commit was SVN r9228.
they will match the prototypes in the [styictly-typed] MPI F90
bindings. Specifically, fix up MPI_COMM_SPAWN and
MPI_COMM_SPAWN_MULTIPLE so that the constants MPI_ARGV_NULL,
MPI_ERRCODES_IGNORE, and MPI_ARGVS_NULL can be used in the F90
bindings. Thanks to Michael Kluskens for pointing this out to us.
Some work still remains in the F90 bindings -- we are missing all
places where choice buffers can be of type CHARACTER.
This commit was SVN r9198.
- 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.
originally suggested by Ralf Wildenhues, to try to speed autogen, configure,
and make (and possibly even make install). Use automake's include directive
to drastically reduce the number of Makefile files (although the number of
Makefile.am files is the same - most are just included in a top-level
Makefile.am). Also use an Automake SUBDIRs feature to eliminate the
dynamic-mca tree, which was no longer really needed. This makes adding
a framework easier (since you don't have to remember the dynamic-mca
tree) and makes building faster (as make doesn't have to recurse through
the dynamic-mca tree)
This commit was SVN r7777.
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.
1. Added OMPI_PROC_ARCH as a defined registry key and added the code so that the architecture info gets properly transmitted across all processes using the startup message.
2. Added an OMPI_MODEX_KEY definition and removed the hard-coded "modex" key from pml_modex_exchange
This commit was SVN r7129.
OPAL_ERROR, same for all the other error codes. Also, make sure that there
are never conflicts between OPAL anr ORTE error codes (for example).
Finally, provide opal_perror(), opal_strerror(), and opal_strerror_r() to
give stringified error messages for the different error codes
This commit was SVN r6969.
1. Modify the registry to eliminate redundant data copying for startup messages.
2. Revise the subscription/trigger system to avoid redundant storage of triggers and subscriptions. This dramatically reduces the search time when a registry action occurs - to illustrate the point, there are now only a handful of triggers on the system for each job. Before, there were a handful of triggers for each PROCESS in the job, all of which had to be checked every time something happened on the registry. This is much, much faster now.
3. Update all subscriptions to the new format. There are now "named" subscriptions - this allows you to "name" a subscription that all the processes will be using. The first one to hit the registry actually defines the subscription. From then on, any subsequent "subscribes" to the same name just cause that process to "attach" to the existing subscription. This keeps the number of subscriptions being tracked by the registry to a minimum, while ensuring that each process still gets notified.
4. Do the same for triggers.
Also fixed a duplicate subscription problem that was causing people to receive data equal to the number of processes times the data they should have received from a trigger/subscription. Sorry about that... :-( ...but it's all better now!
Uncovered a situation where the modex data seems to be getting entered on the registry a second time - the latter time coming after the compound command has been "fired", thereby causing all the subscriptions to fire. Asked Tim and Jeff to look into this.
Second phase of the changes will involve modifying the xcast system so that the same message gets sent to all processes. This will further reduce the message traffic, and - once we have a true "broadcast" version of xcast - really speed things up and improve scalability.
This commit was SVN r6542.
