Hi Martin, My apologies for the lack of update on this topic. We did not include this patch because even with successful compilation, MPICH hcoll integration does not function correctly at runtime in our tests. Due to other priorities, we have not yet spent the time to fix the issue. Ken From: Audet, Martin via discuss <[email protected]> Date: Monday, June 23, 2025 at 10:04 AM To: [email protected] <[email protected]> Cc: Audet, Martin <[email protected]> Subject: [mpich-discuss] mpich 4.3.1 still have compilation problem when using --with-hcoll=/opt/mellanox/hcoll Hello, It seems that the silly compilation problem with hcoll_rte. c I had back in April with mpich 4. 3. 0 when using --with-hcoll=/opt/mellanox/hcoll configuration option is still present in 4. 3. 1, see: https: //lists. mpich. org/mailman/htdig/discuss/2025-April/006725. html ZjQcmQRYFpfptBannerStart This Message Is From an External Sender This message came from outside your organization. ZjQcmQRYFpfptBannerEnd Hello, It seems that the silly compilation problem with hcoll_rte.c I had back in April with mpich 4.3.0 when using --with-hcoll=/opt/mellanox/hcoll configuration option is still present in 4.3.1, see: https://urldefense.us/v3/__https://lists.mpich.org/mailman/htdig/discuss/202... <https://urldefense.us/v3/__https:/lists.mpich.org/mailman/htdig/discuss/2025-April/006725.html__;!!G_uCfscf7eWS!fvaja_SlDAvIzwz1hZZHt1QY74b9Va08hlq4gBLPtbxoN3xFpFmYKz6GBSA1PFywgC_JRwhwv3olRL2syH0Mhruza_g$> It seems that the following very simple patch I was told to try with 4.3.0 haven't been included in 4.3.1: --- src/mpid/common/hcoll/hcoll_rte.c 2025-04-16 12:54:24.847337975 -0400 +++ src/mpid/common/hcoll/hcoll_rte.c 2025-04-16 12:55:05.428164974 -0400 @@ -55,7 +55,7 @@ /* FIXME: The hcoll library needs to be updated to return * error codes. The progress function pointer right now * expects that the function returns void. */ - ret = hcoll_do_progress(&made_progress); + ret = hcoll_do_progress(-1, &made_progress); MPIR_Assert(ret == MPI_SUCCESS); } } So it look like this code path is not compiled very often by mpich developers or it's QA process. BTW applying the same patch fix the compilation problem, but: What does it mean for us users ? Should we still use this option ? BTW hcoll is a very cool mechanism for improving collective operations efficiency. Is this option obsolete ? Was it replaced by something else ? Thanks, Martin Audet