Re: Refactoring backend fork+exec code

Hello Heikki,

01.12.2023 15:10, Heikki Linnakangas wrote:
> Attached is new version of these patches. For easier review, I made the new refactorings compared in a new commit
> 0003. I will squash that before pushing, but this makes it easier to see what changed.
>
> Barring any new feedback or issues, I will commit these.
>

Maybe you could look at issues with running `make check` under Valgrind
when server built with CPPFLAGS="-DUSE_VALGRIND -DEXEC_BACKEND":
# +++ regress check in src/test/regress +++
# initializing database system by copying initdb template
# postmaster failed, examine ".../src/test/regress/log/postmaster.log" for the reason
Bail out!make[1]: ***

...
2023-12-01 16:48:39.136 MSK postmaster[1307988] LOG:  listening on Unix socket "/tmp/pg_regress-pPFNk0/.s.PGSQL.55312"
==00:00:00:01.692 1259396== Syscall param write(buf) points to uninitialised byte(s)
==00:00:00:01.692 1259396==    at 0x5245A37: write (write.c:26)
==00:00:00:01.692 1259396==    by 0x51BBF6C: _IO_file_write@@GLIBC_2.2.5 (fileops.c:1180)
==00:00:00:01.692 1259396==    by 0x51BC84F: new_do_write (fileops.c:448)
==00:00:00:01.692 1259396==    by 0x51BC84F: _IO_new_file_xsputn (fileops.c:1254)
==00:00:00:01.692 1259396==    by 0x51BC84F: _IO_file_xsputn@@GLIBC_2.2.5 (fileops.c:1196)
==00:00:00:01.692 1259396==    by 0x51B1056: fwrite (iofwrite.c:39)
==00:00:00:01.692 1259396==    by 0x552E21: internal_forkexec (postmaster.c:4518)
==00:00:00:01.692 1259396==    by 0x5546A1: postmaster_forkexec (postmaster.c:4444)
==00:00:00:01.692 1259396==    by 0x55471C: StartChildProcess (postmaster.c:5275)
==00:00:00:01.692 1259396==    by 0x557B61: PostmasterMain (postmaster.c:1454)
==00:00:00:01.692 1259396==    by 0x472136: main (main.c:198)
==00:00:00:01.692 1259396==  Address 0x1ffeffdc11 is on thread 1's stack
==00:00:00:01.692 1259396==  in frame #4, created by internal_forkexec (postmaster.c:4482)
==00:00:00:01.692 1259396==

With memset(param, 0, sizeof(*param)); added at the beginning of
save_backend_variables(), server starts successfully, but then
`make check` fails with other Valgrind error.

Best regards,
Alexander