id	summary	reporter	owner	description	type	status	priority	milestone	component	resolution	keywords	cc
664	FW: Problem with MPI_Type_commit() and assert insegment_ops.c	"""Rajeev Thakur"" <thakur@…>"	rross	"

{{{




  _____

From: mpich2-dev-bounces@mcs.anl.gov
[mailto:mpich2-dev-bounces@mcs.anl.gov] On Behalf Of Joe Ratterman
Sent: Tuesday, June 09, 2009 3:14 PM
To: MPICH2 Dev
Subject: [mpich2-dev] Problem with MPI_Type_commit() and assert
insegment_ops.c


The specifics of this test come from an MPI excerciser that gathered
(using MPIR_Gather) a variety of types, including MPI_SHORT_INT.  The
way that gather is implemented, it created and then sent a struct
datatype of the tmp-data from the software tree and the local-data.  I
pulled out the important bits, and got this test-case.  It asserts on
PPC32 Linux 1.1 and BGP 1.1rc0, but runs fine on 1.0.7.  The
addresses/displacements are fake, but were originally based on the
actual values used inside MPIR_Gather.  It does the type-create on the
first two types just to show that it doesn't always fail.


Error message:


Creating  addr=[0x1,0x2]  types=[8c000003,4c00010d]  struct_displs=[1,2]
blocks=[256,256]  MPI_BOTTOM=(nil)
foo:25
Assertion failed in file segment_ops.c at line 994: *lengthp > 0
internal ABORT - process 0




Code


#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <mpi.h>

void foo(void *sendbuf,
         MPI_Datatype sendtype,
         void *recvbuf,
         MPI_Datatype recvtype)
{
  int blocks[2];
  MPI_Aint struct_displs[2];
  MPI_Datatype types[2], tmp_type;

  blocks[0] = 256;
  struct_displs[0] = (size_t)sendbuf;
  types[0] = sendtype;
  blocks[1] = 256;
  struct_displs[1] = (size_t)recvbuf;
  types[1] = MPI_BYTE;

  printf(""Creating  addr=[%p,%p]  types=[%x,%x]  struct_displs=[%x,%x]
blocks=[%d,%d]  MPI_BOTTOM=%p\n"",
         sendbuf, recvbuf, types[0], types[1], struct_displs[0],
struct_displs[1], blocks[0], blocks[1], MPI_BOTTOM);
  MPI_Type_create_struct(2, blocks, struct_displs, types, &tmp_type);
  printf(""%s:%d\n"", __func__, __LINE__);
  MPI_Type_commit(&tmp_type);
  printf(""%s:%d\n"", __func__, __LINE__);
  MPI_Type_free  (&tmp_type);
  puts(""Done"");
}


int main()
{
  MPI_Init(NULL, NULL);

  foo((void*)0x1,
      MPI_FLOAT_INT,
      (void*)0x2,
      MPI_BYTE);
  sleep(1);
  foo((void*)0x1,
      MPI_DOUBLE_INT,
      (void*)0x2,
      MPI_BYTE);
  sleep(1);
  foo((void*)0x1,
      MPI_SHORT_INT,
      (void*)0x2,
      MPI_BYTE);

  MPI_Finalize();
  return 0;
}




I don't know anything about how this might be fixed, but we are looking
into it as well.

Thanks,
Joe Ratterman
jratt@us.ibm.com
}}}"	bug	closed	major	mpich2-1.1.1	mpich2	fixed		jratt@…