Re: [PATCH] O_CLOEXEC not honored on Windows - handle inheritance chain

On 12/12/2025 9:57 PM, Thomas Munro wrote:
> On Sat, Dec 13, 2025 at 3:44 PM Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us> wrote:
>> Thomas Munro <thomas(dot)munro(at)gmail(dot)com> writes:
>>> Hearing nothing, pushed.
>>
>> fairywren is unimpressed:
>>
>> ../pgsql/src/test/modules/test_cloexec/test_cloexec.c: In function 'run_parent_tests':
>> ../pgsql/src/test/modules/test_cloexec/test_cloexec.c:137:29: warning: unused variable 'space_pos' [-Wunused-variable]
>> 137 | char *space_pos;
>> | ^~~~~~~~~
>
> The CI MinGW task also shows this warning, but it doesn't use -Werror.
> The separate CompileWarnings task does, being its purpose, and it
> includes a MinGW cross-build step, but that uses configure, and this
> test is built only by meson. That wasn't a great idea... we knew we
> were only dealing with Windows but forgot about MinGW, so I'll go and
> write a patch to fix that aspect later today so we're covered for
> warnings. I'll also think about whether it's worth checking for MinGW
> warnings in both assert and non-assert builds (as we do for regular
> Linux gcc/clang), and I'd also like to try to catch warnings from MSVC
> and had an idea for how to do that... I might also try to think about
> meson-vs-configure cross checks...
>
>> What is the point of that first snprintf(cmdline, ...), when its
>> result is guaranteed to be overwritten just below?
>>
>> I'm also dubious about using MAX_PATH here; see the commentary
>> about MAXPGPATH in pg_config_manual.h. Also, what's the point of
>> using MAX_PATH when the result is going to be transferred into
>> cmdline (with a hardwired size of 1024)?
>
> Fair points, I'll wait and see if Bryan is free to write a patch on
> Monday (US), and otherwise write one myself.
Thomas,

A sanity check would be appreciated after the somewhat embarrassing
sloppy code.

I removed the useless snprintf() call that was using GetCommandLine().
That was left in place when I moved to GetModuleFileName(). Also,
removed the unused 'space_pos' variable and the unneeded scope block. I
decided to just use 1024 for the exe_path size since that is what
cmdline is set to use. I also removed some self-evident comments that
were leftover from my practice of writing comments and then coding.

Apologies for the loss of time.

Thanks,

--
Bryan Green
EDB: https://www.enterprisedb.com