Ralph pinged Edgar and me about this off-list -- I speculated that that chunk of code could be replaced with:
OBJ_RELEASE(ompi_mpi_comm_parent); ompi_mpi_comm_parent = newcomm; ...but that was after only a quick look at the code. :-) There might well have been a good reason why it wasn't written that way in the first place. On Aug 25, 2010, at 1:25 PM, George Bosilca wrote: > In this particular case the compiler is both right and wrong. It is right to > complain, because as Paul pointed out, there is a free on a non-malloced > object (ompi_mpi_comm_null). However, this free is protected by the reference > count going to zero, and this should never happens in this particular piece > of code (hopefully!). > > What we really need here is one of the following: > 1) to simply decrease the reference count once, to signal that > ompi_comm_parent is not using the ompi_mpi_comm_null anymore. Unfortunately, > we don't have such a macro. > > 2) As, in this code, we handle only statically allocated objects remove the > OBJ_RELEASE from the dyn_init code, and their counterpart (OBJ_RETAIN) in the > comm_init.c:166. > > george. > > On Aug 25, 2010, at 12:05 , Paul H. Hargrove wrote: > >> Ralph, >> >> This is seen when compiling Open MPI. I suspect that gcc's analysis is >> seeing a free() call on a value it can prove did not come from malloc() (or >> equivalent). However, if as you say the value is always NULL, then this >> would be a false alarm. >> >> -Paul >> >> Ralph Castain wrote: >>> Hi Paul >>> >>> Much appreciate all your testing! >>> >>> Quick question here: is this on compile, or were you trying to run >>> something? >>> >>> We haven't seen this before, but I'm wondering if it is due to us failing >>> to initialize an object's fields. If so, then it might be we don't see it >>> because those fields usually default to zero (looks like NULL), but you >>> might see it if they don't on your system. >>> >>> Ralph >>> >>> On Aug 24, 2010, at 10:19 PM, Paul H. Hargrove wrote: >>> >>> >>>> With both recent RCs I get the following suspicious warnings from >>>> gcc-4.5.0 on Linux/ia64 >>>> >>>> 1.4.3rc1: >>>> >>>> ../../../../../ompi/mca/dpm/orte/dpm_orte.c:963:5: warning: attempt to >>>> free a non-heap object 'ompi_mpi_comm_null' >>>> ../../../../../ompi/mca/dpm/orte/dpm_orte.c:965:5: warning: attempt to >>>> free a non-heap object 'ompi_mpi_group_null' >>>> ../../../../../ompi/mca/dpm/orte/dpm_orte.c:967:5: warning: attempt to >>>> free a non-heap object 'ompi_mpi_errors_are_fatal' >>>> >>>> >>>> 1.5rc5: >>>> >>>> ../../../../../ompi/mca/dpm/orte/dpm_orte.c:990:5: warning: attempt to >>>> free a non-heap object 'ompi_mpi_comm_null' >>>> ../../../../../ompi/mca/dpm/orte/dpm_orte.c:992:5: warning: attempt to >>>> free a non-heap object 'ompi_mpi_group_null' >>>> ../../../../../ompi/mca/dpm/orte/dpm_orte.c:994:5: warning: attempt to >>>> free a non-heap object 'ompi_mpi_errors_are_fatal' >>>> >>>> -Paul >>>> >>>> -- >>>> Paul H. Hargrove phhargr...@lbl.gov >>>> Future Technologies Group >>>> HPC Research Department Tel: +1-510-495-2352 >>>> Lawrence Berkeley National Laboratory Fax: +1-510-486-6900 >>>> >>>> _______________________________________________ >>>> devel mailing list >>>> de...@open-mpi.org >>>> http://www.open-mpi.org/mailman/listinfo.cgi/devel >>>> >>> >>> >>> _______________________________________________ >>> devel mailing list >>> de...@open-mpi.org >>> http://www.open-mpi.org/mailman/listinfo.cgi/devel >>> >> >> -- >> Paul H. Hargrove phhargr...@lbl.gov >> Future Technologies Group >> HPC Research Department Tel: +1-510-495-2352 >> Lawrence Berkeley National Laboratory Fax: +1-510-486-6900 >> >> _______________________________________________ >> devel mailing list >> de...@open-mpi.org >> http://www.open-mpi.org/mailman/listinfo.cgi/devel > > > _______________________________________________ > devel mailing list > de...@open-mpi.org > http://www.open-mpi.org/mailman/listinfo.cgi/devel -- Jeff Squyres jsquy...@cisco.com For corporate legal information go to: http://www.cisco.com/web/about/doing_business/legal/cri/
