On Thu, Jul 14, 2022 at 11:16 AM shiy.f...@fujitsu.com <shiy.f...@fujitsu.com> wrote: > > On Tue, Jul 12, 2022 5:23 PM Masahiko Sawada <sawada.m...@gmail.com> wrote: > > > > On Tue, Jul 12, 2022 at 5:58 PM shiy.f...@fujitsu.com > > <shiy.f...@fujitsu.com> wrote: > > > > > > It happened when executing the following code because it tried to free a > > NULL > > > pointer (catchange_xip). > > > > > > /* be tidy */ > > > if (ondisk) > > > pfree(ondisk); > > > + if (catchange_xip) > > > + pfree(catchange_xip); > > > } > > > > > > It seems to be related to configure option. I could reproduce it when > > > using > > > `./configure --enable-debug`. > > > But I couldn't reproduce with `./configure --enable-debug CFLAGS="-Og - > > ggdb"`. > > > > Hmm, I could not reproduce this problem even if I use ./configure > > --enable-debug. And it's weird that we checked if catchange_xip is not > > null but we did pfree for it: > > > > #1 pfree (pointer=0x0) at mcxt.c:1177 > > #2 0x000000000078186b in SnapBuildSerialize (builder=0x1fd5e78, > > lsn=25719712) at snapbuild.c:1792 > > > > Is it reproducible in your environment? > > Thanks for your reply! Yes, it is reproducible. And I also reproduced it on > the > v4 patch you posted [1].
Thank you for testing! > > [1] > https://www.postgresql.org/message-id/CAD21AoAyNPrOFg%2BQGh%2B%3D4205TU0%3DyrE%2BQyMgzStkH85uBZXptQ%40mail.gmail.com > > > If so, could you test it again > > with the following changes? > > > > diff --git a/src/backend/replication/logical/snapbuild.c > > b/src/backend/replication/logical/snapbuild.c > > index d015c06ced..a6e76e3781 100644 > > --- a/src/backend/replication/logical/snapbuild.c > > +++ b/src/backend/replication/logical/snapbuild.c > > @@ -1788,7 +1788,7 @@ out: > > /* be tidy */ > > if (ondisk) > > pfree(ondisk); > > - if (catchange_xip) > > + if (catchange_xip != NULL) > > pfree(catchange_xip); > > } > > > > I tried this and could still reproduce the problem. Does the backtrace still show we attempt to pfree a null-pointer? > > Besides, I tried the suggestion from Amit [2], it could be fixed by checking > the value of catchange_xcnt instead of catchange_xip before pfree. Could you check if this problem occurred when we reached there via goto pass, i.e., did we call ReorderBufferGetCatalogChangesXacts() or not? Regards, -- Masahiko Sawada EDB: https://www.enterprisedb.com/
