[mpich-discuss] MPI_Gather error

[Jayesh Krishna]

Hi,
 The error usually occurs when you use the same buffer to send and receive data and don't use the MPI_IN_PLACE option (In your code pass MPI_IN_PLACE as the value of sendbuf in root.).
 You might (should) get the same error with the latest version of MPICH2 on Linux too.
 Let us know if it works for you.

Regards,
Jayesh
----- Original Message -----
From: Prashanth <prashanth.dumpuri at gmail.com>
To: mpich-discuss at mcs.anl.gov
Sent: Tue, 16 Nov 2010 11:26:36 -0600 (CST)
Subject: [mpich-discuss] MPI_Gather error

All,
   I have been using MPICH2 in linux and recently switched to Windows XP. My
code worked fine under Linux but in Windows I get the following error
message:

Fatal error in PMPI_Gather: Invalid buffer pointer, error stack:
PMPI_Gather(786): MPI_Gather(sbug=04785FF8, scount=1, MPI_INT,
rbuf=04785FF8, rcount=1, MPI_INT, root=0, MPI_COMM_WORLD) failed
PMPI_Gather(729): Buffers must not be aliased.

( here is line in the code where i get the above error:

MPI_Gather((void*)&recvcnts[rank],1,MPI_INT,(void*)recvcnts,1,MPI_INT,0,MPI_COMM_WORLD);

i have defined recvcnts to be an integer array )

Please note that the above line and code works fine in Linux. Any help on
this will be greatly appreciated.

Thanks
Prashanth