Hi, I have worked to reproduce the bug in a somewhat small example. On on any good MPI version, the output of the attached example is: Rank 1: Element # 33 : {40,106,105,204,208,200},8 Rank 1: Element # 34 : {61,105,106,201,208,205},8 Rank 1: Element # 35 : {40,105,107,200,212,209},8 Rank 1: Element # 36 : {62,107,105,210,212,202},8 Rank 1: Element # 37 : {40,108,106,213,216,204},8 Rank 1: Element # 38 : {42,110,85,223,227,108},8 On the mpich/master branch, since may 24, commit 60035bb7b9766db15041033959e4209f0ad936b, the output is: Rank 1: Element # 33 : {40,106,105,204,208,200},8 Rank 1: Element # 34 : {52,76,104,74,197,195},8 Rank 1: Element # 35 : {62,105,65,202,203,40},8 Rank 1: Element # 36 : {63,66,106,41,207,206},8 Rank 1: Element # 37 : {40,106,105,204,208,200},8 Rank 1: Element # 38 : {42,110,85,223,227,108},8 I hope you wil be able to work with my example to reproduce and solve this problem! Compile & run with: mpic++ -o bugmaster mpich_bug_indexed_type.cc mpirun -n 2 bugmaster Thanks a lot, Eric Le 2019-06-05 à 9:18 a.m., Eric Chamberland via discuss a écrit :

Hi,

I am in the early debugging stages of something that broke on may 24 on our test database with 17 tests against mpich/master branch.

It seems related to MPI I/O, since we have observed the bugs just after MPI I/O reads.

Everything is fine with other MPI libs, even older mpich.  This is only a mpich/master problem.

My early query: am I alone to have observed this?

Thanks,

Eric _______________________________________________ discuss mailing list     [email protected] To manage subscription options or unsubscribe: https://lists.mpich.org/mailman/listinfo/discuss