June 2012 - mpi-forum - mailman3.cels.anl.gov

Re: [Mpi-forum] C++ types inaccessible after #281
by Jeff Squyres 26 Jun '12

26 Jun '12

Yes, I think that Jed has a good point here. There are a few C++-specific datatypes for which it would be worth introducing new C datatypes (e.g., MPI_CXX_COMPLEX). It's too bad that no one realized this until now, because this won't make the MPI-3 deadline. But it could be part of MPI-3.1 or errata, or some such. Is there a C++ person out there who could draft a proposal about this? On Jun 26, 2012, at 1:02 AM, Jed Brown wrote: > I'm all for getting rid of the C++ bindings and see no compelling reason for anyone to use them. > > Predefined types are inconsequential to MPI-1 functionality, but they are special for one-sided, so availability of types is highly relevant to applications. This is a non-cosmetic change imposed by #281 that doesn't seem to have been discussed. > > On Jun 25, 2012 8:51 PM, "Fab Tillier" <ftillier(a)microsoft.com> wrote: > Ah, thanks, sorry for being dense (I'm not familiar with the C++ bindings as we don't ship them for MSMPI). > > Ticket 281 removes the entire C++ bindings from the standard, MPI::COMPLEX included. You'd need to convince your MPI library vendor to keep supplying you with an MPI-2.2 compliant version of the C++ bindings (which is still allowed by ticket #281). > > Hopefully someone with more experience with the C++ bindings can chime in, but I'd expect the answer to your original question is yes, ticket #281 intentionally removes all C++ support from MPI-3. > > -Fab > > Jed Brown wrote on Mon, 25 Jun 2012 at 21:31:55 > > > MPI::COMPLEX is not the same as MPI_C_COMPLEX (and the latter is not > > available on systems without C99). > > > On Jun 25, 2012 8:21 PM, "Fab Tillier" <ftillier(a)microsoft.com> wrote: > > Hi Jed, > > > > Maybe I'm not following you, but what predefined MPI datatype supports > > std::complex today? My understanding is that there is no support for > > std::complex in MPI today, and that ticket 281 does not change this at > > all. > > > > Thanks, > > -Fab > > > > Jed Brown wrote on Mon, 25 Jun 2012 at 20:42:53 > > > >> I see that std::complex will not be accessible in a predefined type if > >> #281 passes in its current form. Do you intend for there to be a > >> supported/recommended way for a C++ caller to get a complex predefined > >> (so that one-sided can be used) type? Note that C99 is not a subset of > >> any C++ and C99 complex cannot be used portably from C++ (even with > >> compiler suites that happen to support both). > >> > >> On Jun 25, 2012 7:07 PM, "Fab Tillier" <ftillier(a)microsoft.com > >> <mailto:[email protected]> > wrote: Hi Jed, > >> > >> Jed Brown wrote on Mon, 25 Jun 2012 at 16:43:54 > >> > >>> Is it intended that #281 would make std::complex inaccessible? Should > >>> there be a MPI_CXX_COMPLEX, MPI_CXX_DOUBLE_COMPLEX, > >>> MPI_CXX_LONG_DOUBLE_COMPLEX, and (possibly) MPI_CXX_BOOL? > >> > >> I don't think ticket #281 does anything with respect to std::complex > >> accessibility. The MPI standard defines the MPI_C_COMPLEX and family > >> as mapping to the C99 _Complex type (see Table 3.2, Predefined MPI > >> datatypes corresponding to C datatypes). The standard is clear that > >> there are no corresponding C++ bindings. > >> > >>> Note that C99 complex is not a substitute because Microsoft does not > >>> implement it and it has different semantics regarding numerical > >>> stability. (Well, C99 semantics are specified and useful, std::complex > >>> stability is not specified by any C++ standard and in practice, is not > >>> implemented in a stable way.) This is not such a big deal for use with > >>> collectives because user-defined MPI_Ops can be used, but only > >>> predefined types can be used with one-sided operations, so presence of > >>> complex datatypes (or lack thereof) is relevant to applications. > >> > >> The fact that Microsoft does not support C99 is lame. You can probably > >> get away using std::complex as a stand-in for C99 _Complex (but then > >> you're on your own), or move to a compiler that does (I believe the > >> Intel compiler supports C99 on Windows). > >> > >> -Fab > >> > > > _______________________________________________ > mpi-forum mailing list > mpi-forum(a)lists.mpi-forum.org > http://lists.mpi-forum.org/mailman/listinfo.cgi/mpi-forum -- Jeff Squyres jsquyres(a)cisco.com For corporate legal information go to: http://www.cisco.com/web/about/doing_business/legal/cri/

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Re: [Mpi-forum] C++ types inaccessible after #281
by Jeff Hammond 26 Jun '12

26 Jun '12

Maybe it makes sense to propose adding a C binding for a built-in datatype that supports C++. While the Forum clearly wants to kill C++ _bindings_, they insist that the C bindings are sufficient for C++, meaning that they still intend to support C++ as a language. There is no contradiction in adding support for C++ datatypes like std::complex while at the same time killing the C++ bindings. I think that they are separate issues and that there is a strong case to be made for adding an MPI datatype for C++ complex that works via the C bindings. Jeff On Tue, Jun 26, 2012 at 12:02 AM, Jed Brown <jedbrown(a)mcs.anl.gov> wrote: > I'm all for getting rid of the C++ bindings and see no compelling reason for > anyone to use them. > > Predefined types are inconsequential to MPI-1 functionality, but they are > special for one-sided, so availability of types is highly relevant to > applications. This is a non-cosmetic change imposed by #281 that doesn't > seem to have been discussed. > > On Jun 25, 2012 8:51 PM, "Fab Tillier" <ftillier(a)microsoft.com> wrote: >> >> Ah, thanks, sorry for being dense (I'm not familiar with the C++ bindings >> as we don't ship them for MSMPI). >> >> Ticket 281 removes the entire C++ bindings from the standard, MPI::COMPLEX >> included. ï¿½You'd need to convince your MPI library vendor to keep supplying >> you with an MPI-2.2 compliant version of the C++ bindings (which is still >> allowed by ticket #281). >> >> Hopefully someone with more experience with the C++ bindings can chime in, >> but I'd expect the answer to your original question is yes, ticket #281 >> intentionally removes all C++ support from MPI-3. >> >> -Fab >> >> Jed Brown wrote on Mon, 25 Jun 2012 at 21:31:55 >> >> > MPI::COMPLEX is not the same as MPI_C_COMPLEX (and the latter is not >> > available on systems without C99). >> >> > On Jun 25, 2012 8:21 PM, "Fab Tillier" <ftillier(a)microsoft.com> wrote: >> > Hi Jed, >> > >> > Maybe I'm not following you, but what predefined MPI datatype supports >> > std::complex today? ï¿½My understanding is that there is no support for >> > std::complex in MPI today, and that ticket 281 does not change this at >> > all. >> > >> > Thanks, >> > -Fab >> > >> > Jed Brown wrote on Mon, 25 Jun 2012 at 20:42:53 >> > >> >> I see that std::complex will not be accessible in a predefined type if >> >> #281 passes in its current form. Do you intend for there to be a >> >> supported/recommended way for a C++ caller to get a complex predefined >> >> (so that one-sided can be used) type? Note that C99 is not a subset of >> >> any C++ and C99 complex cannot be used portably from C++ (even with >> >> compiler suites that happen to support both). >> >> >> >> On Jun 25, 2012 7:07 PM, "Fab Tillier" <ftillier(a)microsoft.com >> >> <mailto:[email protected]> > wrote: Hi Jed, >> >> >> >> Jed Brown wrote on Mon, 25 Jun 2012 at 16:43:54 >> >> >> >>> Is it intended that #281 would make std::complex inaccessible? Should >> >>> there be a MPI_CXX_COMPLEX, MPI_CXX_DOUBLE_COMPLEX, >> >>> MPI_CXX_LONG_DOUBLE_COMPLEX, and (possibly) MPI_CXX_BOOL? >> >> >> >> I don't think ticket #281 does anything with respect to std::complex >> >> accessibility. ï¿½The MPI standard defines the MPI_C_COMPLEX and family >> >> as mapping to the C99 _Complex type (see Table 3.2, Predefined MPI >> >> datatypes corresponding to C datatypes). ï¿½The standard is clear that >> >> there are no corresponding C++ bindings. >> >> >> >>> Note that C99 complex is not a substitute because Microsoft does not >> >>> implement it and it has different semantics regarding numerical >> >>> stability. (Well, C99 semantics are specified and useful, std::complex >> >>> stability is not specified by any C++ standard and in practice, is not >> >>> implemented in a stable way.) This is not such a big deal for use with >> >>> collectives because user-defined MPI_Ops can be used, but only >> >>> predefined types can be used with one-sided operations, so presence of >> >>> complex datatypes (or lack thereof) is relevant to applications. >> >> >> >> The fact that Microsoft does not support C99 is lame. ï¿½You can probably >> >> get away using std::complex as a stand-in for C99 _Complex (but then >> >> you're on your own), or move to a compiler that does (I believe the >> >> Intel compiler supports C99 on Windows). >> >> >> >> -Fab >> >> >> > > > > _______________________________________________ > mpi-forum mailing list > mpi-forum(a)lists.mpi-forum.org > http://lists.mpi-forum.org/mailman/listinfo.cgi/mpi-forum -- Jeff Hammond Argonne Leadership Computing Facility University of Chicago Computation Institute jhammond(a)alcf.anl.gov / (630) 252-5381 http://www.linkedin.com/in/jeffhammond https://wiki.alcf.anl.gov/parts/index.php/User:Jhammond

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Re: [Mpi-forum] C++ types inaccessible after #281
by Jed Brown 26 Jun '12

26 Jun '12

I'm all for getting rid of the C++ bindings and see no compelling reason for anyone to use them. Predefined types are inconsequential to MPI-1 functionality, but they are special for one-sided, so availability of types is highly relevant to applications. This is a non-cosmetic change imposed by #281 that doesn't seem to have been discussed. On Jun 25, 2012 8:51 PM, "Fab Tillier" <ftillier(a)microsoft.com> wrote: > Ah, thanks, sorry for being dense (I'm not familiar with the C++ bindings > as we don't ship them for MSMPI). > > Ticket 281 removes the entire C++ bindings from the standard, MPI::COMPLEX > included. You'd need to convince your MPI library vendor to keep supplying > you with an MPI-2.2 compliant version of the C++ bindings (which is still > allowed by ticket #281). > > Hopefully someone with more experience with the C++ bindings can chime in, > but I'd expect the answer to your original question is yes, ticket #281 > intentionally removes all C++ support from MPI-3. > > -Fab > > Jed Brown wrote on Mon, 25 Jun 2012 at 21:31:55 > > > MPI::COMPLEX is not the same as MPI_C_COMPLEX (and the latter is not > > available on systems without C99). > > > On Jun 25, 2012 8:21 PM, "Fab Tillier" <ftillier(a)microsoft.com> wrote: > > Hi Jed, > > > > Maybe I'm not following you, but what predefined MPI datatype supports > > std::complex today? My understanding is that there is no support for > > std::complex in MPI today, and that ticket 281 does not change this at > > all. > > > > Thanks, > > -Fab > > > > Jed Brown wrote on Mon, 25 Jun 2012 at 20:42:53 > > > >> I see that std::complex will not be accessible in a predefined type if > >> #281 passes in its current form. Do you intend for there to be a > >> supported/recommended way for a C++ caller to get a complex predefined > >> (so that one-sided can be used) type? Note that C99 is not a subset of > >> any C++ and C99 complex cannot be used portably from C++ (even with > >> compiler suites that happen to support both). > >> > >> On Jun 25, 2012 7:07 PM, "Fab Tillier" <ftillier(a)microsoft.com > >> <mailto:[email protected]> > wrote: Hi Jed, > >> > >> Jed Brown wrote on Mon, 25 Jun 2012 at 16:43:54 > >> > >>> Is it intended that #281 would make std::complex inaccessible? Should > >>> there be a MPI_CXX_COMPLEX, MPI_CXX_DOUBLE_COMPLEX, > >>> MPI_CXX_LONG_DOUBLE_COMPLEX, and (possibly) MPI_CXX_BOOL? > >> > >> I don't think ticket #281 does anything with respect to std::complex > >> accessibility. The MPI standard defines the MPI_C_COMPLEX and family > >> as mapping to the C99 _Complex type (see Table 3.2, Predefined MPI > >> datatypes corresponding to C datatypes). The standard is clear that > >> there are no corresponding C++ bindings. > >> > >>> Note that C99 complex is not a substitute because Microsoft does not > >>> implement it and it has different semantics regarding numerical > >>> stability. (Well, C99 semantics are specified and useful, std::complex > >>> stability is not specified by any C++ standard and in practice, is not > >>> implemented in a stable way.) This is not such a big deal for use with > >>> collectives because user-defined MPI_Ops can be used, but only > >>> predefined types can be used with one-sided operations, so presence of > >>> complex datatypes (or lack thereof) is relevant to applications. > >> > >> The fact that Microsoft does not support C99 is lame. You can probably > >> get away using std::complex as a stand-in for C99 _Complex (but then > >> you're on your own), or move to a compiler that does (I believe the > >> Intel compiler supports C99 on Windows). > >> > >> -Fab > >> > > >

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Re: [Mpi-forum] C++ types inaccessible after #281
by Fab Tillier 25 Jun '12

25 Jun '12

Ah, thanks, sorry for being dense (I'm not familiar with the C++ bindings as we don't ship them for MSMPI). Ticket 281 removes the entire C++ bindings from the standard, MPI::COMPLEX included. You'd need to convince your MPI library vendor to keep supplying you with an MPI-2.2 compliant version of the C++ bindings (which is still allowed by ticket #281). Hopefully someone with more experience with the C++ bindings can chime in, but I'd expect the answer to your original question is yes, ticket #281 intentionally removes all C++ support from MPI-3. -Fab Jed Brown wrote on Mon, 25 Jun 2012 at 21:31:55 > MPI::COMPLEX is not the same as MPI_C_COMPLEX (and the latter is not > available on systems without C99). > On Jun 25, 2012 8:21 PM, "Fab Tillier" <ftillier(a)microsoft.com> wrote: > Hi Jed, > > Maybe I'm not following you, but what predefined MPI datatype supports > std::complex today? My understanding is that there is no support for > std::complex in MPI today, and that ticket 281 does not change this at > all. > > Thanks, > -Fab > > Jed Brown wrote on Mon, 25 Jun 2012 at 20:42:53 > >> I see that std::complex will not be accessible in a predefined type if >> #281 passes in its current form. Do you intend for there to be a >> supported/recommended way for a C++ caller to get a complex predefined >> (so that one-sided can be used) type? Note that C99 is not a subset of >> any C++ and C99 complex cannot be used portably from C++ (even with >> compiler suites that happen to support both). >> >> On Jun 25, 2012 7:07 PM, "Fab Tillier" <ftillier(a)microsoft.com >> <mailto:[email protected]> > wrote: Hi Jed, >> >> Jed Brown wrote on Mon, 25 Jun 2012 at 16:43:54 >> >>> Is it intended that #281 would make std::complex inaccessible? Should >>> there be a MPI_CXX_COMPLEX, MPI_CXX_DOUBLE_COMPLEX, >>> MPI_CXX_LONG_DOUBLE_COMPLEX, and (possibly) MPI_CXX_BOOL? >> >> I don't think ticket #281 does anything with respect to std::complex >> accessibility. The MPI standard defines the MPI_C_COMPLEX and family >> as mapping to the C99 _Complex type (see Table 3.2, Predefined MPI >> datatypes corresponding to C datatypes). The standard is clear that >> there are no corresponding C++ bindings. >> >>> Note that C99 complex is not a substitute because Microsoft does not >>> implement it and it has different semantics regarding numerical >>> stability. (Well, C99 semantics are specified and useful, std::complex >>> stability is not specified by any C++ standard and in practice, is not >>> implemented in a stable way.) This is not such a big deal for use with >>> collectives because user-defined MPI_Ops can be used, but only >>> predefined types can be used with one-sided operations, so presence of >>> complex datatypes (or lack thereof) is relevant to applications. >> >> The fact that Microsoft does not support C99 is lame. You can probably >> get away using std::complex as a stand-in for C99 _Complex (but then >> you're on your own), or move to a compiler that does (I believe the >> Intel compiler supports C99 on Windows). >> >> -Fab >> >

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Re: [Mpi-forum] C++ types inaccessible after #281
by Jed Brown 25 Jun '12

25 Jun '12

MPI::COMPLEX is not the same as MPI_C_COMPLEX (and the latter is not available on systems without C99). On Jun 25, 2012 8:21 PM, "Fab Tillier" <ftillier(a)microsoft.com> wrote: > Hi Jed, > > Maybe I'm not following you, but what predefined MPI datatype supports > std::complex today? My understanding is that there is no support for > std::complex in MPI today, and that ticket 281 does not change this at all. > > Thanks, > -Fab > > Jed Brown wrote on Mon, 25 Jun 2012 at 20:42:53 > > > I see that std::complex will not be accessible in a predefined type if > > #281 passes in its current form. Do you intend for there to be a > > supported/recommended way for a C++ caller to get a complex predefined > > (so that one-sided can be used) type? Note that C99 is not a subset of > > any C++ and C99 complex cannot be used portably from C++ (even with > > compiler suites that happen to support both). > > > On Jun 25, 2012 7:07 PM, "Fab Tillier" <ftillier(a)microsoft.com> wrote: > > Hi Jed, > > > > Jed Brown wrote on Mon, 25 Jun 2012 at 16:43:54 > > > >> Is it intended that #281 would make std::complex inaccessible? Should > >> there be a MPI_CXX_COMPLEX, MPI_CXX_DOUBLE_COMPLEX, > >> MPI_CXX_LONG_DOUBLE_COMPLEX, and (possibly) MPI_CXX_BOOL? > > > > I don't think ticket #281 does anything with respect to std::complex > > accessibility. The MPI standard defines the MPI_C_COMPLEX and family as > > mapping to the C99 _Complex type (see Table 3.2, Predefined MPI > > datatypes corresponding to C datatypes). The standard is clear that > > there are no corresponding C++ bindings. > > > >> Note that C99 complex is not a substitute because Microsoft does not > >> implement it and it has different semantics regarding numerical > >> stability. (Well, C99 semantics are specified and useful, std::complex > >> stability is not specified by any C++ standard and in practice, is not > >> implemented in a stable way.) This is not such a big deal for use with > >> collectives because user-defined MPI_Ops can be used, but only > >> predefined types can be used with one-sided operations, so presence of > >> complex datatypes (or lack thereof) is relevant to applications. > > > > The fact that Microsoft does not support C99 is lame. You can probably > > get away using std::complex as a stand-in for C99 _Complex (but then > > you're on your own), or move to a compiler that does (I believe the > > Intel compiler supports C99 on Windows). > > > > -Fab > > >

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Re: [Mpi-forum] C++ types inaccessible after #281
by Fab Tillier 25 Jun '12

25 Jun '12

Hi Jed, Maybe I'm not following you, but what predefined MPI datatype supports std::complex today? My understanding is that there is no support for std::complex in MPI today, and that ticket 281 does not change this at all. Thanks, -Fab Jed Brown wrote on Mon, 25 Jun 2012 at 20:42:53 > I see that std::complex will not be accessible in a predefined type if > #281 passes in its current form. Do you intend for there to be a > supported/recommended way for a C++ caller to get a complex predefined > (so that one-sided can be used) type? Note that C99 is not a subset of > any C++ and C99 complex cannot be used portably from C++ (even with > compiler suites that happen to support both). > On Jun 25, 2012 7:07 PM, "Fab Tillier" <ftillier(a)microsoft.com> wrote: > Hi Jed, > > Jed Brown wrote on Mon, 25 Jun 2012 at 16:43:54 > >> Is it intended that #281 would make std::complex inaccessible? Should >> there be a MPI_CXX_COMPLEX, MPI_CXX_DOUBLE_COMPLEX, >> MPI_CXX_LONG_DOUBLE_COMPLEX, and (possibly) MPI_CXX_BOOL? > > I don't think ticket #281 does anything with respect to std::complex > accessibility. The MPI standard defines the MPI_C_COMPLEX and family as > mapping to the C99 _Complex type (see Table 3.2, Predefined MPI > datatypes corresponding to C datatypes). The standard is clear that > there are no corresponding C++ bindings. > >> Note that C99 complex is not a substitute because Microsoft does not >> implement it and it has different semantics regarding numerical >> stability. (Well, C99 semantics are specified and useful, std::complex >> stability is not specified by any C++ standard and in practice, is not >> implemented in a stable way.) This is not such a big deal for use with >> collectives because user-defined MPI_Ops can be used, but only >> predefined types can be used with one-sided operations, so presence of >> complex datatypes (or lack thereof) is relevant to applications. > > The fact that Microsoft does not support C99 is lame. You can probably > get away using std::complex as a stand-in for C99 _Complex (but then > you're on your own), or move to a compiler that does (I believe the > Intel compiler supports C99 on Windows). > > -Fab >

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Re: [Mpi-forum] C++ types inaccessible after #281
by Jed Brown 25 Jun '12

25 Jun '12

I see that std::complex will not be accessible in a predefined type if #281 passes in its current form. Do you intend for there to be a supported/recommended way for a C++ caller to get a complex predefined (so that one-sided can be used) type? Note that C99 is not a subset of any C++ and C99 complex cannot be used portably from C++ (even with compiler suites that happen to support both). On Jun 25, 2012 7:07 PM, "Fab Tillier" <ftillier(a)microsoft.com> wrote: > Hi Jed, > > Jed Brown wrote on Mon, 25 Jun 2012 at 16:43:54 > > > Is it intended that #281 would make std::complex inaccessible? Should > > there be a MPI_CXX_COMPLEX, MPI_CXX_DOUBLE_COMPLEX, > > MPI_CXX_LONG_DOUBLE_COMPLEX, and (possibly) MPI_CXX_BOOL? > > I don't think ticket #281 does anything with respect to std::complex > accessibility. The MPI standard defines the MPI_C_COMPLEX and family as > mapping to the C99 _Complex type (see Table 3.2, Predefined MPI datatypes > corresponding to C datatypes). The standard is clear that there are no > corresponding C++ bindings. > > > Note that C99 complex is not a substitute because Microsoft does not > > implement it and it has different semantics regarding numerical > > stability. (Well, C99 semantics are specified and useful, std::complex > > stability is not specified by any C++ standard and in practice, is not > > implemented in a stable way.) This is not such a big deal for use with > > collectives because user-defined MPI_Ops can be used, but only > > predefined types can be used with one-sided operations, so presence of > > complex datatypes (or lack thereof) is relevant to applications. > > The fact that Microsoft does not support C99 is lame. You can probably > get away using std::complex as a stand-in for C99 _Complex (but then you're > on your own), or move to a compiler that does (I believe the Intel compiler > supports C99 on Windows). > > -Fab > >

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Re: [Mpi-forum] C++ types inaccessible after #281
by Fab Tillier 25 Jun '12

25 Jun '12

Hi Jed, Jed Brown wrote on Mon, 25 Jun 2012 at 16:43:54 > Is it intended that #281 would make std::complex inaccessible? Should > there be a MPI_CXX_COMPLEX, MPI_CXX_DOUBLE_COMPLEX, > MPI_CXX_LONG_DOUBLE_COMPLEX, and (possibly) MPI_CXX_BOOL? I don't think ticket #281 does anything with respect to std::complex accessibility. The MPI standard defines the MPI_C_COMPLEX and family as mapping to the C99 _Complex type (see Table 3.2, Predefined MPI datatypes corresponding to C datatypes). The standard is clear that there are no corresponding C++ bindings. > Note that C99 complex is not a substitute because Microsoft does not > implement it and it has different semantics regarding numerical > stability. (Well, C99 semantics are specified and useful, std::complex > stability is not specified by any C++ standard and in practice, is not > implemented in a stable way.) This is not such a big deal for use with > collectives because user-defined MPI_Ops can be used, but only > predefined types can be used with one-sided operations, so presence of > complex datatypes (or lack thereof) is relevant to applications. The fact that Microsoft does not support C99 is lame. You can probably get away using std::complex as a stand-in for C99 _Complex (but then you're on your own), or move to a compiler that does (I believe the Intel compiler supports C99 on Windows). -Fab

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C++ types inaccessible after #281
by Jed Brown 25 Jun '12

25 Jun '12

Is it intended that #281 would make std::complex inaccessible? Should there be a MPI_CXX_COMPLEX, MPI_CXX_DOUBLE_COMPLEX, MPI_CXX_LONG_DOUBLE_COMPLEX, and (possibly) MPI_CXX_BOOL? Note that C99 complex is not a substitute because Microsoft does not implement it and it has different semantics regarding numerical stability. (Well, C99 semantics are specified and useful, std::complex stability is not specified by any C++ standard and in practice, is not implemented in a stable way.) This is not such a big deal for use with collectives because user-defined MPI_Ops can be used, but only predefined types can be used with one-sided operations, so presence of complex datatypes (or lack thereof) is relevant to applications.

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Hotel for the July meeting
by Richard Graham 25 Jun '12

25 Jun '12

Just a reminder that today is the last day to get a room in the block of rooms reserved for this meeting. A block of rooms is reserved at the Residence Inn Chicago Downtown, River North at 410 N. Dearborn in Chicago, IL 60654. Rooms blocked at the rate of $155 for July 15-20. To reserve call central reservations at 866-905-5416 and reference the MPI Forum. Cut-off date June 25th. Rich

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